├── .gitignore
├── README.md
├── demo-go-sink
├── consumer.go
├── main.go
└── model.go
├── demo-java-source
├── build.gradle
├── gradle
│ └── wrapper
│ │ ├── gradle-wrapper.jar
│ │ └── gradle-wrapper.properties
├── gradlew
├── gradlew.bat
└── src
│ ├── main
│ ├── java
│ │ └── com
│ │ │ └── example
│ │ │ ├── MessageDto.java
│ │ │ ├── SampleSource.java
│ │ │ └── StreamApplication.java
│ └── resources
│ │ └── application.properties
│ └── test
│ └── java
│ └── com
│ └── example
│ └── DemoApplicationTests.java
└── demo-kotlin-sink
├── build.gradle
├── gradle
└── wrapper
│ ├── gradle-wrapper.jar
│ └── gradle-wrapper.properties
├── gradlew
├── gradlew.bat
├── settings.gradle
└── src
└── main
├── kotlin
└── com
│ └── example
│ ├── SampleSink.kt
│ └── SinkApplication.kt
└── resources
└── application.properties
/.gitignore:
--------------------------------------------------------------------------------
1 | # Created by .ignore support plugin (hsz.mobi)
2 | ### Gradle template
3 | .gradle
4 | /build/
5 |
6 | # Ignore Gradle GUI config
7 | gradle-app.setting
8 |
9 | # Avoid ignoring Gradle wrapper jar file (.jar files are usually ignored)
10 | !gradle-wrapper.jar
11 |
12 | # Cache of project
13 | .gradletasknamecache
14 |
15 | # # Work around https://youtrack.jetbrains.com/issue/IDEA-116898
16 | # gradle/wrapper/gradle-wrapper.properties
17 | ### JetBrains template
18 | # Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
19 | # Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
20 |
21 | # User-specific stuff:
22 | .idea/workspace.xml
23 | .idea/tasks.xml
24 | .idea/*
25 |
26 | # Sensitive or high-churn files:
27 | .idea/dataSources/
28 | .idea/dataSources.ids
29 | .idea/dataSources.xml
30 | .idea/dataSources.local.xml
31 | .idea/sqlDataSources.xml
32 | .idea/dynamic.xml
33 | .idea/uiDesigner.xml
34 | *idea*
35 |
36 | # Gradle:
37 | .idea/gradle.xml
38 | .idea/libraries
39 | build
40 | target
41 | lib
42 |
43 | # Mongo Explorer plugin:
44 | .idea/mongoSettings.xml
45 |
46 | ## File-based project format:
47 | *.iws
48 |
49 | ## Plugin-specific files:
50 |
51 | # IntelliJ
52 | /out/
53 |
54 | # mpeltonen/sbt-idea plugin
55 | .idea_modules/
56 |
57 | # JIRA plugin
58 | atlassian-ide-plugin.xml
59 |
60 | # Crashlytics plugin (for Android Studio and IntelliJ)
61 | com_crashlytics_export_strings.xml
62 | crashlytics.properties
63 | crashlytics-build.properties
64 | fabric.properties
65 |
66 |
--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
1 | # About
2 | 'Hello world' Kafka integration of Java, Kotlin and Go apps
3 |
4 | - demo-java-source with Spring Cloud Stream - localhost:8080
5 | - demo-kotlin-sink with Spring Cloud Stream - localhost:8081 (Consumer)
6 | - demo-go-sink with Shopify/sarama (Kafka Client) - localhost:8082 (Consumer)
7 | - Apache Kafka as Message Broker
8 | - Go Http/2 Push example (just for fun)
9 |
10 | Running Kafka from docker:
11 | ```
12 | docker run --name spotifykafka -p 2181:2181 -p 9092:9092 --env ADVERTISED_HOST=localhost --env ADVERTISED_PORT=9092 spotify/kafka
13 | ```
14 |
15 | to get Shopify/sarama lib:
16 | ```
17 | go get github.com/Shopify/sarama
18 | ```
19 |
20 | # How to run
21 | 1. Run docker spotify/kafka
22 | 1. Run Java/Kotlin/Go app from IDE (Prefer IDEA & Gogland)
23 | 1. Send request to Java Source App - POST http://localhost:8080/message {"name": "Krzysztof"}
24 | 1. Both Go and Kotlin app will print the messages on their consoles, something like this:
25 | ```
26 | INFO 22360 --- [afka-listener-1] com.example.SampleSink Kotlin received: Krzysztof
27 | ```
28 |
29 | ```
30 | Golang received: Krzysztof
31 |
32 | ```
33 | # Http/2 Go Push
34 | 1. Go 1.8beta2 required
35 | 1. Run crypto/tls/generate_cert.go to generate cert.pem and key.pem. and put them to the project
36 | 1. Go to https://localhost:8082/ (yes https)
37 | 1. Resources will be pushed to browser, check Network (devtools)
38 |
39 |
40 | # References
41 | 1. https://medium.com/@Oskarr3/implementing-cqrs-using-kafka-and-sarama-library-in-golang-da7efa3b77fe#.razrnz8eh
42 | 1. https://blog.codecentric.de/en/2016/04/event-driven-microservices-spring-cloud-stream/
43 | 1. [Go 1.8 Http/2 Push](https://gist.github.com/rakyll/eec415977f85d50a493ca8472ba97b68)
44 |
45 | # TODO
46 | 1. Make it more interesting... because printing to console is not cool enough ;)
47 | 1. Add SSE/ Websockets ?
48 |
49 |
50 |
--------------------------------------------------------------------------------
/demo-go-sink/consumer.go:
--------------------------------------------------------------------------------
1 | package main
2 |
3 | import (
4 | "fmt"
5 |
6 | "encoding/json"
7 |
8 | "github.com/Shopify/sarama"
9 | )
10 |
11 | var brokers = []string{"localhost:9092"}
12 |
13 | type Message struct {
14 | Name string `json:"name"`
15 | }
16 |
17 | func subscribe(topic string, consumer sarama.Consumer) {
18 | partitionList, err := consumer.Partitions(topic) //get all partitions on the given topic
19 | if err != nil {
20 | fmt.Println("Error retrieving partitionList ", err)
21 | }
22 | initialOffset := sarama.OffsetNewest //get offset for the newest message on the topic
23 |
24 | for _, partition := range partitionList {
25 | pc, _ := consumer.ConsumePartition(topic, partition, initialOffset)
26 |
27 | go func(pc sarama.PartitionConsumer) {
28 | for message := range pc.Messages() {
29 | messageReceived(message)
30 | }
31 | }(pc)
32 | }
33 | }
34 |
35 | func messageReceived(message *sarama.ConsumerMessage) {
36 | var m Message
37 |
38 | err := json.Unmarshal(message.Value, &m)
39 | if err != nil {
40 | println("JSON parsing error ", err)
41 | }
42 | println("Golang received: " + m.Name)
43 |
44 | saveMessage(m.Name)
45 | }
46 |
--------------------------------------------------------------------------------
/demo-go-sink/main.go:
--------------------------------------------------------------------------------
1 | package main
2 |
3 | import (
4 | "fmt"
5 | "log"
6 | "net/http"
7 |
8 | "github.com/Shopify/sarama"
9 | )
10 |
11 | const (
12 | topic = "messages"
13 | contentType = "Content-Type"
14 | applicationJSON = "application/json"
15 | )
16 |
17 | func html(text string) string {
18 | html := `
19 |
20 | Hello
21 |
22 |
23 | Received: ` + text +
24 | `
25 |
26 | `
27 | return html
28 |
29 | }
30 |
31 | func main() {
32 | http.HandleFunc("/main.js", func(w http.ResponseWriter, r *http.Request) {
33 |
34 | mainJS := `alert("` + getMessage() + `");`
35 | fmt.Fprintf(w, mainJS)
36 | })
37 | http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
38 | if r.URL.Path != "/" {
39 | http.NotFound(w, r)
40 | return
41 | }
42 | pusher, ok := w.(http.Pusher)
43 | if ok {
44 | if err := pusher.Push("/main.js", nil); err != nil {
45 | log.Printf("Failed to push: %v", err)
46 | }
47 | }
48 | fmt.Fprintf(w, html(getMessage()))
49 | })
50 |
51 | config := sarama.NewConfig()
52 | config.Consumer.Return.Errors = true
53 | consumer, err := sarama.NewConsumer(brokers, config)
54 | if err != nil {
55 | fmt.Println("Could not create consumer: ", err)
56 | }
57 | subscribe(topic, consumer)
58 |
59 | log.Fatal(http.ListenAndServeTLS(":8082", "cert.pem", "key.pem", nil))
60 | }
61 |
--------------------------------------------------------------------------------
/demo-go-sink/model.go:
--------------------------------------------------------------------------------
1 | package main
2 |
3 | var message string
4 |
5 | func saveMessage(text string) { message = text }
6 |
7 | func getMessage() string { return message }
8 |
--------------------------------------------------------------------------------
/demo-java-source/build.gradle:
--------------------------------------------------------------------------------
1 | buildscript {
2 | ext {
3 | springBootVersion = '1.4.3.RELEASE'
4 | }
5 | repositories {
6 | mavenCentral()
7 | }
8 | dependencies {
9 | classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
10 | }
11 | }
12 |
13 | apply plugin: 'java'
14 | apply plugin: 'eclipse'
15 | apply plugin: 'org.springframework.boot'
16 |
17 | jar {
18 | baseName = 'demo-java-source'
19 | version = '0.0.1-SNAPSHOT'
20 | }
21 |
22 | sourceCompatibility = 1.8
23 |
24 | repositories {
25 | mavenCentral()
26 | }
27 |
28 |
29 | dependencies {
30 | compile('org.springframework.cloud:spring-cloud-starter-stream-kafka')
31 | testCompile('org.springframework.boot:spring-boot-starter-test')
32 | }
33 |
34 | dependencyManagement {
35 | imports {
36 | mavenBom "org.springframework.cloud:spring-cloud-dependencies:Camden.SR3"
37 | }
38 | }
39 |
--------------------------------------------------------------------------------
/demo-java-source/gradle/wrapper/gradle-wrapper.jar:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/kgoralski/go-kotlin-java-kafka/342ba9d8ddea7cece2b9f155fca9522327c2fe68/demo-java-source/gradle/wrapper/gradle-wrapper.jar
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/demo-java-source/gradle/wrapper/gradle-wrapper.properties:
--------------------------------------------------------------------------------
1 | distributionBase=GRADLE_USER_HOME
2 | distributionPath=wrapper/dists
3 | zipStoreBase=GRADLE_USER_HOME
4 | zipStorePath=wrapper/dists
5 | distributionUrl=https\://services.gradle.org/distributions/gradle-2.13-bin.zip
6 |
--------------------------------------------------------------------------------
/demo-java-source/gradlew:
--------------------------------------------------------------------------------
1 | #!/usr/bin/env bash
2 |
3 | ##############################################################################
4 | ##
5 | ## Gradle start up script for UN*X
6 | ##
7 | ##############################################################################
8 |
9 | # Attempt to set APP_HOME
10 | # Resolve links: $0 may be a link
11 | PRG="$0"
12 | # Need this for relative symlinks.
13 | while [ -h "$PRG" ] ; do
14 | ls=`ls -ld "$PRG"`
15 | link=`expr "$ls" : '.*-> \(.*\)$'`
16 | if expr "$link" : '/.*' > /dev/null; then
17 | PRG="$link"
18 | else
19 | PRG=`dirname "$PRG"`"/$link"
20 | fi
21 | done
22 | SAVED="`pwd`"
23 | cd "`dirname \"$PRG\"`/" >/dev/null
24 | APP_HOME="`pwd -P`"
25 | cd "$SAVED" >/dev/null
26 |
27 | APP_NAME="Gradle"
28 | APP_BASE_NAME=`basename "$0"`
29 |
30 | # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
31 | DEFAULT_JVM_OPTS=""
32 |
33 | # Use the maximum available, or set MAX_FD != -1 to use that value.
34 | MAX_FD="maximum"
35 |
36 | warn ( ) {
37 | echo "$*"
38 | }
39 |
40 | die ( ) {
41 | echo
42 | echo "$*"
43 | echo
44 | exit 1
45 | }
46 |
47 | # OS specific support (must be 'true' or 'false').
48 | cygwin=false
49 | msys=false
50 | darwin=false
51 | nonstop=false
52 | case "`uname`" in
53 | CYGWIN* )
54 | cygwin=true
55 | ;;
56 | Darwin* )
57 | darwin=true
58 | ;;
59 | MINGW* )
60 | msys=true
61 | ;;
62 | NONSTOP* )
63 | nonstop=true
64 | ;;
65 | esac
66 |
67 | CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
68 |
69 | # Determine the Java command to use to start the JVM.
70 | if [ -n "$JAVA_HOME" ] ; then
71 | if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
72 | # IBM's JDK on AIX uses strange locations for the executables
73 | JAVACMD="$JAVA_HOME/jre/sh/java"
74 | else
75 | JAVACMD="$JAVA_HOME/bin/java"
76 | fi
77 | if [ ! -x "$JAVACMD" ] ; then
78 | die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
79 |
80 | Please set the JAVA_HOME variable in your environment to match the
81 | location of your Java installation."
82 | fi
83 | else
84 | JAVACMD="java"
85 | which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
86 |
87 | Please set the JAVA_HOME variable in your environment to match the
88 | location of your Java installation."
89 | fi
90 |
91 | # Increase the maximum file descriptors if we can.
92 | if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
93 | MAX_FD_LIMIT=`ulimit -H -n`
94 | if [ $? -eq 0 ] ; then
95 | if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
96 | MAX_FD="$MAX_FD_LIMIT"
97 | fi
98 | ulimit -n $MAX_FD
99 | if [ $? -ne 0 ] ; then
100 | warn "Could not set maximum file descriptor limit: $MAX_FD"
101 | fi
102 | else
103 | warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
104 | fi
105 | fi
106 |
107 | # For Darwin, add options to specify how the application appears in the dock
108 | if $darwin; then
109 | GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
110 | fi
111 |
112 | # For Cygwin, switch paths to Windows format before running java
113 | if $cygwin ; then
114 | APP_HOME=`cygpath --path --mixed "$APP_HOME"`
115 | CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
116 | JAVACMD=`cygpath --unix "$JAVACMD"`
117 |
118 | # We build the pattern for arguments to be converted via cygpath
119 | ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
120 | SEP=""
121 | for dir in $ROOTDIRSRAW ; do
122 | ROOTDIRS="$ROOTDIRS$SEP$dir"
123 | SEP="|"
124 | done
125 | OURCYGPATTERN="(^($ROOTDIRS))"
126 | # Add a user-defined pattern to the cygpath arguments
127 | if [ "$GRADLE_CYGPATTERN" != "" ] ; then
128 | OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
129 | fi
130 | # Now convert the arguments - kludge to limit ourselves to /bin/sh
131 | i=0
132 | for arg in "$@" ; do
133 | CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
134 | CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option
135 |
136 | if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition
137 | eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
138 | else
139 | eval `echo args$i`="\"$arg\""
140 | fi
141 | i=$((i+1))
142 | done
143 | case $i in
144 | (0) set -- ;;
145 | (1) set -- "$args0" ;;
146 | (2) set -- "$args0" "$args1" ;;
147 | (3) set -- "$args0" "$args1" "$args2" ;;
148 | (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
149 | (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
150 | (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
151 | (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
152 | (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
153 | (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
154 | esac
155 | fi
156 |
157 | # Split up the JVM_OPTS And GRADLE_OPTS values into an array, following the shell quoting and substitution rules
158 | function splitJvmOpts() {
159 | JVM_OPTS=("$@")
160 | }
161 | eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS
162 | JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME"
163 |
164 | exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"
165 |
--------------------------------------------------------------------------------
/demo-java-source/gradlew.bat:
--------------------------------------------------------------------------------
1 | @if "%DEBUG%" == "" @echo off
2 | @rem ##########################################################################
3 | @rem
4 | @rem Gradle startup script for Windows
5 | @rem
6 | @rem ##########################################################################
7 |
8 | @rem Set local scope for the variables with windows NT shell
9 | if "%OS%"=="Windows_NT" setlocal
10 |
11 | set DIRNAME=%~dp0
12 | if "%DIRNAME%" == "" set DIRNAME=.
13 | set APP_BASE_NAME=%~n0
14 | set APP_HOME=%DIRNAME%
15 |
16 | @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
17 | set DEFAULT_JVM_OPTS=
18 |
19 | @rem Find java.exe
20 | if defined JAVA_HOME goto findJavaFromJavaHome
21 |
22 | set JAVA_EXE=java.exe
23 | %JAVA_EXE% -version >NUL 2>&1
24 | if "%ERRORLEVEL%" == "0" goto init
25 |
26 | echo.
27 | echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
28 | echo.
29 | echo Please set the JAVA_HOME variable in your environment to match the
30 | echo location of your Java installation.
31 |
32 | goto fail
33 |
34 | :findJavaFromJavaHome
35 | set JAVA_HOME=%JAVA_HOME:"=%
36 | set JAVA_EXE=%JAVA_HOME%/bin/java.exe
37 |
38 | if exist "%JAVA_EXE%" goto init
39 |
40 | echo.
41 | echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
42 | echo.
43 | echo Please set the JAVA_HOME variable in your environment to match the
44 | echo location of your Java installation.
45 |
46 | goto fail
47 |
48 | :init
49 | @rem Get command-line arguments, handling Windows variants
50 |
51 | if not "%OS%" == "Windows_NT" goto win9xME_args
52 | if "%@eval[2+2]" == "4" goto 4NT_args
53 |
54 | :win9xME_args
55 | @rem Slurp the command line arguments.
56 | set CMD_LINE_ARGS=
57 | set _SKIP=2
58 |
59 | :win9xME_args_slurp
60 | if "x%~1" == "x" goto execute
61 |
62 | set CMD_LINE_ARGS=%*
63 | goto execute
64 |
65 | :4NT_args
66 | @rem Get arguments from the 4NT Shell from JP Software
67 | set CMD_LINE_ARGS=%$
68 |
69 | :execute
70 | @rem Setup the command line
71 |
72 | set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
73 |
74 | @rem Execute Gradle
75 | "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
76 |
77 | :end
78 | @rem End local scope for the variables with windows NT shell
79 | if "%ERRORLEVEL%"=="0" goto mainEnd
80 |
81 | :fail
82 | rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
83 | rem the _cmd.exe /c_ return code!
84 | if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
85 | exit /b 1
86 |
87 | :mainEnd
88 | if "%OS%"=="Windows_NT" endlocal
89 |
90 | :omega
91 |
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/demo-java-source/src/main/java/com/example/MessageDto.java:
--------------------------------------------------------------------------------
1 | package com.example;
2 |
3 | class MessageDto {
4 |
5 |
6 | String name;
7 |
8 | public String getName() {
9 | return name;
10 | }
11 |
12 | public void setName(String name) {
13 | this.name = name;
14 | }
15 | }
--------------------------------------------------------------------------------
/demo-java-source/src/main/java/com/example/SampleSource.java:
--------------------------------------------------------------------------------
1 | package com.example;
2 |
3 | import org.springframework.beans.factory.annotation.Autowired;
4 | import org.springframework.cloud.stream.annotation.EnableBinding;
5 | import org.springframework.cloud.stream.messaging.Source;
6 | import org.springframework.http.MediaType;
7 | import org.springframework.messaging.MessageChannel;
8 | import org.springframework.messaging.support.GenericMessage;
9 | import org.springframework.web.bind.annotation.PostMapping;
10 | import org.springframework.web.bind.annotation.RequestBody;
11 | import org.springframework.web.bind.annotation.ResponseBody;
12 | import org.springframework.web.bind.annotation.RestController;
13 |
14 | import com.fasterxml.jackson.core.JsonProcessingException;
15 | import com.fasterxml.jackson.databind.ObjectMapper;
16 |
17 | @RestController
18 | @EnableBinding(Source.class)
19 | public class SampleSource {
20 |
21 | private final MessageChannel output;
22 |
23 | @Autowired
24 | public SampleSource(MessageChannel output) {
25 | this.output = output;
26 | }
27 |
28 | private ObjectMapper objectMapper = new ObjectMapper();
29 |
30 | @PostMapping(path = "/message", consumes = MediaType.APPLICATION_JSON_UTF8_VALUE)
31 | public @ResponseBody void sendMessage(@RequestBody MessageDto message) throws JsonProcessingException {
32 | byte[] bytes = objectMapper.writeValueAsBytes(message);
33 |
34 | // normally you can use something like this instead of bytes :
35 | // MessageBuilder.withPayload(name).build()
36 | output.send(new GenericMessage<>(bytes));
37 | }
38 | }
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/demo-java-source/src/main/java/com/example/StreamApplication.java:
--------------------------------------------------------------------------------
1 | package com.example;
2 |
3 | import org.springframework.boot.SpringApplication;
4 | import org.springframework.boot.autoconfigure.SpringBootApplication;
5 | import org.springframework.cloud.stream.annotation.EnableBinding;
6 | import org.springframework.cloud.stream.messaging.Source;
7 |
8 | @SpringBootApplication
9 | @EnableBinding(Source.class)
10 | public class StreamApplication {
11 |
12 | public static void main(String[] args) {
13 | SpringApplication.run(StreamApplication.class, args);
14 | }
15 |
16 | }
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/demo-java-source/src/main/resources/application.properties:
--------------------------------------------------------------------------------
1 | spring.cloud.stream.bindings.output.destination=messages
2 | #spring.cloud.stream.bindings.output.content-type=application/json
3 |
4 | # for integrating with non spring apps
5 | spring.cloud.stream.bindings.output.producer.headerMode=raw
6 | spring.cloud.stream.kafka.binder.zkNodes=localhost
7 | spring.cloud.stream.kafka.binder.brokers=localhost
8 |
9 | server.port=8080
--------------------------------------------------------------------------------
/demo-java-source/src/test/java/com/example/DemoApplicationTests.java:
--------------------------------------------------------------------------------
1 | package com.example;
2 |
3 | import org.junit.Test;
4 | import org.junit.runner.RunWith;
5 | import org.springframework.boot.test.context.SpringBootTest;
6 | import org.springframework.test.context.junit4.SpringRunner;
7 |
8 | @RunWith(SpringRunner.class)
9 | @SpringBootTest
10 | public class DemoApplicationTests {
11 |
12 | @Test
13 | public void contextLoads() {
14 | }
15 |
16 | }
17 |
--------------------------------------------------------------------------------
/demo-kotlin-sink/build.gradle:
--------------------------------------------------------------------------------
1 | buildscript {
2 | ext.kotlin_version = '1.0.6'
3 | ext {
4 | springBootVersion = '1.4.3.RELEASE'
5 | }
6 | repositories {
7 | mavenCentral()
8 | }
9 | dependencies {
10 | classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
11 | classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
12 | }
13 | }
14 |
15 | apply plugin: 'java'
16 | apply plugin: 'kotlin'
17 | apply plugin: 'eclipse'
18 | apply plugin: 'org.springframework.boot'
19 |
20 | jar {
21 | baseName = 'demo-kotlin-sink'
22 | version = '0.0.1-SNAPSHOT'
23 | }
24 |
25 | sourceCompatibility = 1.8
26 |
27 | repositories {
28 | mavenCentral()
29 | }
30 |
31 |
32 |
33 |
34 | dependencies {
35 | compile('org.springframework.cloud:spring-cloud-starter-stream-kafka')
36 | compile("com.fasterxml.jackson.module:jackson-module-kotlin:2.8.4")
37 | testCompile('org.springframework.boot:spring-boot-starter-test')
38 | compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
39 | }
40 |
41 | dependencyManagement {
42 | imports {
43 | mavenBom "org.springframework.cloud:spring-cloud-dependencies:Camden.SR3"
44 | }
45 | }
46 | sourceSets {
47 | main.java.srcDirs += 'src/main/kotlin'
48 | }
49 |
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/demo-kotlin-sink/gradle/wrapper/gradle-wrapper.jar:
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https://raw.githubusercontent.com/kgoralski/go-kotlin-java-kafka/342ba9d8ddea7cece2b9f155fca9522327c2fe68/demo-kotlin-sink/gradle/wrapper/gradle-wrapper.jar
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/demo-kotlin-sink/gradle/wrapper/gradle-wrapper.properties:
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1 | #Sat Jan 07 17:05:33 CET 2017
2 | distributionBase=GRADLE_USER_HOME
3 | distributionPath=wrapper/dists
4 | zipStoreBase=GRADLE_USER_HOME
5 | zipStorePath=wrapper/dists
6 | distributionUrl=https\://services.gradle.org/distributions/gradle-3.1-bin.zip
7 |
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/demo-kotlin-sink/gradlew:
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1 | #!/usr/bin/env bash
2 |
3 | ##############################################################################
4 | ##
5 | ## Gradle start up script for UN*X
6 | ##
7 | ##############################################################################
8 |
9 | # Attempt to set APP_HOME
10 | # Resolve links: $0 may be a link
11 | PRG="$0"
12 | # Need this for relative symlinks.
13 | while [ -h "$PRG" ] ; do
14 | ls=`ls -ld "$PRG"`
15 | link=`expr "$ls" : '.*-> \(.*\)$'`
16 | if expr "$link" : '/.*' > /dev/null; then
17 | PRG="$link"
18 | else
19 | PRG=`dirname "$PRG"`"/$link"
20 | fi
21 | done
22 | SAVED="`pwd`"
23 | cd "`dirname \"$PRG\"`/" >/dev/null
24 | APP_HOME="`pwd -P`"
25 | cd "$SAVED" >/dev/null
26 |
27 | APP_NAME="Gradle"
28 | APP_BASE_NAME=`basename "$0"`
29 |
30 | # Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
31 | DEFAULT_JVM_OPTS=""
32 |
33 | # Use the maximum available, or set MAX_FD != -1 to use that value.
34 | MAX_FD="maximum"
35 |
36 | warn ( ) {
37 | echo "$*"
38 | }
39 |
40 | die ( ) {
41 | echo
42 | echo "$*"
43 | echo
44 | exit 1
45 | }
46 |
47 | # OS specific support (must be 'true' or 'false').
48 | cygwin=false
49 | msys=false
50 | darwin=false
51 | nonstop=false
52 | case "`uname`" in
53 | CYGWIN* )
54 | cygwin=true
55 | ;;
56 | Darwin* )
57 | darwin=true
58 | ;;
59 | MINGW* )
60 | msys=true
61 | ;;
62 | NONSTOP* )
63 | nonstop=true
64 | ;;
65 | esac
66 |
67 | CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
68 |
69 | # Determine the Java command to use to start the JVM.
70 | if [ -n "$JAVA_HOME" ] ; then
71 | if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
72 | # IBM's JDK on AIX uses strange locations for the executables
73 | JAVACMD="$JAVA_HOME/jre/sh/java"
74 | else
75 | JAVACMD="$JAVA_HOME/bin/java"
76 | fi
77 | if [ ! -x "$JAVACMD" ] ; then
78 | die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
79 |
80 | Please set the JAVA_HOME variable in your environment to match the
81 | location of your Java installation."
82 | fi
83 | else
84 | JAVACMD="java"
85 | which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
86 |
87 | Please set the JAVA_HOME variable in your environment to match the
88 | location of your Java installation."
89 | fi
90 |
91 | # Increase the maximum file descriptors if we can.
92 | if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
93 | MAX_FD_LIMIT=`ulimit -H -n`
94 | if [ $? -eq 0 ] ; then
95 | if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
96 | MAX_FD="$MAX_FD_LIMIT"
97 | fi
98 | ulimit -n $MAX_FD
99 | if [ $? -ne 0 ] ; then
100 | warn "Could not set maximum file descriptor limit: $MAX_FD"
101 | fi
102 | else
103 | warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
104 | fi
105 | fi
106 |
107 | # For Darwin, add options to specify how the application appears in the dock
108 | if $darwin; then
109 | GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
110 | fi
111 |
112 | # For Cygwin, switch paths to Windows format before running java
113 | if $cygwin ; then
114 | APP_HOME=`cygpath --path --mixed "$APP_HOME"`
115 | CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
116 | JAVACMD=`cygpath --unix "$JAVACMD"`
117 |
118 | # We build the pattern for arguments to be converted via cygpath
119 | ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
120 | SEP=""
121 | for dir in $ROOTDIRSRAW ; do
122 | ROOTDIRS="$ROOTDIRS$SEP$dir"
123 | SEP="|"
124 | done
125 | OURCYGPATTERN="(^($ROOTDIRS))"
126 | # Add a user-defined pattern to the cygpath arguments
127 | if [ "$GRADLE_CYGPATTERN" != "" ] ; then
128 | OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
129 | fi
130 | # Now convert the arguments - kludge to limit ourselves to /bin/sh
131 | i=0
132 | for arg in "$@" ; do
133 | CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
134 | CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option
135 |
136 | if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition
137 | eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
138 | else
139 | eval `echo args$i`="\"$arg\""
140 | fi
141 | i=$((i+1))
142 | done
143 | case $i in
144 | (0) set -- ;;
145 | (1) set -- "$args0" ;;
146 | (2) set -- "$args0" "$args1" ;;
147 | (3) set -- "$args0" "$args1" "$args2" ;;
148 | (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
149 | (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
150 | (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
151 | (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
152 | (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
153 | (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
154 | esac
155 | fi
156 |
157 | # Split up the JVM_OPTS And GRADLE_OPTS values into an array, following the shell quoting and substitution rules
158 | function splitJvmOpts() {
159 | JVM_OPTS=("$@")
160 | }
161 | eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS
162 | JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME"
163 |
164 | # by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
165 | if [[ "$(uname)" == "Darwin" ]] && [[ "$HOME" == "$PWD" ]]; then
166 | cd "$(dirname "$0")"
167 | fi
168 |
169 | exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"
170 |
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/demo-kotlin-sink/gradlew.bat:
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1 | @if "%DEBUG%" == "" @echo off
2 | @rem ##########################################################################
3 | @rem
4 | @rem Gradle startup script for Windows
5 | @rem
6 | @rem ##########################################################################
7 |
8 | @rem Set local scope for the variables with windows NT shell
9 | if "%OS%"=="Windows_NT" setlocal
10 |
11 | set DIRNAME=%~dp0
12 | if "%DIRNAME%" == "" set DIRNAME=.
13 | set APP_BASE_NAME=%~n0
14 | set APP_HOME=%DIRNAME%
15 |
16 | @rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
17 | set DEFAULT_JVM_OPTS=
18 |
19 | @rem Find java.exe
20 | if defined JAVA_HOME goto findJavaFromJavaHome
21 |
22 | set JAVA_EXE=java.exe
23 | %JAVA_EXE% -version >NUL 2>&1
24 | if "%ERRORLEVEL%" == "0" goto init
25 |
26 | echo.
27 | echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
28 | echo.
29 | echo Please set the JAVA_HOME variable in your environment to match the
30 | echo location of your Java installation.
31 |
32 | goto fail
33 |
34 | :findJavaFromJavaHome
35 | set JAVA_HOME=%JAVA_HOME:"=%
36 | set JAVA_EXE=%JAVA_HOME%/bin/java.exe
37 |
38 | if exist "%JAVA_EXE%" goto init
39 |
40 | echo.
41 | echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
42 | echo.
43 | echo Please set the JAVA_HOME variable in your environment to match the
44 | echo location of your Java installation.
45 |
46 | goto fail
47 |
48 | :init
49 | @rem Get command-line arguments, handling Windows variants
50 |
51 | if not "%OS%" == "Windows_NT" goto win9xME_args
52 |
53 | :win9xME_args
54 | @rem Slurp the command line arguments.
55 | set CMD_LINE_ARGS=
56 | set _SKIP=2
57 |
58 | :win9xME_args_slurp
59 | if "x%~1" == "x" goto execute
60 |
61 | set CMD_LINE_ARGS=%*
62 |
63 | :execute
64 | @rem Setup the command line
65 |
66 | set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
67 |
68 | @rem Execute Gradle
69 | "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
70 |
71 | :end
72 | @rem End local scope for the variables with windows NT shell
73 | if "%ERRORLEVEL%"=="0" goto mainEnd
74 |
75 | :fail
76 | rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
77 | rem the _cmd.exe /c_ return code!
78 | if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
79 | exit /b 1
80 |
81 | :mainEnd
82 | if "%OS%"=="Windows_NT" endlocal
83 |
84 | :omega
85 |
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/demo-kotlin-sink/settings.gradle:
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1 | rootProject.name = 'demo-kotlin-sink'
2 |
3 |
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/demo-kotlin-sink/src/main/kotlin/com/example/SampleSink.kt:
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1 | package com.example
2 |
3 | import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
4 | import org.slf4j.LoggerFactory
5 | import org.springframework.cloud.stream.annotation.EnableBinding
6 | import org.springframework.cloud.stream.annotation.StreamListener
7 | import org.springframework.cloud.stream.messaging.Sink
8 | import org.springframework.stereotype.Component
9 |
10 | @Component
11 | @EnableBinding(Sink::class)
12 | open class SampleSink {
13 |
14 | // jackson kotlin module
15 | val JSON = jacksonObjectMapper()
16 |
17 | data class Message(var name: String)
18 |
19 | private val logger = LoggerFactory.getLogger(SampleSink::class.java)
20 | @StreamListener(Sink.INPUT)
21 | fun receive(message: ByteArray) {
22 | val parsedMessage = JSON.readValue(message, Message::class.java)
23 | logger.info("Kotlin received: " + parsedMessage.name)
24 | }
25 | }
26 |
27 |
28 |
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/demo-kotlin-sink/src/main/kotlin/com/example/SinkApplication.kt:
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1 | package com.example
2 |
3 |
4 | import org.springframework.boot.SpringApplication
5 | import org.springframework.boot.autoconfigure.SpringBootApplication
6 |
7 | @SpringBootApplication
8 | open class SinkApplication {
9 |
10 |
11 | companion object {
12 |
13 | @JvmStatic fun main(args: Array) {
14 | SpringApplication.run(SinkApplication::class.java, *args)
15 | }
16 | }
17 |
18 | }
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/demo-kotlin-sink/src/main/resources/application.properties:
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1 | spring.cloud.stream.bindings.input.destination=messages
2 | #spring.cloud.stream.bindings.input.content-type=application/json
3 |
4 | # for integrating with non spring apps
5 | spring.cloud.stream.bindings.input.consumer.headerMode=raw
6 | spring.cloud.stream.bindings.input.group=messageGroup
7 | spring.cloud.stream.kafka.bindings.input.consumer.resetOffsets=true
8 | spring.cloud.stream.kafka.binder.zkNodes=localhost
9 | spring.cloud.stream.kafka.binder.brokers=localhost
10 |
11 | server.port=8081
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