├── .gitignore ├── 01-basic-websocket-server ├── .gitignore ├── README.md ├── build.gradle.kts ├── gradle │ └── wrapper │ │ ├── gradle-wrapper.jar │ │ └── gradle-wrapper.properties ├── gradlew ├── gradlew.bat ├── settings.gradle.kts └── src │ ├── main │ ├── kotlin │ │ └── com │ │ │ └── example │ │ │ └── websocket │ │ │ ├── WebsocketServerApplication.kt │ │ │ ├── config │ │ │ ├── RedisConfig.kt │ │ │ └── WebSocketConfig.kt │ │ │ ├── controller │ │ │ ├── NotificationController.kt │ │ │ └── WebsocketController.kt │ │ │ ├── model │ │ │ └── NewMessageRequest.kt │ │ │ └── service │ │ │ └── RedisService.kt │ └── resources │ │ └── application.yml │ └── test │ └── kotlin │ └── com │ └── example │ └── websocket │ └── WebsocketServerApplicationTests.kt ├── 02-scaling-websocket-server ├── .gitignore ├── README.md ├── backend-service │ ├── .gitignore │ ├── build.gradle.kts │ ├── settings.gradle.kts │ └── src │ │ ├── main │ │ ├── kotlin │ │ │ └── com │ │ │ │ └── example │ │ │ │ └── backend │ │ │ │ ├── BackendApplication.kt │ │ │ │ ├── config │ │ │ │ └── RedisStreamConfig.kt │ │ │ │ └── service │ │ │ │ ├── RedisStreamConsumer.kt │ │ │ │ └── RedisStreamProducer.kt │ │ └── resources │ │ │ └── application.yml │ │ └── test │ │ └── kotlin │ │ └── com │ │ └── example │ │ └── backend │ │ └── BackendApplicationTests.kt ├── build.gradle.kts ├── common-dto │ ├── .gitignore │ ├── build.gradle.kts │ ├── settings.gradle.kts │ └── src │ │ └── main │ │ ├── kotlin │ │ └── com │ │ │ └── example │ │ │ └── common │ │ │ └── model │ │ │ └── StreamDataEvent.kt │ │ └── resources │ │ └── application.yml ├── gradle │ └── wrapper │ │ ├── gradle-wrapper.jar │ │ └── gradle-wrapper.properties ├── gradlew ├── gradlew.bat ├── settings.gradle.kts └── websocket-server │ ├── .gitignore │ ├── build.gradle.kts │ ├── settings.gradle.kts │ └── src │ ├── main │ ├── kotlin │ │ └── com │ │ │ └── example │ │ │ └── websocket │ │ │ ├── WebsocketServerApplication.kt │ │ │ ├── config │ │ │ ├── RedisConfig.kt │ │ │ ├── RedisStreamConfig.kt │ │ │ └── WebSocketConfig.kt │ │ │ ├── controller │ │ │ ├── NotificationController.kt │ │ │ └── WebsocketController.kt │ │ │ ├── model │ │ │ ├── BroadcastEvent.kt │ │ │ └── NewMessageRequest.kt │ │ │ └── service │ │ │ ├── RedisBroadcastService.kt │ │ │ ├── RedisStreamConsumer.kt │ │ │ └── RedisStreamProducer.kt │ └── resources │ │ └── application.yml │ └── test │ └── kotlin │ └── com │ └── example │ └── websocket │ └── WebsocketServerApplicationTests.kt ├── LICENSE ├── README.md └── docs └── diagram.drawio /.gitignore: -------------------------------------------------------------------------------- 1 | .idea 2 | .vscode -------------------------------------------------------------------------------- /01-basic-websocket-server/.gitignore: -------------------------------------------------------------------------------- 1 | HELP.md 2 | .gradle 3 | build/ 4 | !gradle/wrapper/gradle-wrapper.jar 5 | !**/src/main/**/build/ 6 | !**/src/test/**/build/ 7 | 8 | ### STS ### 9 | .apt_generated 10 | .classpath 11 | .factorypath 12 | .project 13 | .settings 14 | .springBeans 15 | .sts4-cache 16 | bin/ 17 | !**/src/main/**/bin/ 18 | !**/src/test/**/bin/ 19 | 20 | ### IntelliJ IDEA ### 21 | .idea 22 | *.iws 23 | *.iml 24 | *.ipr 25 | out/ 26 | !**/src/main/**/out/ 27 | !**/src/test/**/out/ 28 | 29 | ### NetBeans ### 30 | /nbproject/private/ 31 | /nbbuild/ 32 | /dist/ 33 | /nbdist/ 34 | /.nb-gradle/ 35 | 36 | ### VS Code ### 37 | .vscode/ 38 | -------------------------------------------------------------------------------- /01-basic-websocket-server/README.md: -------------------------------------------------------------------------------- 1 | # Building a Websocket Server 2 | 3 | This section covers how to build a simple websocket server using Spring Boot and Redis Pub/Sub. In a microservice architecture, 4 | the websocket server is the only microservice that establishes websocket connections with the web application (Frontend). It 5 | also acts as a middleware (or proxy) for real-time communications between the web application (Frontend) and other microservices 6 | (Backend). For more information, check out [this article](https://medium.com/@kbryan1008/building-a-websocket-server-in-a-microservice-architecture-50c6c6432e2b). 7 | 8 | ## Usage 9 | 10 | 1. Start the Redis Server 11 | 12 | ```bash 13 | docker run --name redis -p 6379:6379 -d redis:6.2.6 14 | ``` 15 | 16 | 2. Start the Websocket Server 17 | 18 | ```bash 19 | ./gradlew bootrun 20 | ``` 21 | 22 | ## Useful Commands 23 | 24 | ```bash 25 | # POST Request 26 | curl -X POST -d '{"topic": "/topic/toast", "message": "testing API endpoint" }' -H "Content-Type: application/json" localhost:8080/api/notification 27 | 28 | # Redis CLI 29 | docker exec -it redis redis-cli 30 | PUBSUB CHANNELS 31 | PUBLISH GREETING_CHANNEL_INBOUND "\"Test\"" 32 | SUBSCRIBE GREETING_CHANNEL_OUTBOUND 33 | ``` 34 | -------------------------------------------------------------------------------- /01-basic-websocket-server/build.gradle.kts: -------------------------------------------------------------------------------- 1 | import org.jetbrains.kotlin.gradle.tasks.KotlinCompile 2 | 3 | plugins { 4 | id("org.springframework.boot") version "2.5.6" 5 | id("io.spring.dependency-management") version "1.0.11.RELEASE" 6 | kotlin("jvm") version "1.5.31" 7 | kotlin("plugin.spring") version "1.5.31" 8 | } 9 | 10 | group = "com.example" 11 | version = "0.0.1-SNAPSHOT" 12 | java.sourceCompatibility = JavaVersion.VERSION_11 13 | 14 | repositories { 15 | mavenCentral() 16 | } 17 | 18 | dependencies { 19 | // Spring Boot 20 | implementation("org.springframework.boot:spring-boot-starter-actuator") 21 | implementation("org.springframework.boot:spring-boot-starter-webflux") 22 | implementation("org.springframework.boot:spring-boot-starter-data-redis-reactive") 23 | implementation("org.springframework.boot:spring-boot-starter-websocket") 24 | 25 | // Kotlin 26 | implementation("com.fasterxml.jackson.module:jackson-module-kotlin") 27 | implementation("org.jetbrains.kotlin:kotlin-reflect") 28 | implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8") 29 | 30 | // Testing 31 | testImplementation("org.springframework.boot:spring-boot-starter-test") 32 | testImplementation("io.projectreactor:reactor-test") 33 | } 34 | 35 | tasks.withType { 36 | kotlinOptions { 37 | freeCompilerArgs = listOf("-Xjsr305=strict") 38 | jvmTarget = "11" 39 | } 40 | } 41 | 42 | tasks.withType { 43 | useJUnitPlatform() 44 | } 45 | -------------------------------------------------------------------------------- /01-basic-websocket-server/gradle/wrapper/gradle-wrapper.jar: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/bkjam/websocket-microservice/92f437b892945a4285ef25fc704f514d14488eb5/01-basic-websocket-server/gradle/wrapper/gradle-wrapper.jar -------------------------------------------------------------------------------- /01-basic-websocket-server/gradle/wrapper/gradle-wrapper.properties: -------------------------------------------------------------------------------- 1 | distributionBase=GRADLE_USER_HOME 2 | distributionPath=wrapper/dists 3 | distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.1-bin.zip 4 | zipStoreBase=GRADLE_USER_HOME 5 | zipStorePath=wrapper/dists 6 | -------------------------------------------------------------------------------- /01-basic-websocket-server/gradlew: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | # 4 | # Copyright © 2015-2021 the original authors. 5 | # 6 | # Licensed under the Apache License, Version 2.0 (the "License"); 7 | # you may not use this file except in compliance with the License. 8 | # You may obtain a copy of the License at 9 | # 10 | # https://www.apache.org/licenses/LICENSE-2.0 11 | # 12 | # Unless required by applicable law or agreed to in writing, software 13 | # distributed under the License is distributed on an "AS IS" BASIS, 14 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 | # See the License for the specific language governing permissions and 16 | # limitations under the License. 17 | # 18 | 19 | ############################################################################## 20 | # 21 | # Gradle start up script for POSIX generated by Gradle. 22 | # 23 | # Important for running: 24 | # 25 | # (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is 26 | # noncompliant, but you have some other compliant shell such as ksh or 27 | # bash, then to run this script, type that shell name before the whole 28 | # command line, like: 29 | # 30 | # ksh Gradle 31 | # 32 | # Busybox and similar reduced shells will NOT work, because this script 33 | # requires all of these POSIX shell features: 34 | # * functions; 35 | # * expansions «$var», «${var}», «${var:-default}», «${var+SET}», 36 | # «${var#prefix}», «${var%suffix}», and «$( cmd )»; 37 | # * compound commands having a testable exit status, especially «case»; 38 | # * various built-in commands including «command», «set», and «ulimit». 39 | # 40 | # Important for patching: 41 | # 42 | # (2) This script targets any POSIX shell, so it avoids extensions provided 43 | # by Bash, Ksh, etc; in particular arrays are avoided. 44 | # 45 | # The "traditional" practice of packing multiple parameters into a 46 | # space-separated string is a well documented source of bugs and security 47 | # problems, so this is (mostly) avoided, by progressively accumulating 48 | # options in "$@", and eventually passing that to Java. 49 | # 50 | # Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS, 51 | # and GRADLE_OPTS) rely on word-splitting, this is performed explicitly; 52 | # see the in-line comments for details. 53 | # 54 | # There are tweaks for specific operating systems such as AIX, CygWin, 55 | # Darwin, MinGW, and NonStop. 56 | # 57 | # (3) This script is generated from the Groovy template 58 | # https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt 59 | # within the Gradle project. 60 | # 61 | # You can find Gradle at https://github.com/gradle/gradle/. 62 | # 63 | ############################################################################## 64 | 65 | # Attempt to set APP_HOME 66 | 67 | # Resolve links: $0 may be a link 68 | app_path=$0 69 | 70 | # Need this for daisy-chained symlinks. 71 | while 72 | APP_HOME=${app_path%"${app_path##*/}"} # leaves a trailing /; empty if no leading path 73 | [ -h "$app_path" ] 74 | do 75 | ls=$( ls -ld "$app_path" ) 76 | link=${ls#*' -> '} 77 | case $link in #( 78 | /*) app_path=$link ;; #( 79 | *) app_path=$APP_HOME$link ;; 80 | esac 81 | done 82 | 83 | APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit 84 | 85 | APP_NAME="Gradle" 86 | APP_BASE_NAME=${0##*/} 87 | 88 | # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. 89 | DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"' 90 | 91 | # Use the maximum available, or set MAX_FD != -1 to use that value. 92 | MAX_FD=maximum 93 | 94 | warn () { 95 | echo "$*" 96 | } >&2 97 | 98 | die () { 99 | echo 100 | echo "$*" 101 | echo 102 | exit 1 103 | } >&2 104 | 105 | # OS specific support (must be 'true' or 'false'). 106 | cygwin=false 107 | msys=false 108 | darwin=false 109 | nonstop=false 110 | case "$( uname )" in #( 111 | CYGWIN* ) cygwin=true ;; #( 112 | Darwin* ) darwin=true ;; #( 113 | MSYS* | MINGW* ) msys=true ;; #( 114 | NONSTOP* ) nonstop=true ;; 115 | esac 116 | 117 | CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar 118 | 119 | 120 | # Determine the Java command to use to start the JVM. 121 | if [ -n "$JAVA_HOME" ] ; then 122 | if [ -x "$JAVA_HOME/jre/sh/java" ] ; then 123 | # IBM's JDK on AIX uses strange locations for the executables 124 | JAVACMD=$JAVA_HOME/jre/sh/java 125 | else 126 | JAVACMD=$JAVA_HOME/bin/java 127 | fi 128 | if [ ! -x "$JAVACMD" ] ; then 129 | die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME 130 | 131 | Please set the JAVA_HOME variable in your environment to match the 132 | location of your Java installation." 133 | fi 134 | else 135 | JAVACMD=java 136 | which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 137 | 138 | Please set the JAVA_HOME variable in your environment to match the 139 | location of your Java installation." 140 | fi 141 | 142 | # Increase the maximum file descriptors if we can. 143 | if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then 144 | case $MAX_FD in #( 145 | max*) 146 | MAX_FD=$( ulimit -H -n ) || 147 | warn "Could not query maximum file descriptor limit" 148 | esac 149 | case $MAX_FD in #( 150 | '' | soft) :;; #( 151 | *) 152 | ulimit -n "$MAX_FD" || 153 | warn "Could not set maximum file descriptor limit to $MAX_FD" 154 | esac 155 | fi 156 | 157 | # Collect all arguments for the java command, stacking in reverse order: 158 | # * args from the command line 159 | # * the main class name 160 | # * -classpath 161 | # * -D...appname settings 162 | # * --module-path (only if needed) 163 | # * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables. 164 | 165 | # For Cygwin or MSYS, switch paths to Windows format before running java 166 | if "$cygwin" || "$msys" ; then 167 | APP_HOME=$( cygpath --path --mixed "$APP_HOME" ) 168 | CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" ) 169 | 170 | JAVACMD=$( cygpath --unix "$JAVACMD" ) 171 | 172 | # Now convert the arguments - kludge to limit ourselves to /bin/sh 173 | for arg do 174 | if 175 | case $arg in #( 176 | -*) false ;; # don't mess with options #( 177 | /?*) t=${arg#/} t=/${t%%/*} # looks like a POSIX filepath 178 | [ -e "$t" ] ;; #( 179 | *) false ;; 180 | esac 181 | then 182 | arg=$( cygpath --path --ignore --mixed "$arg" ) 183 | fi 184 | # Roll the args list around exactly as many times as the number of 185 | # args, so each arg winds up back in the position where it started, but 186 | # possibly modified. 187 | # 188 | # NB: a `for` loop captures its iteration list before it begins, so 189 | # changing the positional parameters here affects neither the number of 190 | # iterations, nor the values presented in `arg`. 191 | shift # remove old arg 192 | set -- "$@" "$arg" # push replacement arg 193 | done 194 | fi 195 | 196 | # Collect all arguments for the java command; 197 | # * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of 198 | # shell script including quotes and variable substitutions, so put them in 199 | # double quotes to make sure that they get re-expanded; and 200 | # * put everything else in single quotes, so that it's not re-expanded. 201 | 202 | set -- \ 203 | "-Dorg.gradle.appname=$APP_BASE_NAME" \ 204 | -classpath "$CLASSPATH" \ 205 | org.gradle.wrapper.GradleWrapperMain \ 206 | "$@" 207 | 208 | # Use "xargs" to parse quoted args. 209 | # 210 | # With -n1 it outputs one arg per line, with the quotes and backslashes removed. 211 | # 212 | # In Bash we could simply go: 213 | # 214 | # readarray ARGS < <( xargs -n1 <<<"$var" ) && 215 | # set -- "${ARGS[@]}" "$@" 216 | # 217 | # but POSIX shell has neither arrays nor command substitution, so instead we 218 | # post-process each arg (as a line of input to sed) to backslash-escape any 219 | # character that might be a shell metacharacter, then use eval to reverse 220 | # that process (while maintaining the separation between arguments), and wrap 221 | # the whole thing up as a single "set" statement. 222 | # 223 | # This will of course break if any of these variables contains a newline or 224 | # an unmatched quote. 225 | # 226 | 227 | eval "set -- $( 228 | printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" | 229 | xargs -n1 | 230 | sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' | 231 | tr '\n' ' ' 232 | )" '"$@"' 233 | 234 | exec "$JAVACMD" "$@" 235 | -------------------------------------------------------------------------------- /01-basic-websocket-server/gradlew.bat: -------------------------------------------------------------------------------- 1 | @rem 2 | @rem Copyright 2015 the original author or authors. 3 | @rem 4 | @rem Licensed under the Apache License, Version 2.0 (the "License"); 5 | @rem you may not use this file except in compliance with the License. 6 | @rem You may obtain a copy of the License at 7 | @rem 8 | @rem https://www.apache.org/licenses/LICENSE-2.0 9 | @rem 10 | @rem Unless required by applicable law or agreed to in writing, software 11 | @rem distributed under the License is distributed on an "AS IS" BASIS, 12 | @rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 | @rem See the License for the specific language governing permissions and 14 | @rem limitations under the License. 15 | @rem 16 | 17 | @if "%DEBUG%" == "" @echo off 18 | @rem ########################################################################## 19 | @rem 20 | @rem Gradle startup script for Windows 21 | @rem 22 | @rem ########################################################################## 23 | 24 | @rem Set local scope for the variables with windows NT shell 25 | if "%OS%"=="Windows_NT" setlocal 26 | 27 | set DIRNAME=%~dp0 28 | if "%DIRNAME%" == "" set DIRNAME=. 29 | set APP_BASE_NAME=%~n0 30 | set APP_HOME=%DIRNAME% 31 | 32 | @rem Resolve any "." and ".." in APP_HOME to make it shorter. 33 | for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi 34 | 35 | @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. 36 | set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m" 37 | 38 | @rem Find java.exe 39 | if defined JAVA_HOME goto findJavaFromJavaHome 40 | 41 | set JAVA_EXE=java.exe 42 | %JAVA_EXE% -version >NUL 2>&1 43 | if "%ERRORLEVEL%" == "0" goto execute 44 | 45 | echo. 46 | echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 47 | echo. 48 | echo Please set the JAVA_HOME variable in your environment to match the 49 | echo location of your Java installation. 50 | 51 | goto fail 52 | 53 | :findJavaFromJavaHome 54 | set JAVA_HOME=%JAVA_HOME:"=% 55 | set JAVA_EXE=%JAVA_HOME%/bin/java.exe 56 | 57 | if exist "%JAVA_EXE%" goto execute 58 | 59 | echo. 60 | echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 61 | echo. 62 | echo Please set the JAVA_HOME variable in your environment to match the 63 | echo location of your Java installation. 64 | 65 | goto fail 66 | 67 | :execute 68 | @rem Setup the command line 69 | 70 | set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar 71 | 72 | 73 | @rem Execute Gradle 74 | "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %* 75 | 76 | :end 77 | @rem End local scope for the variables with windows NT shell 78 | if "%ERRORLEVEL%"=="0" goto mainEnd 79 | 80 | :fail 81 | rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of 82 | rem the _cmd.exe /c_ return code! 83 | if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1 84 | exit /b 1 85 | 86 | :mainEnd 87 | if "%OS%"=="Windows_NT" endlocal 88 | 89 | :omega 90 | -------------------------------------------------------------------------------- /01-basic-websocket-server/settings.gradle.kts: -------------------------------------------------------------------------------- 1 | rootProject.name = "websocker-server" 2 | -------------------------------------------------------------------------------- /01-basic-websocket-server/src/main/kotlin/com/example/websocket/WebsocketServerApplication.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket 2 | 3 | import org.springframework.boot.autoconfigure.SpringBootApplication 4 | import org.springframework.boot.runApplication 5 | 6 | @SpringBootApplication 7 | class WebsocketServerApplication 8 | 9 | fun main(args: Array) { 10 | runApplication(*args) 11 | } 12 | -------------------------------------------------------------------------------- /01-basic-websocket-server/src/main/kotlin/com/example/websocket/config/RedisConfig.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.config 2 | 3 | import org.springframework.context.annotation.Bean 4 | import org.springframework.context.annotation.Configuration 5 | import org.springframework.data.redis.connection.ReactiveKeyCommands 6 | import org.springframework.data.redis.connection.ReactiveRedisConnectionFactory 7 | import org.springframework.data.redis.connection.ReactiveStringCommands 8 | import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory 9 | import org.springframework.data.redis.core.ReactiveRedisTemplate 10 | import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer 11 | import org.springframework.data.redis.serializer.RedisSerializationContext 12 | import org.springframework.data.redis.serializer.StringRedisSerializer 13 | 14 | @Configuration 15 | class RedisConfig { 16 | @Bean 17 | fun reactiveRedisTemplate(factory: LettuceConnectionFactory): ReactiveRedisTemplate { 18 | val serializer = Jackson2JsonRedisSerializer(String::class.java) 19 | val builder = RedisSerializationContext.newSerializationContext(StringRedisSerializer()) 20 | val context = builder.value(serializer).build() 21 | return ReactiveRedisTemplate(factory, context) 22 | } 23 | 24 | @Bean 25 | fun keyCommands(reactiveRedisConnectionFactory: ReactiveRedisConnectionFactory): ReactiveKeyCommands { 26 | return reactiveRedisConnectionFactory.reactiveConnection.keyCommands() 27 | } 28 | 29 | @Bean 30 | fun stringCommands(reactiveRedisConnectionFactory: ReactiveRedisConnectionFactory): ReactiveStringCommands { 31 | return reactiveRedisConnectionFactory.reactiveConnection.stringCommands() 32 | } 33 | } 34 | -------------------------------------------------------------------------------- /01-basic-websocket-server/src/main/kotlin/com/example/websocket/config/WebSocketConfig.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.config 2 | 3 | import org.springframework.context.annotation.Configuration 4 | import org.springframework.messaging.simp.config.MessageBrokerRegistry 5 | import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker 6 | import org.springframework.web.socket.config.annotation.StompEndpointRegistry 7 | import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer 8 | 9 | @Configuration 10 | @EnableWebSocketMessageBroker 11 | class WebSocketConfig: WebSocketMessageBrokerConfigurer { 12 | override fun registerStompEndpoints(registry: StompEndpointRegistry) { 13 | registry.addEndpoint("/stomp").setAllowedOrigins("*") 14 | } 15 | 16 | override fun configureMessageBroker(registry: MessageBrokerRegistry) { 17 | registry.enableSimpleBroker("/topic") 18 | registry.setApplicationDestinationPrefixes("/app") 19 | } 20 | } 21 | -------------------------------------------------------------------------------- /01-basic-websocket-server/src/main/kotlin/com/example/websocket/controller/NotificationController.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.controller 2 | 3 | import com.example.websocket.model.NewMessageRequest 4 | import org.springframework.messaging.simp.SimpMessagingTemplate 5 | import org.springframework.web.bind.annotation.* 6 | 7 | @RestController 8 | @RequestMapping("/api/notification") 9 | class NotificationController(private val template: SimpMessagingTemplate) { 10 | @PostMapping 11 | fun newMessage(@RequestBody request: NewMessageRequest) { 12 | template.convertAndSend(request.topic, request.message) 13 | } 14 | } 15 | -------------------------------------------------------------------------------- /01-basic-websocket-server/src/main/kotlin/com/example/websocket/controller/WebsocketController.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.controller 2 | 3 | import com.example.websocket.service.RedisService 4 | import org.springframework.messaging.handler.annotation.MessageMapping 5 | import org.springframework.messaging.handler.annotation.Payload 6 | import org.springframework.stereotype.Controller 7 | 8 | @Controller 9 | class WebsocketController(private val redisService: RedisService) { 10 | @MessageMapping("/greet") 11 | fun greetMessage(@Payload message: String) { 12 | redisService.publish("GREETING_CHANNEL_OUTBOUND", message) 13 | } 14 | } 15 | -------------------------------------------------------------------------------- /01-basic-websocket-server/src/main/kotlin/com/example/websocket/model/NewMessageRequest.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.model 2 | 3 | data class NewMessageRequest( 4 | val topic: String, 5 | val message: String 6 | ) 7 | -------------------------------------------------------------------------------- /01-basic-websocket-server/src/main/kotlin/com/example/websocket/service/RedisService.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.service 2 | 3 | import org.springframework.data.redis.connection.ReactiveSubscription 4 | import org.springframework.data.redis.core.ReactiveRedisTemplate 5 | import org.springframework.data.redis.listener.ChannelTopic 6 | import org.springframework.messaging.simp.SimpMessagingTemplate 7 | import org.springframework.stereotype.Service 8 | import javax.annotation.PostConstruct 9 | 10 | @Service 11 | class RedisService( 12 | private val reactiveRedisTemplate: ReactiveRedisTemplate, 13 | private val websocketTemplate: SimpMessagingTemplate 14 | ) { 15 | fun publish(topic: String, message: String) { 16 | reactiveRedisTemplate.convertAndSend(topic, message).subscribe() 17 | } 18 | 19 | fun subscribe(channelTopic: String, destination: String) { 20 | reactiveRedisTemplate.listenTo(ChannelTopic.of(channelTopic)) 21 | .map(ReactiveSubscription.Message::getMessage) 22 | .subscribe { message -> 23 | websocketTemplate.convertAndSend(destination, message) 24 | } 25 | } 26 | 27 | @PostConstruct 28 | fun subscribe() { 29 | subscribe("GREETING_CHANNEL_INBOUND", "/topic/greetings") 30 | } 31 | } 32 | -------------------------------------------------------------------------------- /01-basic-websocket-server/src/main/resources/application.yml: -------------------------------------------------------------------------------- 1 | ############################################################################################### 2 | # Server Configuration 3 | ############################################################################################### 4 | 5 | server.port: 8080 6 | spring.application.name: websocket-server 7 | 8 | logging.level: 9 | root: INFO 10 | org.springframework.web: INFO 11 | org.springframework.web.HttpLogging: INFO 12 | com.example.websocket: DEBUG 13 | 14 | spring.redis: 15 | host: localhost # Redis Server Host 16 | port: 6379 # Redis Server Port 17 | ssl: false # Enable SSL support 18 | database: 0 # database index -------------------------------------------------------------------------------- /01-basic-websocket-server/src/test/kotlin/com/example/websocket/WebsocketServerApplicationTests.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket 2 | 3 | import org.junit.jupiter.api.Test 4 | import org.springframework.boot.test.context.SpringBootTest 5 | 6 | @SpringBootTest 7 | class WebsocketServerApplicationTests { 8 | 9 | @Test 10 | fun contextLoads() { 11 | } 12 | 13 | } 14 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/.gitignore: -------------------------------------------------------------------------------- 1 | HELP.md 2 | .gradle 3 | build/ 4 | !gradle/wrapper/gradle-wrapper.jar 5 | !**/src/main/**/build/ 6 | !**/src/test/**/build/ 7 | 8 | ### STS ### 9 | .apt_generated 10 | .classpath 11 | .factorypath 12 | .project 13 | .settings 14 | .springBeans 15 | .sts4-cache 16 | bin/ 17 | !**/src/main/**/bin/ 18 | !**/src/test/**/bin/ 19 | 20 | ### IntelliJ IDEA ### 21 | .idea 22 | *.iws 23 | *.iml 24 | *.ipr 25 | out/ 26 | !**/src/main/**/out/ 27 | !**/src/test/**/out/ 28 | 29 | ### NetBeans ### 30 | /nbproject/private/ 31 | /nbbuild/ 32 | /dist/ 33 | /nbdist/ 34 | /.nb-gradle/ 35 | 36 | ### VS Code ### 37 | .vscode/ 38 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/README.md: -------------------------------------------------------------------------------- 1 | # Horizontal Scaling the Websocket Server 2 | 3 | This section covers how to scale the websocket server and resolve the message loss issue using publish-subscribe messaging 4 | pattern. For more information, check out [this article](https://betterprogramming.pub/implement-a-scalable-websocket-server-with-spring-boot-redis-pub-sub-and-redis-streams-b6b8cc08767f). 5 | 6 | ## Usage 7 | 8 | 1. Start the Redis Server 9 | 10 | ```bash 11 | # Start the Redis Server 12 | docker run --name redis -p 6379:6379 -d redis:6.2.6 13 | 14 | # Create Consumer Group for the Event Stream that we are testing 15 | docker exec redis redis-cli XGROUP CREATE TEST_EVENT_TO_BACKEND CONSUMER_GROUP $ MKSTREAM 16 | ``` 17 | 18 | 2. Start up 2 or more Websocket Server instances 19 | 20 | ```bash 21 | ./gradlew websocket-server:bootrun -Pargs=--server.port=8080,--spring.application.name=websocket-server-A 22 | ./gradlew websocket-server:bootrun -Pargs=--server.port=8181,--spring.application.name=websocket-server-B 23 | ``` 24 | 25 | 3. Start up 2 or more backend instances 26 | 27 | ```bash 28 | ./gradlew backend-service:bootrun -Pargs=--server.port=18080,--spring.application.name=backend-A 29 | ./gradlew backend-service:bootrun -Pargs=--server.port=28080,--spring.application.name=backend-B 30 | ... 31 | ``` 32 | 33 | 4. Verify Redis Streams 34 | 35 | ```bash 36 | docker exec -it redis /bin/bash 37 | redis-cli 38 | xrange TEST_EVENT_TO_BACKEND - + 39 | xrange TEST_EVENT_TO_WEBSOCKET_SERVER - + 40 | ``` 41 | 42 | 5. Verify that only a single backend service received the message from websocket server (check the logs) 43 | 44 | 45 | ## Notable Issues 46 | 47 | 1. Redis NOGROUP error. You might hit the following issue where the consumer group is not created. To resolve, create the 48 | consumer group using the redis command: `XGROUP CREATE my_stream my_group $ MKSTREAM` 49 | 50 | ```bash 51 | org.springframework.data.redis.RedisSystemException: Error in execution; nested exception is io.lettuce.core.RedisCommandExecutionException: NOGROUP No such key 'TEST_EVENT_TO_BACKEND' or consumer group 'MY-GROUP' in XREADGROUP with GROUP option 52 | ``` 53 | 54 | 2. Deserializing _class issue. [https://github.com/spring-projects/spring-data-redis/issues/2251](https://github.com/spring-projects/spring-data-redis/issues/2251) 55 | 56 | ## Useful Commands 57 | 58 | ```bash 59 | # Redis Stream Commands 60 | xadd my_stream * key value key value ... 61 | xrange my_stream - + # Show stream from beginning to end 62 | XGROUP CREATE my_stream mygroup $ 63 | XINFO GROUPS 64 | ``` 65 | 66 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/.gitignore: -------------------------------------------------------------------------------- 1 | build -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/build.gradle.kts: -------------------------------------------------------------------------------- 1 | import org.jetbrains.kotlin.gradle.tasks.KotlinCompile 2 | 3 | plugins { 4 | id("org.springframework.boot") version "2.5.6" 5 | id("io.spring.dependency-management") version "1.0.11.RELEASE" 6 | kotlin("jvm") version "1.5.31" 7 | kotlin("plugin.spring") version "1.5.31" 8 | } 9 | 10 | group = "com.example" 11 | version = "0.0.1-SNAPSHOT" 12 | java.sourceCompatibility = JavaVersion.VERSION_11 13 | 14 | repositories { 15 | mavenCentral() 16 | } 17 | 18 | dependencies { 19 | // Dto 20 | implementation(project(":common-dto")) 21 | 22 | // Spring Boot 23 | implementation("org.springframework.boot:spring-boot-starter-actuator") 24 | implementation("org.springframework.boot:spring-boot-starter-webflux") 25 | implementation("org.springframework.boot:spring-boot-starter-data-redis-reactive") 26 | 27 | // Kotlin 28 | implementation("com.fasterxml.jackson.module:jackson-module-kotlin") 29 | implementation("org.jetbrains.kotlin:kotlin-reflect") 30 | implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8") 31 | 32 | // Testing 33 | testImplementation("org.springframework.boot:spring-boot-starter-test") 34 | testImplementation("io.projectreactor:reactor-test") 35 | } 36 | 37 | tasks.bootRun { 38 | if (project.hasProperty("args")) { 39 | args(project.properties["args"].toString().split(",")) 40 | } 41 | } 42 | 43 | tasks.withType { 44 | kotlinOptions { 45 | freeCompilerArgs = listOf("-Xjsr305=strict") 46 | jvmTarget = "11" 47 | } 48 | } 49 | 50 | tasks.withType { 51 | useJUnitPlatform() 52 | } 53 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/settings.gradle.kts: -------------------------------------------------------------------------------- 1 | rootProject.name = "backend-service" 2 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/src/main/kotlin/com/example/backend/BackendApplication.kt: -------------------------------------------------------------------------------- 1 | package com.example.backend 2 | 3 | import org.springframework.boot.autoconfigure.SpringBootApplication 4 | import org.springframework.boot.runApplication 5 | import org.springframework.scheduling.annotation.EnableScheduling 6 | 7 | @EnableScheduling 8 | @SpringBootApplication 9 | class BackendApplication 10 | 11 | fun main(args: Array) { 12 | runApplication(*args) 13 | } 14 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/src/main/kotlin/com/example/backend/config/RedisStreamConfig.kt: -------------------------------------------------------------------------------- 1 | package com.example.backend.config 2 | 3 | import com.example.common.model.StreamDataEvent 4 | import org.springframework.beans.factory.annotation.Value 5 | import org.springframework.context.annotation.Bean 6 | import org.springframework.context.annotation.Configuration 7 | import org.springframework.data.redis.connection.RedisConnectionFactory 8 | import org.springframework.data.redis.connection.stream.Consumer 9 | import org.springframework.data.redis.connection.stream.ObjectRecord 10 | import org.springframework.data.redis.connection.stream.ReadOffset 11 | import org.springframework.data.redis.connection.stream.StreamOffset 12 | import org.springframework.data.redis.stream.StreamListener 13 | import org.springframework.data.redis.stream.StreamMessageListenerContainer 14 | import org.springframework.data.redis.stream.Subscription 15 | import java.time.Duration 16 | 17 | @Configuration 18 | class RedisStreamConfig( 19 | private val streamListener: StreamListener>, 20 | @Value("\${spring.application.name}") private val applicationName: String 21 | ) { 22 | @Bean 23 | fun subscription(redisConnectionFactory: RedisConnectionFactory): Subscription { 24 | val options = StreamMessageListenerContainer 25 | .StreamMessageListenerContainerOptions 26 | .builder() 27 | .pollTimeout(Duration.ofSeconds(1)) 28 | .targetType(StreamDataEvent::class.java) 29 | .build() 30 | val listenerContainer = StreamMessageListenerContainer.create(redisConnectionFactory, options) 31 | val subscription = listenerContainer.receiveAutoAck( 32 | Consumer.from("CONSUMER_GROUP", applicationName), 33 | StreamOffset.create("TEST_EVENT_TO_BACKEND", ReadOffset.lastConsumed()), 34 | streamListener 35 | ) 36 | listenerContainer.start() 37 | return subscription 38 | } 39 | } 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/src/main/kotlin/com/example/backend/service/RedisStreamConsumer.kt: -------------------------------------------------------------------------------- 1 | package com.example.backend.service 2 | 3 | import com.example.common.model.StreamDataEvent 4 | import org.slf4j.LoggerFactory 5 | import org.springframework.data.redis.connection.stream.ObjectRecord 6 | import org.springframework.data.redis.stream.StreamListener 7 | import org.springframework.stereotype.Service 8 | 9 | @Service 10 | class RedisStreamConsumer: StreamListener> { 11 | companion object { 12 | private val logger = LoggerFactory.getLogger(RedisStreamConsumer::class.java) 13 | } 14 | 15 | override fun onMessage(record: ObjectRecord?) { 16 | logger.info("[NEW] --> received message: ${record?.value} from stream: ${record?.stream}") 17 | } 18 | } 19 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/src/main/kotlin/com/example/backend/service/RedisStreamProducer.kt: -------------------------------------------------------------------------------- 1 | package com.example.backend.service 2 | 3 | import com.example.common.model.StreamDataEvent 4 | import org.slf4j.LoggerFactory 5 | import org.springframework.beans.factory.annotation.Value 6 | import org.springframework.data.redis.connection.stream.StreamRecords 7 | import org.springframework.data.redis.core.ReactiveRedisTemplate 8 | import org.springframework.scheduling.annotation.Scheduled 9 | import org.springframework.stereotype.Service 10 | import java.util.concurrent.atomic.AtomicInteger 11 | 12 | @Service 13 | class RedisStreamProducer( 14 | private val reactiveRedisTemplate: ReactiveRedisTemplate, 15 | @Value("\${spring.application.name}") private val applicationName: String, 16 | ) { 17 | companion object { 18 | private val atomicInteger = AtomicInteger(0) 19 | private val logger = LoggerFactory.getLogger(RedisStreamProducer::class.java) 20 | } 21 | 22 | fun publishEvent(streamTopic: String, data: StreamDataEvent) { 23 | val record = StreamRecords.newRecord().ofObject(data).withStreamKey(streamTopic) 24 | reactiveRedisTemplate.opsForStream().add(record).subscribe() 25 | } 26 | 27 | @Scheduled(initialDelay = 10000, fixedRate = 5000) 28 | fun publishTestMessageToBackend() { 29 | val data = StreamDataEvent( 30 | topic = "/topic/to-frontend", 31 | message = "New Message from $applicationName -- ID = ${atomicInteger.incrementAndGet()}" 32 | ) 33 | logger.info("Publishing Message: $data to Stream: TEST_EVENT_TO_WEBSOCKET_SERVER") 34 | publishEvent("TEST_EVENT_TO_WEBSOCKET_SERVER", data) 35 | } 36 | } 37 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/src/main/resources/application.yml: -------------------------------------------------------------------------------- 1 | ############################################################################################### 2 | # Server Configuration 3 | ############################################################################################### 4 | 5 | server.port: 18080 6 | spring.application.name: backend-service 7 | 8 | management: 9 | endpoints: 10 | enabled-by-default: true 11 | web.exposure.include: "*" 12 | endpoint.info.enabled: true 13 | 14 | spring: 15 | redis: 16 | host: localhost # Redis Server Host 17 | port: 6379 # Redis Server Port 18 | ssl: false # Enable SSL support 19 | database: 0 # database index -------------------------------------------------------------------------------- /02-scaling-websocket-server/backend-service/src/test/kotlin/com/example/backend/BackendApplicationTests.kt: -------------------------------------------------------------------------------- 1 | package com.example.backend 2 | 3 | import org.junit.jupiter.api.Test 4 | import org.springframework.boot.test.context.SpringBootTest 5 | 6 | @SpringBootTest 7 | class BackendApplicationTests { 8 | 9 | @Test 10 | fun contextLoads() { 11 | } 12 | 13 | } 14 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/build.gradle.kts: -------------------------------------------------------------------------------- 1 | plugins { 2 | base 3 | kotlin("jvm") version "1.5.31" apply false 4 | kotlin("plugin.spring") version "1.5.31" apply false 5 | } 6 | 7 | allprojects { 8 | group = "com.example" 9 | repositories { 10 | mavenCentral() 11 | } 12 | } 13 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/common-dto/.gitignore: -------------------------------------------------------------------------------- 1 | build -------------------------------------------------------------------------------- /02-scaling-websocket-server/common-dto/build.gradle.kts: -------------------------------------------------------------------------------- 1 | import org.jetbrains.kotlin.gradle.tasks.KotlinCompile 2 | 3 | plugins { 4 | id("java") 5 | id("org.springframework.boot") version "2.5.6" 6 | id("io.spring.dependency-management") version "1.0.11.RELEASE" 7 | kotlin("jvm") version "1.5.31" 8 | kotlin("plugin.spring") version "1.5.31" 9 | } 10 | 11 | group = "com.example" 12 | version = "0.0.1-SNAPSHOT" 13 | java.sourceCompatibility = JavaVersion.VERSION_11 14 | 15 | repositories { 16 | mavenCentral() 17 | } 18 | 19 | dependencies { 20 | // Spring Boot 21 | implementation("org.springframework.boot:spring-boot-starter") 22 | 23 | // Kotlin 24 | implementation("com.fasterxml.jackson.module:jackson-module-kotlin") 25 | implementation("org.jetbrains.kotlin:kotlin-reflect") 26 | implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8") 27 | } 28 | 29 | tasks.withType { 30 | kotlinOptions { 31 | freeCompilerArgs = listOf("-Xjsr305=strict") 32 | jvmTarget = "11" 33 | } 34 | } 35 | 36 | tasks.withType { 37 | useJUnitPlatform() 38 | } 39 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/common-dto/settings.gradle.kts: -------------------------------------------------------------------------------- 1 | rootProject.name = "common-dto" 2 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/common-dto/src/main/kotlin/com/example/common/model/StreamDataEvent.kt: -------------------------------------------------------------------------------- 1 | package com.example.common.model 2 | 3 | import com.fasterxml.jackson.annotation.JsonProperty 4 | 5 | data class StreamDataEvent ( 6 | @JsonProperty("message") val message: String, 7 | @JsonProperty("topic") val topic: String? = null, 8 | ) 9 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/common-dto/src/main/resources/application.yml: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/bkjam/websocket-microservice/92f437b892945a4285ef25fc704f514d14488eb5/02-scaling-websocket-server/common-dto/src/main/resources/application.yml -------------------------------------------------------------------------------- /02-scaling-websocket-server/gradle/wrapper/gradle-wrapper.jar: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/bkjam/websocket-microservice/92f437b892945a4285ef25fc704f514d14488eb5/02-scaling-websocket-server/gradle/wrapper/gradle-wrapper.jar -------------------------------------------------------------------------------- /02-scaling-websocket-server/gradle/wrapper/gradle-wrapper.properties: -------------------------------------------------------------------------------- 1 | distributionBase=GRADLE_USER_HOME 2 | distributionPath=wrapper/dists 3 | distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.1-bin.zip 4 | zipStoreBase=GRADLE_USER_HOME 5 | zipStorePath=wrapper/dists 6 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/gradlew: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | # 4 | # Copyright © 2015-2021 the original authors. 5 | # 6 | # Licensed under the Apache License, Version 2.0 (the "License"); 7 | # you may not use this file except in compliance with the License. 8 | # You may obtain a copy of the License at 9 | # 10 | # https://www.apache.org/licenses/LICENSE-2.0 11 | # 12 | # Unless required by applicable law or agreed to in writing, software 13 | # distributed under the License is distributed on an "AS IS" BASIS, 14 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 | # See the License for the specific language governing permissions and 16 | # limitations under the License. 17 | # 18 | 19 | ############################################################################## 20 | # 21 | # Gradle start up script for POSIX generated by Gradle. 22 | # 23 | # Important for running: 24 | # 25 | # (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is 26 | # noncompliant, but you have some other compliant shell such as ksh or 27 | # bash, then to run this script, type that shell name before the whole 28 | # command line, like: 29 | # 30 | # ksh Gradle 31 | # 32 | # Busybox and similar reduced shells will NOT work, because this script 33 | # requires all of these POSIX shell features: 34 | # * functions; 35 | # * expansions «$var», «${var}», «${var:-default}», «${var+SET}», 36 | # «${var#prefix}», «${var%suffix}», and «$( cmd )»; 37 | # * compound commands having a testable exit status, especially «case»; 38 | # * various built-in commands including «command», «set», and «ulimit». 39 | # 40 | # Important for patching: 41 | # 42 | # (2) This script targets any POSIX shell, so it avoids extensions provided 43 | # by Bash, Ksh, etc; in particular arrays are avoided. 44 | # 45 | # The "traditional" practice of packing multiple parameters into a 46 | # space-separated string is a well documented source of bugs and security 47 | # problems, so this is (mostly) avoided, by progressively accumulating 48 | # options in "$@", and eventually passing that to Java. 49 | # 50 | # Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS, 51 | # and GRADLE_OPTS) rely on word-splitting, this is performed explicitly; 52 | # see the in-line comments for details. 53 | # 54 | # There are tweaks for specific operating systems such as AIX, CygWin, 55 | # Darwin, MinGW, and NonStop. 56 | # 57 | # (3) This script is generated from the Groovy template 58 | # https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt 59 | # within the Gradle project. 60 | # 61 | # You can find Gradle at https://github.com/gradle/gradle/. 62 | # 63 | ############################################################################## 64 | 65 | # Attempt to set APP_HOME 66 | 67 | # Resolve links: $0 may be a link 68 | app_path=$0 69 | 70 | # Need this for daisy-chained symlinks. 71 | while 72 | APP_HOME=${app_path%"${app_path##*/}"} # leaves a trailing /; empty if no leading path 73 | [ -h "$app_path" ] 74 | do 75 | ls=$( ls -ld "$app_path" ) 76 | link=${ls#*' -> '} 77 | case $link in #( 78 | /*) app_path=$link ;; #( 79 | *) app_path=$APP_HOME$link ;; 80 | esac 81 | done 82 | 83 | APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit 84 | 85 | APP_NAME="Gradle" 86 | APP_BASE_NAME=${0##*/} 87 | 88 | # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. 89 | DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"' 90 | 91 | # Use the maximum available, or set MAX_FD != -1 to use that value. 92 | MAX_FD=maximum 93 | 94 | warn () { 95 | echo "$*" 96 | } >&2 97 | 98 | die () { 99 | echo 100 | echo "$*" 101 | echo 102 | exit 1 103 | } >&2 104 | 105 | # OS specific support (must be 'true' or 'false'). 106 | cygwin=false 107 | msys=false 108 | darwin=false 109 | nonstop=false 110 | case "$( uname )" in #( 111 | CYGWIN* ) cygwin=true ;; #( 112 | Darwin* ) darwin=true ;; #( 113 | MSYS* | MINGW* ) msys=true ;; #( 114 | NONSTOP* ) nonstop=true ;; 115 | esac 116 | 117 | CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar 118 | 119 | 120 | # Determine the Java command to use to start the JVM. 121 | if [ -n "$JAVA_HOME" ] ; then 122 | if [ -x "$JAVA_HOME/jre/sh/java" ] ; then 123 | # IBM's JDK on AIX uses strange locations for the executables 124 | JAVACMD=$JAVA_HOME/jre/sh/java 125 | else 126 | JAVACMD=$JAVA_HOME/bin/java 127 | fi 128 | if [ ! -x "$JAVACMD" ] ; then 129 | die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME 130 | 131 | Please set the JAVA_HOME variable in your environment to match the 132 | location of your Java installation." 133 | fi 134 | else 135 | JAVACMD=java 136 | which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 137 | 138 | Please set the JAVA_HOME variable in your environment to match the 139 | location of your Java installation." 140 | fi 141 | 142 | # Increase the maximum file descriptors if we can. 143 | if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then 144 | case $MAX_FD in #( 145 | max*) 146 | MAX_FD=$( ulimit -H -n ) || 147 | warn "Could not query maximum file descriptor limit" 148 | esac 149 | case $MAX_FD in #( 150 | '' | soft) :;; #( 151 | *) 152 | ulimit -n "$MAX_FD" || 153 | warn "Could not set maximum file descriptor limit to $MAX_FD" 154 | esac 155 | fi 156 | 157 | # Collect all arguments for the java command, stacking in reverse order: 158 | # * args from the command line 159 | # * the main class name 160 | # * -classpath 161 | # * -D...appname settings 162 | # * --module-path (only if needed) 163 | # * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables. 164 | 165 | # For Cygwin or MSYS, switch paths to Windows format before running java 166 | if "$cygwin" || "$msys" ; then 167 | APP_HOME=$( cygpath --path --mixed "$APP_HOME" ) 168 | CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" ) 169 | 170 | JAVACMD=$( cygpath --unix "$JAVACMD" ) 171 | 172 | # Now convert the arguments - kludge to limit ourselves to /bin/sh 173 | for arg do 174 | if 175 | case $arg in #( 176 | -*) false ;; # don't mess with options #( 177 | /?*) t=${arg#/} t=/${t%%/*} # looks like a POSIX filepath 178 | [ -e "$t" ] ;; #( 179 | *) false ;; 180 | esac 181 | then 182 | arg=$( cygpath --path --ignore --mixed "$arg" ) 183 | fi 184 | # Roll the args list around exactly as many times as the number of 185 | # args, so each arg winds up back in the position where it started, but 186 | # possibly modified. 187 | # 188 | # NB: a `for` loop captures its iteration list before it begins, so 189 | # changing the positional parameters here affects neither the number of 190 | # iterations, nor the values presented in `arg`. 191 | shift # remove old arg 192 | set -- "$@" "$arg" # push replacement arg 193 | done 194 | fi 195 | 196 | # Collect all arguments for the java command; 197 | # * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of 198 | # shell script including quotes and variable substitutions, so put them in 199 | # double quotes to make sure that they get re-expanded; and 200 | # * put everything else in single quotes, so that it's not re-expanded. 201 | 202 | set -- \ 203 | "-Dorg.gradle.appname=$APP_BASE_NAME" \ 204 | -classpath "$CLASSPATH" \ 205 | org.gradle.wrapper.GradleWrapperMain \ 206 | "$@" 207 | 208 | # Use "xargs" to parse quoted args. 209 | # 210 | # With -n1 it outputs one arg per line, with the quotes and backslashes removed. 211 | # 212 | # In Bash we could simply go: 213 | # 214 | # readarray ARGS < <( xargs -n1 <<<"$var" ) && 215 | # set -- "${ARGS[@]}" "$@" 216 | # 217 | # but POSIX shell has neither arrays nor command substitution, so instead we 218 | # post-process each arg (as a line of input to sed) to backslash-escape any 219 | # character that might be a shell metacharacter, then use eval to reverse 220 | # that process (while maintaining the separation between arguments), and wrap 221 | # the whole thing up as a single "set" statement. 222 | # 223 | # This will of course break if any of these variables contains a newline or 224 | # an unmatched quote. 225 | # 226 | 227 | eval "set -- $( 228 | printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" | 229 | xargs -n1 | 230 | sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' | 231 | tr '\n' ' ' 232 | )" '"$@"' 233 | 234 | exec "$JAVACMD" "$@" 235 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/gradlew.bat: -------------------------------------------------------------------------------- 1 | @rem 2 | @rem Copyright 2015 the original author or authors. 3 | @rem 4 | @rem Licensed under the Apache License, Version 2.0 (the "License"); 5 | @rem you may not use this file except in compliance with the License. 6 | @rem You may obtain a copy of the License at 7 | @rem 8 | @rem https://www.apache.org/licenses/LICENSE-2.0 9 | @rem 10 | @rem Unless required by applicable law or agreed to in writing, software 11 | @rem distributed under the License is distributed on an "AS IS" BASIS, 12 | @rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 | @rem See the License for the specific language governing permissions and 14 | @rem limitations under the License. 15 | @rem 16 | 17 | @if "%DEBUG%" == "" @echo off 18 | @rem ########################################################################## 19 | @rem 20 | @rem Gradle startup script for Windows 21 | @rem 22 | @rem ########################################################################## 23 | 24 | @rem Set local scope for the variables with windows NT shell 25 | if "%OS%"=="Windows_NT" setlocal 26 | 27 | set DIRNAME=%~dp0 28 | if "%DIRNAME%" == "" set DIRNAME=. 29 | set APP_BASE_NAME=%~n0 30 | set APP_HOME=%DIRNAME% 31 | 32 | @rem Resolve any "." and ".." in APP_HOME to make it shorter. 33 | for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi 34 | 35 | @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. 36 | set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m" 37 | 38 | @rem Find java.exe 39 | if defined JAVA_HOME goto findJavaFromJavaHome 40 | 41 | set JAVA_EXE=java.exe 42 | %JAVA_EXE% -version >NUL 2>&1 43 | if "%ERRORLEVEL%" == "0" goto execute 44 | 45 | echo. 46 | echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 47 | echo. 48 | echo Please set the JAVA_HOME variable in your environment to match the 49 | echo location of your Java installation. 50 | 51 | goto fail 52 | 53 | :findJavaFromJavaHome 54 | set JAVA_HOME=%JAVA_HOME:"=% 55 | set JAVA_EXE=%JAVA_HOME%/bin/java.exe 56 | 57 | if exist "%JAVA_EXE%" goto execute 58 | 59 | echo. 60 | echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 61 | echo. 62 | echo Please set the JAVA_HOME variable in your environment to match the 63 | echo location of your Java installation. 64 | 65 | goto fail 66 | 67 | :execute 68 | @rem Setup the command line 69 | 70 | set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar 71 | 72 | 73 | @rem Execute Gradle 74 | "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %* 75 | 76 | :end 77 | @rem End local scope for the variables with windows NT shell 78 | if "%ERRORLEVEL%"=="0" goto mainEnd 79 | 80 | :fail 81 | rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of 82 | rem the _cmd.exe /c_ return code! 83 | if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1 84 | exit /b 1 85 | 86 | :mainEnd 87 | if "%OS%"=="Windows_NT" endlocal 88 | 89 | :omega 90 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/settings.gradle.kts: -------------------------------------------------------------------------------- 1 | rootProject.name = "horizontal-scaling" 2 | 3 | // order does matters 4 | include("common-dto") 5 | include("backend-service") 6 | include("websocket-server") 7 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/.gitignore: -------------------------------------------------------------------------------- 1 | build -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/build.gradle.kts: -------------------------------------------------------------------------------- 1 | import org.jetbrains.kotlin.gradle.tasks.KotlinCompile 2 | 3 | plugins { 4 | id("org.springframework.boot") version "2.5.6" 5 | id("io.spring.dependency-management") version "1.0.11.RELEASE" 6 | kotlin("jvm") version "1.5.31" 7 | kotlin("plugin.spring") version "1.5.31" 8 | } 9 | 10 | group = "com.example" 11 | version = "0.0.1-SNAPSHOT" 12 | java.sourceCompatibility = JavaVersion.VERSION_11 13 | 14 | repositories { 15 | mavenCentral() 16 | } 17 | 18 | dependencies { 19 | // Dto 20 | implementation(project(":common-dto")) 21 | 22 | // Spring Boot 23 | implementation("org.springframework.boot:spring-boot-starter-actuator") 24 | implementation("org.springframework.boot:spring-boot-starter-webflux") 25 | implementation("org.springframework.boot:spring-boot-starter-data-redis-reactive") 26 | implementation("org.springframework.boot:spring-boot-starter-websocket") 27 | 28 | // Kotlin 29 | implementation("com.fasterxml.jackson.module:jackson-module-kotlin") 30 | implementation("org.jetbrains.kotlin:kotlin-reflect") 31 | implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8") 32 | 33 | // Testing 34 | testImplementation("org.springframework.boot:spring-boot-starter-test") 35 | testImplementation("io.projectreactor:reactor-test") 36 | } 37 | 38 | tasks.bootRun { 39 | if (project.hasProperty("args")) { 40 | args(project.properties["args"].toString().split(",")) 41 | } 42 | } 43 | 44 | tasks.withType { 45 | kotlinOptions { 46 | freeCompilerArgs = listOf("-Xjsr305=strict") 47 | jvmTarget = "11" 48 | } 49 | } 50 | 51 | tasks.withType { 52 | useJUnitPlatform() 53 | } 54 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/settings.gradle.kts: -------------------------------------------------------------------------------- 1 | rootProject.name = "websocker-server" 2 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/WebsocketServerApplication.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket 2 | 3 | import org.springframework.boot.autoconfigure.SpringBootApplication 4 | import org.springframework.boot.runApplication 5 | import org.springframework.scheduling.annotation.EnableScheduling 6 | 7 | @EnableScheduling 8 | @SpringBootApplication 9 | class WebsocketServerApplication 10 | 11 | fun main(args: Array) { 12 | runApplication(*args) 13 | } 14 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/config/RedisConfig.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.config 2 | 3 | import com.example.websocket.model.BroadcastEvent 4 | import org.springframework.context.annotation.Bean 5 | import org.springframework.context.annotation.Configuration 6 | import org.springframework.data.redis.connection.ReactiveKeyCommands 7 | import org.springframework.data.redis.connection.ReactiveRedisConnectionFactory 8 | import org.springframework.data.redis.connection.ReactiveStringCommands 9 | import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory 10 | import org.springframework.data.redis.core.ReactiveRedisTemplate 11 | import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer 12 | import org.springframework.data.redis.serializer.RedisSerializationContext 13 | import org.springframework.data.redis.serializer.StringRedisSerializer 14 | 15 | @Configuration 16 | class RedisConfig { 17 | @Bean 18 | fun reactiveRedisTemplate(factory: LettuceConnectionFactory): ReactiveRedisTemplate { 19 | val serializer = Jackson2JsonRedisSerializer(BroadcastEvent::class.java) 20 | val builder = RedisSerializationContext.newSerializationContext(StringRedisSerializer()) 21 | val context = builder.value(serializer).build() 22 | return ReactiveRedisTemplate(factory, context) 23 | } 24 | 25 | @Bean 26 | fun keyCommands(reactiveRedisConnectionFactory: ReactiveRedisConnectionFactory): ReactiveKeyCommands { 27 | return reactiveRedisConnectionFactory.reactiveConnection.keyCommands() 28 | } 29 | 30 | @Bean 31 | fun stringCommands(reactiveRedisConnectionFactory: ReactiveRedisConnectionFactory): ReactiveStringCommands { 32 | return reactiveRedisConnectionFactory.reactiveConnection.stringCommands() 33 | } 34 | } 35 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/config/RedisStreamConfig.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.config 2 | 3 | import com.example.common.model.StreamDataEvent 4 | import org.springframework.context.annotation.Bean 5 | import org.springframework.context.annotation.Configuration 6 | import org.springframework.data.redis.connection.RedisConnectionFactory 7 | import org.springframework.data.redis.connection.stream.ObjectRecord 8 | import org.springframework.data.redis.connection.stream.StreamOffset 9 | import org.springframework.data.redis.stream.StreamListener 10 | import org.springframework.data.redis.stream.StreamMessageListenerContainer 11 | import org.springframework.data.redis.stream.Subscription 12 | import java.time.Duration 13 | 14 | @Configuration 15 | class RedisStreamConfig(private val streamListener: StreamListener>) { 16 | 17 | private fun initListenerContainer(redisConnectionFactory: RedisConnectionFactory): StreamMessageListenerContainer> { 18 | val options = StreamMessageListenerContainer 19 | .StreamMessageListenerContainerOptions 20 | .builder() 21 | .pollTimeout(Duration.ofSeconds(1)) 22 | .targetType(StreamDataEvent::class.java) 23 | .build() 24 | return StreamMessageListenerContainer.create(redisConnectionFactory, options) 25 | } 26 | 27 | @Bean("TestEventSubscription") 28 | fun subscription(redisConnectionFactory: RedisConnectionFactory): Subscription { 29 | val listenerContainer = initListenerContainer(redisConnectionFactory) 30 | val subscription = listenerContainer.receive(StreamOffset.latest("TEST_EVENT_TO_WEBSOCKET_SERVER"), streamListener) 31 | listenerContainer.start() 32 | return subscription 33 | } 34 | } 35 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/config/WebSocketConfig.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.config 2 | 3 | import org.springframework.context.annotation.Configuration 4 | import org.springframework.messaging.simp.config.MessageBrokerRegistry 5 | import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker 6 | import org.springframework.web.socket.config.annotation.StompEndpointRegistry 7 | import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer 8 | 9 | @Configuration 10 | @EnableWebSocketMessageBroker 11 | class WebSocketConfig: WebSocketMessageBrokerConfigurer { 12 | override fun registerStompEndpoints(registry: StompEndpointRegistry) { 13 | registry.addEndpoint("/stomp").setAllowedOrigins("*") 14 | } 15 | 16 | override fun configureMessageBroker(registry: MessageBrokerRegistry) { 17 | registry.enableSimpleBroker("/topic") 18 | registry.setApplicationDestinationPrefixes("/app") 19 | } 20 | } 21 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/controller/NotificationController.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.controller 2 | 3 | import com.example.websocket.model.BroadcastEvent 4 | import com.example.websocket.model.NewMessageRequest 5 | import com.example.websocket.service.RedisBroadcastService 6 | import org.springframework.web.bind.annotation.* 7 | 8 | @RestController 9 | @RequestMapping("/api/notification") 10 | class NotificationController(private val redisBroadcastService: RedisBroadcastService) { 11 | @PostMapping 12 | fun newMessage(@RequestBody request: NewMessageRequest) { 13 | val event = BroadcastEvent(request.topic, request.message) 14 | redisBroadcastService.publish(event) 15 | } 16 | } 17 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/controller/WebsocketController.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.controller 2 | 3 | import com.example.common.model.StreamDataEvent 4 | import com.example.websocket.service.RedisStreamProducer 5 | import org.springframework.messaging.handler.annotation.MessageMapping 6 | import org.springframework.messaging.handler.annotation.Payload 7 | import org.springframework.stereotype.Controller 8 | 9 | @Controller 10 | class WebsocketController(private val redisStreamProducer: RedisStreamProducer) { 11 | @MessageMapping("/test") 12 | fun greetMessage(@Payload message: String) { 13 | val event = StreamDataEvent(message) 14 | redisStreamProducer.publishEvent("TEST_EVENT_TO_BACKEND", event) 15 | } 16 | } 17 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/model/BroadcastEvent.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.model 2 | 3 | import com.fasterxml.jackson.annotation.JsonProperty 4 | import java.io.Serializable 5 | 6 | data class BroadcastEvent( 7 | @JsonProperty("topic") val topic: String, 8 | @JsonProperty("message") val message: String 9 | ): Serializable 10 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/model/NewMessageRequest.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.model 2 | 3 | data class NewMessageRequest( 4 | val topic: String, 5 | val message: String 6 | ) 7 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/service/RedisBroadcastService.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.service 2 | 3 | import com.example.websocket.model.BroadcastEvent 4 | import org.slf4j.LoggerFactory 5 | import org.springframework.data.redis.connection.ReactiveSubscription 6 | import org.springframework.data.redis.core.ReactiveRedisTemplate 7 | import org.springframework.data.redis.listener.ChannelTopic 8 | import org.springframework.messaging.simp.SimpMessagingTemplate 9 | import org.springframework.stereotype.Service 10 | import javax.annotation.PostConstruct 11 | 12 | @Service 13 | class RedisBroadcastService( 14 | private val reactiveRedisTemplate: ReactiveRedisTemplate, 15 | private val websocketTemplate: SimpMessagingTemplate 16 | ) { 17 | companion object { 18 | private const val broadcastChannel = "BROADCAST-CHANNEL" 19 | private val logger = LoggerFactory.getLogger(RedisBroadcastService::class.java) 20 | } 21 | 22 | fun publish(event: BroadcastEvent) { 23 | logger.info("Broadcasting event... $event") 24 | reactiveRedisTemplate.convertAndSend(broadcastChannel, event).subscribe() 25 | } 26 | 27 | @PostConstruct 28 | fun subscribe() { 29 | reactiveRedisTemplate.listenTo(ChannelTopic.of(broadcastChannel)) 30 | .map(ReactiveSubscription.Message::getMessage) 31 | .subscribe { message -> 32 | websocketTemplate.convertAndSend(message.topic, message.message) 33 | } 34 | } 35 | } 36 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/service/RedisStreamConsumer.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.service 2 | 3 | import com.example.common.model.StreamDataEvent 4 | import org.slf4j.LoggerFactory 5 | import org.springframework.data.redis.connection.stream.ObjectRecord 6 | import org.springframework.data.redis.stream.StreamListener 7 | import org.springframework.messaging.simp.SimpMessagingTemplate 8 | import org.springframework.stereotype.Service 9 | 10 | @Service 11 | class RedisStreamConsumer( 12 | private val websocketTemplate: SimpMessagingTemplate 13 | ): StreamListener> { 14 | companion object { 15 | private val logger = LoggerFactory.getLogger(RedisStreamConsumer::class.java) 16 | } 17 | 18 | override fun onMessage(record: ObjectRecord) { 19 | logger.info("[NEW] --> received message: ${record.value} from stream: ${record.stream}") 20 | record.value.topic?.let { destination -> 21 | websocketTemplate.convertAndSend(destination, record.value.message) 22 | } 23 | } 24 | } 25 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/kotlin/com/example/websocket/service/RedisStreamProducer.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket.service 2 | 3 | import com.example.common.model.StreamDataEvent 4 | import org.slf4j.LoggerFactory 5 | import org.springframework.beans.factory.annotation.Value 6 | import org.springframework.data.redis.connection.stream.StreamRecords 7 | import org.springframework.data.redis.core.ReactiveRedisTemplate 8 | import org.springframework.scheduling.annotation.Scheduled 9 | import org.springframework.stereotype.Service 10 | import java.util.concurrent.atomic.AtomicInteger 11 | 12 | @Service 13 | class RedisStreamProducer( 14 | private val reactiveRedisTemplate: ReactiveRedisTemplate, 15 | @Value("\${spring.application.name}") private val applicationName: String, 16 | ) { 17 | companion object { 18 | private val atomicInteger = AtomicInteger(0) 19 | private val logger = LoggerFactory.getLogger(RedisStreamProducer::class.java) 20 | } 21 | 22 | fun publishEvent(streamTopic: String, data: StreamDataEvent) { 23 | val record = StreamRecords.newRecord().ofObject(data).withStreamKey(streamTopic) 24 | reactiveRedisTemplate.opsForStream().add(record).subscribe() 25 | } 26 | 27 | @Scheduled(initialDelay = 10000, fixedRate = 5000) 28 | fun publishTestMessageToBackend() { 29 | val data = StreamDataEvent(message = "New Message from $applicationName -- ID = ${atomicInteger.incrementAndGet()}") 30 | logger.info("Publishing Message: $data to Stream: TEST_EVENT_TO_BACKEND") 31 | publishEvent("TEST_EVENT_TO_BACKEND", data) 32 | } 33 | } 34 | -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/main/resources/application.yml: -------------------------------------------------------------------------------- 1 | ############################################################################################### 2 | # Server Configuration 3 | ############################################################################################### 4 | 5 | server.port: 8080 6 | spring.application.name: websocket-server 7 | 8 | logging.level: 9 | root: INFO 10 | org.springframework.web: INFO 11 | org.springframework.web.HttpLogging: INFO 12 | com.example.websocket: DEBUG 13 | 14 | spring.redis: 15 | host: localhost # Redis Server Host 16 | port: 6379 # Redis Server Port 17 | ssl: false # Enable SSL support 18 | database: 0 # database index -------------------------------------------------------------------------------- /02-scaling-websocket-server/websocket-server/src/test/kotlin/com/example/websocket/WebsocketServerApplicationTests.kt: -------------------------------------------------------------------------------- 1 | package com.example.websocket 2 | 3 | import org.junit.jupiter.api.Test 4 | import org.springframework.boot.test.context.SpringBootTest 5 | 6 | @SpringBootTest 7 | class WebsocketServerApplicationTests { 8 | 9 | @Test 10 | fun contextLoads() { 11 | } 12 | 13 | } 14 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. Definitions. 8 | 9 | "License" shall mean the terms and conditions for use, reproduction, 10 | and distribution as defined by Sections 1 through 9 of this document. 11 | 12 | "Licensor" shall mean the copyright owner or entity authorized by 13 | the copyright owner that is granting the License. 14 | 15 | "Legal Entity" shall mean the union of the acting entity and all 16 | other entities that control, are controlled by, or are under common 17 | control with that entity. For the purposes of this definition, 18 | "control" means (i) the power, direct or indirect, to cause the 19 | direction or management of such entity, whether by contract or 20 | otherwise, or (ii) ownership of fifty percent (50%) or more of the 21 | outstanding shares, or (iii) beneficial ownership of such entity. 22 | 23 | "You" (or "Your") shall mean an individual or Legal Entity 24 | exercising permissions granted by this License. 25 | 26 | "Source" form shall mean the preferred form for making modifications, 27 | including but not limited to software source code, documentation 28 | source, and configuration files. 29 | 30 | "Object" form shall mean any form resulting from mechanical 31 | transformation or translation of a Source form, including but 32 | not limited to compiled object code, generated documentation, 33 | and conversions to other media types. 34 | 35 | "Work" shall mean the work of authorship, whether in Source or 36 | Object form, made available under the License, as indicated by a 37 | copyright notice that is included in or attached to the work 38 | (an example is provided in the Appendix below). 39 | 40 | "Derivative Works" shall mean any work, whether in Source or Object 41 | form, that is based on (or derived from) the Work and for which the 42 | editorial revisions, annotations, elaborations, or other modifications 43 | represent, as a whole, an original work of authorship. For the purposes 44 | of this License, Derivative Works shall not include works that remain 45 | separable from, or merely link (or bind by name) to the interfaces of, 46 | the Work and Derivative Works thereof. 47 | 48 | "Contribution" shall mean any work of authorship, including 49 | the original version of the Work and any modifications or additions 50 | to that Work or Derivative Works thereof, that is intentionally 51 | submitted to Licensor for inclusion in the Work by the copyright owner 52 | or by an individual or Legal Entity authorized to submit on behalf of 53 | the copyright owner. For the purposes of this definition, "submitted" 54 | means any form of electronic, verbal, or written communication sent 55 | to the Licensor or its representatives, including but not limited to 56 | communication on electronic mailing lists, source code control systems, 57 | and issue tracking systems that are managed by, or on behalf of, the 58 | Licensor for the purpose of discussing and improving the Work, but 59 | excluding communication that is conspicuously marked or otherwise 60 | designated in writing by the copyright owner as "Not a Contribution." 61 | 62 | "Contributor" shall mean Licensor and any individual or Legal Entity 63 | on behalf of whom a Contribution has been received by Licensor and 64 | subsequently incorporated within the Work. 65 | 66 | 2. Grant of Copyright License. Subject to the terms and conditions of 67 | this License, each Contributor hereby grants to You a perpetual, 68 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 69 | copyright license to reproduce, prepare Derivative Works of, 70 | publicly display, publicly perform, sublicense, and distribute the 71 | Work and such Derivative Works in Source or Object form. 72 | 73 | 3. Grant of Patent License. Subject to the terms and conditions of 74 | this License, each Contributor hereby grants to You a perpetual, 75 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 76 | (except as stated in this section) patent license to make, have made, 77 | use, offer to sell, sell, import, and otherwise transfer the Work, 78 | where such license applies only to those patent claims licensable 79 | by such Contributor that are necessarily infringed by their 80 | Contribution(s) alone or by combination of their Contribution(s) 81 | with the Work to which such Contribution(s) was submitted. If You 82 | institute patent litigation against any entity (including a 83 | cross-claim or counterclaim in a lawsuit) alleging that the Work 84 | or a Contribution incorporated within the Work constitutes direct 85 | or contributory patent infringement, then any patent licenses 86 | granted to You under this License for that Work shall terminate 87 | as of the date such litigation is filed. 88 | 89 | 4. Redistribution. You may reproduce and distribute copies of the 90 | Work or Derivative Works thereof in any medium, with or without 91 | modifications, and in Source or Object form, provided that You 92 | meet the following conditions: 93 | 94 | (a) You must give any other recipients of the Work or 95 | Derivative Works a copy of this License; and 96 | 97 | (b) You must cause any modified files to carry prominent notices 98 | stating that You changed the files; and 99 | 100 | (c) You must retain, in the Source form of any Derivative Works 101 | that You distribute, all copyright, patent, trademark, and 102 | attribution notices from the Source form of the Work, 103 | excluding those notices that do not pertain to any part of 104 | the Derivative Works; and 105 | 106 | (d) If the Work includes a "NOTICE" text file as part of its 107 | distribution, then any Derivative Works that You distribute must 108 | include a readable copy of the attribution notices contained 109 | within such NOTICE file, excluding those notices that do not 110 | pertain to any part of the Derivative Works, in at least one 111 | of the following places: within a NOTICE text file distributed 112 | as part of the Derivative Works; within the Source form or 113 | documentation, if provided along with the Derivative Works; or, 114 | within a display generated by the Derivative Works, if and 115 | wherever such third-party notices normally appear. The contents 116 | of the NOTICE file are for informational purposes only and 117 | do not modify the License. You may add Your own attribution 118 | notices within Derivative Works that You distribute, alongside 119 | or as an addendum to the NOTICE text from the Work, provided 120 | that such additional attribution notices cannot be construed 121 | as modifying the License. 122 | 123 | You may add Your own copyright statement to Your modifications and 124 | may provide additional or different license terms and conditions 125 | for use, reproduction, or distribution of Your modifications, or 126 | for any such Derivative Works as a whole, provided Your use, 127 | reproduction, and distribution of the Work otherwise complies with 128 | the conditions stated in this License. 129 | 130 | 5. Submission of Contributions. Unless You explicitly state otherwise, 131 | any Contribution intentionally submitted for inclusion in the Work 132 | by You to the Licensor shall be under the terms and conditions of 133 | this License, without any additional terms or conditions. 134 | Notwithstanding the above, nothing herein shall supersede or modify 135 | the terms of any separate license agreement you may have executed 136 | with Licensor regarding such Contributions. 137 | 138 | 6. Trademarks. This License does not grant permission to use the trade 139 | names, trademarks, service marks, or product names of the Licensor, 140 | except as required for reasonable and customary use in describing the 141 | origin of the Work and reproducing the content of the NOTICE file. 142 | 143 | 7. Disclaimer of Warranty. Unless required by applicable law or 144 | agreed to in writing, Licensor provides the Work (and each 145 | Contributor provides its Contributions) on an "AS IS" BASIS, 146 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 147 | implied, including, without limitation, any warranties or conditions 148 | of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A 149 | PARTICULAR PURPOSE. You are solely responsible for determining the 150 | appropriateness of using or redistributing the Work and assume any 151 | risks associated with Your exercise of permissions under this License. 152 | 153 | 8. Limitation of Liability. In no event and under no legal theory, 154 | whether in tort (including negligence), contract, or otherwise, 155 | unless required by applicable law (such as deliberate and grossly 156 | negligent acts) or agreed to in writing, shall any Contributor be 157 | liable to You for damages, including any direct, indirect, special, 158 | incidental, or consequential damages of any character arising as a 159 | result of this License or out of the use or inability to use the 160 | Work (including but not limited to damages for loss of goodwill, 161 | work stoppage, computer failure or malfunction, or any and all 162 | other commercial damages or losses), even if such Contributor 163 | has been advised of the possibility of such damages. 164 | 165 | 9. Accepting Warranty or Additional Liability. While redistributing 166 | the Work or Derivative Works thereof, You may choose to offer, 167 | and charge a fee for, acceptance of support, warranty, indemnity, 168 | or other liability obligations and/or rights consistent with this 169 | License. However, in accepting such obligations, You may act only 170 | on Your own behalf and on Your sole responsibility, not on behalf 171 | of any other Contributor, and only if You agree to indemnify, 172 | defend, and hold each Contributor harmless for any liability 173 | incurred by, or claims asserted against, such Contributor by reason 174 | of your accepting any such warranty or additional liability. 175 | 176 | END OF TERMS AND CONDITIONS 177 | 178 | APPENDIX: How to apply the Apache License to your work. 179 | 180 | To apply the Apache License to your work, attach the following 181 | boilerplate notice, with the fields enclosed by brackets "[]" 182 | replaced with your own identifying information. (Don't include 183 | the brackets!) The text should be enclosed in the appropriate 184 | comment syntax for the file format. We also recommend that a 185 | file or class name and description of purpose be included on the 186 | same "printed page" as the copyright notice for easier 187 | identification within third-party archives. 188 | 189 | Copyright [yyyy] [name of copyright owner] 190 | 191 | Licensed under the Apache License, Version 2.0 (the "License"); 192 | you may not use this file except in compliance with the License. 193 | You may obtain a copy of the License at 194 | 195 | http://www.apache.org/licenses/LICENSE-2.0 196 | 197 | Unless required by applicable law or agreed to in writing, software 198 | distributed under the License is distributed on an "AS IS" BASIS, 199 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 200 | See the License for the specific language governing permissions and 201 | limitations under the License. 202 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Websocket Microservice Exploration 2 | 3 | This is an exploration on Websocket Server for real-time communication between Frontend and Backend. 4 | 5 | | Article | Sample Codes | 6 | | --- | --- | 7 | | [Building a Websocket Server in Microservice Architecture](https://betterprogramming.pub/building-a-websocket-server-in-a-microservice-architecture-50c6c6432e2b) | [01-basic-websocket-server](01-basic-websocket-server) | 8 | | [Design Considerations for Scaling Websocket Server Horizontally with Publish-Subscribe Pattern](https://betterprogramming.pub/design-considerations-for-scaling-websocket-server-horizontally-with-a-publish-subscribe-pattern-fe6de9988400)
[Implement a Scalable WebSocket Server with Spring Boot, Redis Pub/Sub, and Redis Streams](https://betterprogramming.pub/implement-a-scalable-websocket-server-with-spring-boot-redis-pub-sub-and-redis-streams-b6b8cc08767f) | [02-scaling-websocket-server](02-scaling-websocket-server) | 9 | -------------------------------------------------------------------------------- /docs/diagram.drawio: -------------------------------------------------------------------------------- 1 | 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 --------------------------------------------------------------------------------