如何使用AWS IoT向Web浏览器发送消息/从Web浏览器接收消息

问题描述

我们正在尝试使用Amazon Web Services物联网（AWS IoT）从Web浏览器发送消息到Web浏览器（例如：）。鉴于AWS IoT支持JavaScript，我们期望 可能 ...

我们在AWS IoT文档中进行了搜索，但仅找到了服务器端示例 （公开AWS秘密/密钥...）

是否有任何有效的工作使用AWS IoT在浏览器中通过WebSockets / MQTT发送/接收消息的示例或教程（例如：使用AWS Cognito进行身份验证）？谢谢！

解决方案

下面是一个示例，该示例使用JS中的认知身份池来连接，发布和响应订阅。 > //配置Cognito身份池
AWS.config.region ='us-east-1';
var凭证=新的AWS.CognitoIdentityCredentials（{
IdentityPoolId： 'us-east-1：您的身份池GUID'，
}）；

//获取来自Cognito的AWS凭证是异步的，因此我们需要在回调
凭证中驱动其余mqtt客户端初始化.get（function（err）{
if（err）{
console）。 log（err）;
的回报；
}
var requestUrl = SigV4Utils.getSignedUrl（'wss'，'data.iot.us-east-1.amazonaws.com'，'/ mqtt'，
'iotdevicegateway'，' us-east-1'，
凭据.accessKeyId，凭据.secretAccessKey，凭据.sessionToken）;
initClient（requestUrl）;
}）；

函数init（）{
//做设置东西
}

//连接客户端，订阅绘图主题，然后发布一个嘿，我已连接消息
函数initClient（requestUrl）{
var clientId = String（Math.random（））。replace（'。'，））;
var client = new Paho.MQTT.Client（requestUrl，clientId）;
var connectOptions = {
onSuccess：function（）{
console.log（’connected’）;

//订阅图形
client.subscribe（ your / mqtt / topic）;

//发布生命周期事件
message = new Paho.MQTT.Message（’{ id：’+凭据.identityId +’}}））;
message.destinationName =‘您的/ mqtt /主题’；
console.log（message）;
client.send（message）;
}，
useSSL：true，
timeout：3，
mqttVersion：4，
onFailure：function（）{
console.error（'connect失败'）;
}
};
client.connect（connectOptions）;

client.onMessageArrived =函数（消息）{

try {
console.log（ msg到达： + message.payloadString）;
} catch（e）{
console.log（ error！ + e）;
}

};
}


请记住还要授权您的IAM角色进行订阅/发布。以下是示例：

  {
 Version： 2012-10-17，
声明：[
 {
效果：允许，
操作：[
 iot：Connect 
]，
资源： * 
}，
 {
效果：允许，
操作： iot：Receive，
资源 ： * 
}，
 {
 Effect：允许，
 Action： iot：Subscribe，
 Resource：[ 
 arn：aws：iot：us-east-1 :: your / mqtt / topic 
] 
}，
 {
 Effect：允许，
动作： iot：Publish，
资源：[
 arn：aws：iot：us-east-1 :: your / mqtt / topic 
] 
} 
] 
} 
  

We are trying to use Amazon Web Services Internet of Things (AWS IoT) to send messages from/to a Web Browser (e.g: . Given that the AWS IoT supports JavaScript we expect that this is possible ...

We have searched at the AWS IoT Documentation but only found server-side examples (which expose AWS secrets/keys...)

Are there any good working examples or tutorials for using AWS IoT to send/receive messages via WebSockets/MQTT in the browser (e.g: authenticating with AWS Cognito)? Thanks!

解决方案

Here's a sample that uses a cognito identity pool in JS to connect, publish and react to a subscription.

// Configure Cognito identity pool
AWS.config.region = 'us-east-1';
var credentials = new AWS.CognitoIdentityCredentials({
    IdentityPoolId: 'us-east-1:your identity pool guid',
});

// Getting AWS creds from Cognito is async, so we need to drive the rest of the mqtt client initialization in a callback
credentials.get(function(err) {
    if(err) {
        console.log(err);
        return;
    }
    var requestUrl = SigV4Utils.getSignedUrl('wss', 'data.iot.us-east-1.amazonaws.com', '/mqtt',
        'iotdevicegateway', 'us-east-1',
        credentials.accessKeyId, credentials.secretAccessKey, credentials.sessionToken);
    initClient(requestUrl);
});

function init() {
  // do setup stuff
}

// Connect the client, subscribe to the drawing topic, and publish a "hey I connected" message
function initClient(requestUrl) {
    var clientId = String(Math.random()).replace('.', '');
    var client = new Paho.MQTT.Client(requestUrl, clientId);
    var connectOptions = {
        onSuccess: function () {
            console.log('connected');

            // subscribe to the drawing
            client.subscribe("your/mqtt/topic");

            // publish a lifecycle event
            message = new Paho.MQTT.Message('{"id":"' + credentials.identityId + '"}');
            message.destinationName = 'your/mqtt/topic';
            console.log(message);
            client.send(message);
        },
        useSSL: true,
        timeout: 3,
        mqttVersion: 4,
        onFailure: function () {
            console.error('connect failed');
        }
    };
    client.connect(connectOptions);

    client.onMessageArrived = function (message) {

        try {
            console.log("msg arrived: " +  message.payloadString);
        } catch (e) {
            console.log("error! " + e);
        }

    };
}

Documentation for the credentials.get call, here

Remember to authorize your IAM role for subscribing / publishing as well. Here's a sample:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "iot:Connect"
            ],
            "Resource": "*"
        },
        {
            "Effect": "Allow",
            "Action": "iot:Receive",
            "Resource": "*"
        },
        {
            "Effect": "Allow",
            "Action": "iot:Subscribe",
            "Resource": [
                "arn:aws:iot:us-east-1::your/mqtt/topic"
            ]
        },
        {
            "Effect": "Allow",
            "Action": "iot:Publish",
            "Resource": [
                "arn:aws:iot:us-east-1::your/mqtt/topic"
            ]
        }
    ]
}

这篇关于如何使用AWS IoT向Web浏览器发送消息/从Web浏览器接收消息的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！