├── config └── config.jsonSAMPLE ├── .gitattributes ├── package.json ├── .gitignore ├── example.js ├── readme.md ├── client.js └── LICENSE /config/config.jsonSAMPLE: -------------------------------------------------------------------------------- 1 | { 2 | "EventHubsNamespace": "", 3 | "EventHubsHubName": "", 4 | "DeviceName": "", 5 | "EventHubsKeyName": "", 6 | "EventHubsKey": "" 7 | } -------------------------------------------------------------------------------- /.gitattributes: -------------------------------------------------------------------------------- 1 | # Auto detect text files and perform LF normalization 2 | * text=auto 3 | 4 | # Custom for Visual Studio 5 | *.cs diff=csharp 6 | *.sln merge=union 7 | *.csproj merge=union 8 | *.vbproj merge=union 9 | *.fsproj merge=union 10 | *.dbproj merge=union 11 | 12 | # Standard to msysgit 13 | *.doc diff=astextplain 14 | *.DOC diff=astextplain 15 | *.docx diff=astextplain 16 | *.DOCX diff=astextplain 17 | *.dot diff=astextplain 18 | *.DOT diff=astextplain 19 | *.pdf diff=astextplain 20 | *.PDF diff=astextplain 21 | *.rtf diff=astextplain 22 | *.RTF diff=astextplain 23 | -------------------------------------------------------------------------------- /package.json: -------------------------------------------------------------------------------- 1 | { 2 | "name": "eventhubs-js", 3 | "version": "1.1.3", 4 | "description": "Easy to use client for Azure event hubs", 5 | "main": "client.js", 6 | "repository": { 7 | "type": "git", 8 | "url": "https://github.com/ytechie/eventhubs-js" 9 | }, 10 | "scripts": { 11 | "test": "echo \"Error: no test specified\" && exit 1" 12 | }, 13 | "author": "Jason Young ", 14 | "license": "Apache2", 15 | "keywords": [ 16 | "event", 17 | "hubs", 18 | "azure", 19 | "service", 20 | "bus", 21 | "mqtt" 22 | ], 23 | "dependencies": { 24 | "moment": "^2.8.4", 25 | "q": "^1.1.2" 26 | }, 27 | "devDependencies": { 28 | "easy-config": "^0.4.3" 29 | } 30 | } 31 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | # Windows image file caches 2 | Thumbs.db 3 | ehthumbs.db 4 | 5 | # Folder config file 6 | Desktop.ini 7 | 8 | # Recycle Bin used on file shares 9 | $RECYCLE.BIN/ 10 | 11 | # Windows Installer files 12 | *.cab 13 | *.msi 14 | *.msm 15 | *.msp 16 | 17 | # ========================= 18 | # Operating System Files 19 | # ========================= 20 | 21 | # OSX 22 | # ========================= 23 | 24 | .DS_Store 25 | .AppleDouble 26 | .LSOverride 27 | 28 | # Icon must end with two \r 29 | Icon 30 | 31 | 32 | # Thumbnails 33 | ._* 34 | 35 | # Files that might appear on external disk 36 | .Spotlight-V100 37 | .Trashes 38 | 39 | # Directories potentially created on remote AFP share 40 | .AppleDB 41 | .AppleDesktop 42 | Network Trash Folder 43 | Temporary Items 44 | .apdisk 45 | 46 | node_modules 47 | config/config.json 48 | .ntvs_analysis.dat 49 | bin/* 50 | obj/* 51 | *.suo 52 | npm-debug.log 53 | 54 | # ignore visual studio related project files 55 | *.njsproj 56 | *.sln 57 | 58 | test.js 59 | 60 | # intellij project file 61 | .idea -------------------------------------------------------------------------------- /example.js: -------------------------------------------------------------------------------- 1 | var Q = require("q"); 2 | var easyConfig = require('easy-config'); 3 | var eventHubs = require('./client.js'); 4 | 5 | // Full Event Hub publisher URI 6 | var config; 7 | var eventHubsUri; 8 | var sasToken; 9 | 10 | var config = easyConfig.loadConfig(); 11 | 12 | if (!config.EventHubsNamespace) { 13 | throw new Error("Config file not found, or you forgot to set the namespace in the config."); 14 | } 15 | 16 | var eventHubsNamespace = config.EventHubsNamespace, 17 | eventHubsHubName = config.EventHubsHubName, 18 | eventHubsKeyName = config.EventHubsKeyName, 19 | eventHubsKey = config.EventHubsKey, 20 | sasToken = config.SasToken, 21 | deviceId = config.DeviceName; 22 | 23 | testSendContinuous(); 24 | //testSendPerformance(); 25 | //example1(); 26 | //exampleWithSasToken(); 27 | 28 | function sendRandomData(silent) { 29 | var deferral = Q.defer(); 30 | 31 | var payload = { 32 | Temperature: (Math.random() * 100) + 1, 33 | Humidity: Math.random() 34 | } 35 | 36 | eventHubs.sendMessage({ 37 | message: payload, 38 | deviceId: deviceId, 39 | }).then(function () { 40 | if (!silent) console.log('Sent ' + JSON.stringify(payload)); 41 | deferral.resolve(); 42 | }).catch(function (error) { 43 | if (!silent) console.log('Error sending message: ' + error); 44 | deferral.reject(error); 45 | }) 46 | .done(); 47 | 48 | return deferral.promise; 49 | } 50 | 51 | function testSendContinuous() { 52 | eventHubs.init({ 53 | hubNamespace: eventHubsNamespace, 54 | hubName: eventHubsHubName, 55 | keyName: eventHubsKeyName, 56 | key: eventHubsKey 57 | }); 58 | 59 | 60 | } 61 | 62 | function testSendPerformance() { 63 | eventHubs.init({ 64 | hubNamespace: eventHubsNamespace, 65 | hubName: eventHubsHubName, 66 | keyName: eventHubsKeyName, 67 | key: eventHubsKey 68 | }); 69 | 70 | //warm-up 71 | sendRandomData(true); 72 | sendRandomData(true); 73 | sendRandomData(true); 74 | sendRandomData(true); 75 | sendRandomData(true); 76 | 77 | var i, 78 | start = new Date(), 79 | end, 80 | promise, 81 | promises = [], 82 | iterations = 1000; 83 | 84 | for (i = 0; i < iterations; i++) { 85 | promise = sendRandomData(true); 86 | promises.push(promise); 87 | } 88 | Q.allSettled(promises).then(function () { 89 | end = new Date(); 90 | var elapsed = end.getTime() - start.getTime(); 91 | console.log('Test Complete. Took ' + elapsed + 'ms to send ' + iterations + 'messages'); 92 | console.log(elapsed / iterations + 'ms / message'); 93 | console.log(1000 / (elapsed / iterations) + ' messages / second'); 94 | }); 95 | } 96 | 97 | function example1() { 98 | eventHubs.init({ 99 | hubNamespace: eventHubsNamespace, 100 | hubName: eventHubsHubName, 101 | keyName: eventHubsKeyName, 102 | key: eventHubsKey 103 | }); 104 | 105 | var deviceMessage = { 106 | Temperature: 45.2, 107 | Pressure: 23.7 108 | } 109 | 110 | eventHubs.sendMessage({ 111 | message: deviceMessage, 112 | deviceId: 1, 113 | }); 114 | } 115 | 116 | function exampleWithSasToken() { 117 | eventHubs.init({ 118 | hubNamespace: eventHubsNamespace, 119 | hubName: eventHubsHubName, 120 | sasToken: sasToken 121 | }); 122 | 123 | var deviceMessage = { 124 | Temperature: 45.2, 125 | Pressure: 23.7 126 | } 127 | 128 | eventHubs.sendMessage({ 129 | message: deviceMessage, 130 | deviceId: 1, 131 | }); 132 | } -------------------------------------------------------------------------------- /readme.md: -------------------------------------------------------------------------------- 1 | An Azure Event Hub client that is easy to use and performs well. From a local machine, I'm able to sustain **~300** *single* messages per second from a single client. When running in an Azure VM in the same region as the Event Hubs instance, I was able to send **~400** *single* messages per second. From a Raspberry PI, I was able to send **~40** *single* messages per second. 2 | There is an option for batching messages if needed by using the `sendMessages` function. 3 | 4 | ### Easy Dev Usage 5 | 6 | eventHubs.init({ 7 | hubNamespace: eventHubsNamespace, 8 | hubName: eventHubsHubName, 9 | keyName: eventHubsKeyName, 10 | key: eventHubsKey 11 | }); 12 | 13 | var deviceMessage = { 14 | Temperature: 45.2, 15 | Pressure: 23.7 16 | } 17 | 18 | eventHubs.sendMessage({ 19 | message: deviceMessage, 20 | deviceId: 1, 21 | }); 22 | 23 | Note: deviceId is simply a unique name to identify your device to Azure. If not given, you will recieve a 401 Authorization failed response. 24 | 25 | ### Production Usages 26 | 27 | When you initialize the event hubs client, it's advisable to use a SAS token in a production environment. This is a revokable key that is unique to the device. You can generate a token programatically, or [online using this form](http://eventhubssasgenerator.azurewebsites.net/). 28 | 29 | eventHubs.init({ 30 | hubNamespace: eventHubsNamespace, 31 | hubName: eventHubsHubName, 32 | sasToken: sasToken 33 | }); 34 | 35 | For batching multiple messages and sending them together in single REST call, use the `sendMessages` function: 36 | 37 | eventHubs.sendMessages({ 38 | messages: [], // array of messages 39 | deviceId: 1, 40 | }); 41 | 42 | Beware that Azure EventHub REST API has a limit of 256kb for batching (per call), so make sure you batched messages 43 | do not reach this limit (otherwise an error will be returned). 44 | 45 | ### Installation 46 | 47 | npm install eventhubs-js 48 | 49 | Don't forget to update your `package.json` file. 50 | 51 | ### Performance Optimizations 52 | 53 | Performance was optimized in a number of ways: 54 | 55 | 1. Setting `http.globalAgent.maxSockets = 50;` increases the HTTP connection pool, which allows us to create more connections to serve messages that need sent. If you don't send a large volume of messages, no problem, the pool will remain relatively empty. 56 | 2. Caching the SAS Tokens. I haven't tested the performance of the node.js crypto libraries and moment time calculations, but it was easy enough to cache the generated SAS tokens to avoid recalcuating on each message. 57 | 3. Automatic recreation of cached token just before it expires 58 | 59 | ### Examples & Promises 60 | 61 | Promises allow you to chain calls without "callback hell": 62 | 63 | eventHubs.sendMessage({ 64 | message: deviceMessage, 65 | deviceId: 1, 66 | }).then(function() { 67 | console.log('Message Sent!'); 68 | }); 69 | 70 | Promises also allow us to kick of multiple send requests simultaneously, and easily manage the results: 71 | 72 | var promise, promises; 73 | 74 | for (i = 0; i < iterations; i++) { 75 | promise = eventHubs.sendMessage({ 76 | message: deviceMessage, 77 | deviceId: 1, 78 | }); 79 | 80 | promises.push(promise); 81 | } 82 | Q.allSettled(promises).then(function () { 83 | console.log('All Messages Sent!'); 84 | }); 85 | 86 | ### Alternative Clients 87 | 88 | * [https://git.allseenalliance.org/cgit/core/alljoyn-js.git/tree/](https://git.allseenalliance.org/cgit/core/alljoyn-js.git/tree/) 89 | * [https://github.com/noodlefrenzy/event-hub-client](https://github.com/noodlefrenzy/event-hub-client) 90 | 91 | # License 92 | 93 | Microsoft Developer Experience & Evangelism 94 | 95 | Copyright (c) Microsoft Corporation. All rights reserved. 96 | 97 | THIS CODE AND INFORMATION ARE PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE. 98 | 99 | The example companies, organizations, products, domain names, e-mail addresses, logos, people, places, and events depicted herein are fictitious. No association with any real company, organization, product, domain name, email address, logo, person, places, or events is intended or should be inferred. 100 | -------------------------------------------------------------------------------- /client.js: -------------------------------------------------------------------------------- 1 | var Q = require("q"), 2 | http = require('https'), 3 | https = require('https'), 4 | crypto = require('crypto'), 5 | moment = require('moment'); 6 | 7 | var namespace, 8 | hubName, 9 | keyName, 10 | key, 11 | sasToken, 12 | sasTokens = {}; //key=uri, value=SAS token 13 | 14 | function getSasToken(uri) { 15 | if(sasToken) { 16 | return sasToken; 17 | } 18 | 19 | var expiration, 20 | toSign, 21 | hmac, 22 | encodedHmac, 23 | token; 24 | 25 | //Cache tokens to avoid recalculations 26 | token = sasTokens[uri]; 27 | 28 | // remove expired tokens from the cache 29 | if(token && moment().unix() < token.expiration) { 30 | return token.token; 31 | } 32 | 33 | expiration = moment().add(15, 'days').unix(); 34 | 35 | toSign = encodeURIComponent(uri) + '\n' + expiration; 36 | hmac = crypto.createHmac('sha256', key); 37 | hmac.update(toSign); 38 | encodedHmac = hmac.digest('base64'); 39 | 40 | token = 'SharedAccessSignature sr=' + encodeURIComponent(uri) + '&sig=' + encodeURIComponent(encodedHmac) + '&se=' + expiration + '&skn=' + keyName; 41 | 42 | sasTokens[uri] = { 43 | token: token, 44 | expiration: expiration 45 | }; 46 | 47 | console.log('Generated SAS token "' + token + '"'); 48 | 49 | return token; 50 | } 51 | 52 | //https://msdn.microsoft.com/en-us/library/azure/dn790664.aspx 53 | function getDeviceUri(deviceId) { 54 | var uri = null; 55 | if (!deviceId) { 56 | uri = 'https://' + namespace 57 | + '.servicebus.windows.net' + '/' + hubName + '/messages'; 58 | } else { 59 | uri = 'https://' + namespace 60 | + '.servicebus.windows.net' + '/' + hubName 61 | + '/publishers/' + encodeURIComponent(deviceId) + '/messages'; 62 | } 63 | return uri; 64 | } 65 | 66 | //hubNamespace, hubName, keyName, key 67 | function init(options) { 68 | namespace = options.hubNamespace; 69 | hubName = options.hubName; 70 | keyName = options.keyName; 71 | key = options.key; 72 | sasToken = options.sasToken; 73 | 74 | //Allow the connection pool to grow larger. This improves performance 75 | //by a factor of 10x in my testing 76 | http.globalAgent.maxSockets = 50; 77 | } 78 | 79 | function sendMessage(messageObject) { 80 | var message = messageObject.message, 81 | deviceId = messageObject.deviceId, 82 | payload; 83 | 84 | if (typeof message === 'string') { 85 | payload = message; 86 | } else { 87 | //This allows us to send in a POJSO 88 | payload = JSON.stringify(message); 89 | } 90 | 91 | return send(payload, deviceId); 92 | } 93 | 94 | function sendMessages(messageObject) { 95 | var messages = messageObject.messages, 96 | deviceId = messageObject.deviceId, 97 | payload; 98 | 99 | if (messages.length === 0) 100 | throw new Error("Given argument contains no messages!"); 101 | 102 | payload = JSON.stringify(messages); 103 | 104 | return send(payload, deviceId); 105 | } 106 | 107 | function send(payload, deviceId) { 108 | var deferral, 109 | requestOptions, 110 | deviceUri, 111 | token, 112 | req, 113 | responseData = ''; 114 | 115 | deferral = Q.defer(); 116 | 117 | deviceUri = getDeviceUri(deviceId); 118 | token = getSasToken(deviceUri); 119 | 120 | requestOptions = { 121 | hostname: namespace + '.servicebus.windows.net', 122 | port: 443, 123 | path: deviceId ? '/' + hubName + '/publishers/' + deviceId + '/messages' : '/' + hubName + '/messages', 124 | method: 'POST', 125 | headers: { 126 | 'Authorization': token, 127 | 'Content-Length': Buffer.byteLength(payload), 128 | 'Content-Type': 'application/atom+xml;type=entry;charset=utf-8' 129 | } 130 | } 131 | 132 | req = https.request(requestOptions, function (res) { 133 | res.on('data', function (data) { 134 | responseData += data; 135 | }).on('end', function () { 136 | if (res.statusCode !== 201) { 137 | deferral.reject(new Error("Invalid server status: " + res.statusCode + "Message: " + responseData)); 138 | return; 139 | } 140 | 141 | deferral.resolve({ 142 | statusCode: res.statusCode, 143 | responseData: responseData 144 | }); 145 | }).on('error', function (e) { 146 | deferral.reject(e); 147 | }); 148 | }); 149 | 150 | req.on('error', function(e){ 151 | deferral.reject(e); 152 | }); 153 | 154 | req.setSocketKeepAlive(true); 155 | req.write(payload); 156 | req.end(); 157 | 158 | return deferral.promise; 159 | } 160 | 161 | exports.init = init; 162 | exports.sendMessage = sendMessage; 163 | exports.sendMessages = sendMessages; 164 | -------------------------------------------------------------------------------- /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. 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