Add try-catch for channel closing in testing

README.md

@@ -203,8 +203,14 @@ export RABBIT_HOST=0.0.0.0
 export RABBIT_PORT=5672
 export RABBIT_USERNAME=root
 export RABBIT_PASSWORD=toor
+# these commands are for reconnecting test
+export START_RABBIT_COMMAND="docker start rabbitmq"
+export STOP_RABBIT_COMMAND="docker stop rabbitmq"
 ```
 
 and perform:
 
-`source ./test/test.env && npm test`
+```
+source ./test/test.env && npm test
+source ./test/test.env && node ./reconnect-example/rabbit-reconnect-test.js
+```

index.js

@@ -13,8 +13,6 @@ module.exports = function () {
             container.register("servicePubQueueRabbit", require("./lib/service_pub_queue_rabbit"));
             container.register("serviceSubQueueRabbit", require("./lib/service_sub_queue_rabbit"));
             container.alias("serviceSubQueue", "serviceSubQueueRabbit");
-
-            container.register("amqp", require("./lib/service_amqp"));
         },
         *onInit(container) {
             let service = yield container.resolve("service");
@@ -30,4 +28,4 @@ module.exports = function () {
             service.addModule("sub-queue-rabbit", serviceSubQueueRabbit);
         }
     };
-};
+};

lib/Rabbit.js

@@ -0,0 +1,287 @@
+const amqp = require("amqplib");
+
+/*
+ * This class support some action defined by configuration:
+ * - pubQueue --> publish to a queue
+ * - pub --> publish to exchange that will be fanned-out to multiple queue
+ * - subQueue --> subscribe to a queue
+ * - sub --> subscribe to exchange
+ */
+
+const defaultConfig = {
+    connection: {
+        host: "localhost",
+        port: "5627",
+        user: "guest",
+        password: "",
+        secure: false,
+        connectionString: "",
+    },
+    serviceName: "unnamed-service",
+    namespace: "default",
+    prefetch: 5,
+    reconnectDelay: 100,
+    /*
+     * pubQueuePayload?: {},            // Necessary for: pub + pubQueue
+     * pubQueue?: {                     // Necessary for: pubQueue
+     *    [serviceName]: string[],      // `eventName`
+     * },
+     * pubPayload?: {},                 // Necessary for: pub + pubQueue
+     * pub?: {                          // Necessary for: pub
+     *    [eventName]: string,          // `triggerName`
+     * },
+     * subQueue?: {                     // Necessary for: subQueue
+     *    [eventName]: (payload) => void,
+     * },
+     * publisher?: {                    // Necessary for: sub
+     *    [registryName: string {
+     *        [eventName]: string,
+     *    }
+     * },
+     * sub: {                           // Necessary for: sub
+     *    [registryName: string {
+     *        [eventName]: (payload) => void,
+     *    }
+     * },
+     * subNotification: {               // Necessary for: sub
+     *    [eventName]: (payload) => void,
+     * },
+     */
+};
+
+function getCompleteConfig(config) {
+    const completeConfig = Object.assign({}, defaultConfig, config);
+    return completeConfig;
+}
+
+function getConnectionString(config) {
+    const { secure, user, password, host, port, connectionString } = config.connection;
+    if (connectionString) {
+        return connectionString;
+    } else {
+        const protocol = (typeof secure === "boolean" && secure) ? "amqps" : "amqp";
+        const protocolBasedPort = protocol === "amqps" ? 5671 : 5672;
+        if (user && password) {
+            return `${protocol}://${user}:${password}@${host}:${port}`;
+        }
+        return `${protocol}://${host}:${port}`;
+    }
+}
+
+async function sleep(delay) {
+    return new Promise((resolve, reject) => {
+        setTimeout(resolve, delay);
+    });
+}
+
+class Rabbit {
+
+    constructor(config = {}, logger = console) {
+        this._connection = null;
+        this._config = getCompleteConfig(config);
+        this._logger = logger;
+        this._connectionString = getConnectionString(this._config);
+        this._run();
+    }
+
+    async publish(config) {
+        if (this._connection && !("pubPayload" in this._config)) {
+            if ("pub" in config) {
+                this._config.pub = config.pub;
+            }
+            if ("pubPayload" in config) {
+                this._config.pubPayload = config.pubPayload;
+            }
+            try {
+                await this._pub();
+            } catch (error) {
+                const { reconnectDelay } = this._config;
+                await sleep(reconnectDelay);
+                await this.publish(config);
+            }
+        } else {
+            const { reconnectDelay } = this._config;
+            await sleep(reconnectDelay);
+            await this.publish(config);
+        }
+    }
+
+    async publishQueue(config) {
+        if (this._connection && !("pubQueuePayload" in this._config)) {
+            if ("pubQueue" in config) {
+                this._config.pubQueue = config.pubQueue;
+            }
+            if ("pubQueuePayload" in config) {
+                this._config.pubQueuePayload = config.pubQueuePayload;
+            }
+            try {
+                await this._pubQueue();
+            } catch (error) {
+                const { reconnectDelay } = this._config;
+                await sleep(reconnectDelay);
+                await this.publishQueue(config);
+            }
+        } else {
+            const { reconnectDelay } = this._config;
+            await sleep(reconnectDelay);
+            await this.publishQueue(config);
+        }
+    }
+
+    async _run() {
+        const { reconnectDelay } = this._config;
+        try {
+            // create connection
+            this._connection = await amqp.connect(this._connectionString);
+            this._logger.info("Connected to rmq.");
+            this._connection.on("error", async (error) => {
+                this._connection = null;
+                this._logger.error("Connection error : ", error);
+                await sleep(reconnectDelay);
+                await this._run();
+            });
+            this._connection.on("close", async (error) => {
+                this._connection = null;
+                this._logger.error("Connection close : ", error);
+                await sleep(reconnectDelay);
+                await this._run();
+            });
+            // process pubSub handler
+            await this._subQueue();
+            await this._sub();
+            await this._pubQueue();
+            await this._pub();
+            // add to channels
+        } catch (error) {
+            this._connection = null;
+            this._logger.warn("Failed to connect to rmq.", error);
+            await sleep(reconnectDelay);
+            this._logger.info("Attempting to reconnect to rmq.");
+            await this._run();
+        }
+    }
+
+    async _pub() {
+        // "pubPayLoad" might contains "false" or "null"
+        if (!this._config.pub || !this._connection) {
+            return false;
+        }
+        // extract config
+        const { namespace, pub, pubPayload, serviceName } = this._config;
+        // create channel & publish payload
+        for (const eventName in pub) {
+            const triggerName = pub[eventName];
+            const exchangeName = `${namespace}.${serviceName}.${eventName}`;
+            const channel = await this._connection.createChannel();
+            await channel.assertExchange(exchangeName, "fanout", { durable: true });
+            // Only publish if payload exists
+            if ("pubPayload" in this._config) {
+                const content = JSON.stringify(pubPayload);
+                channel.publish(exchangeName, "", Buffer.from(content), { persistent: true });
+            }
+        }
+        delete this._config.pubPayload;
+        return true;
+    }
+
+    async _sub() {
+        if (!this._config.sub || !this._connection) {
+            return false;
+        }
+        // extract config
+        const { namespace, serviceName, sub, subNotification, publisher } = this._config;
+        // create channel & listen to event
+        for (const registryName in sub) {
+            for (const eventName in sub[registryName]) {
+                const publisherName = registryName in publisher && eventName in publisher[registryName] ? publisher[registryName][eventName] : "publisher";
+                const callback = sub[registryName][eventName];
+                const exchangeName = `${namespace}.${publisherName}.${eventName}`;
+                const queueName = `${namespace}.${publisherName}.${serviceName}.${eventName}`;
+                const channel = await this._connection.createChannel();
+                await channel.assertQueue(queueName, {durable: true});
+                await channel.assertExchange(exchangeName, "fanout", {durable: true});
+                await channel.bindQueue(queueName, exchangeName, "");
+                channel.consume(queueName, (message) => {
+                    try {
+                        const payload = JSON.parse(message.content.toString());
+                        callback(payload);
+                        channel.ack(message);
+                    } catch (error) {
+                        channel.nack(message);
+                    }
+                });
+            }
+        }
+        // create notification channel & listen to event
+        for (const eventName in subNotification) {
+            const callback = subNotification[eventName];
+            const queueName = `${namespace}.${serviceName}.${eventName}`;
+            const channel = await this._connection.createChannel();
+            channel.assertQueue(queueName, {durable: true});
+            channel.consume(queueName, (message) => {
+                try {
+                    const payload = JSON.parse(message.content.toString());
+                    callback(payload);
+                    channel.ack(message);
+                } catch (error) {
+                    channel.nack(message);
+                }
+            });
+        }
+        return true;
+    }
+
+    async _pubQueue() {
+        if (!this._config.pubQueue || !this._connection) {
+            return false;
+        }
+        // extract config
+        const { namespace, prefetch, pubQueue, pubQueuePayload } = this._config;
+        // create channel & publish payload
+        for (const serviceName in pubQueue) {
+            const eventList = pubQueue[serviceName];
+            for (const eventName of eventList) {
+                const queueName = `${namespace}.queue.${serviceName}.${eventName}`;
+                const channel = await this._connection.createChannel();
+                await channel.prefetch(prefetch);
+                channel.assertQueue(queueName, {durable: true});
+                // Only publish if payload exists
+                if ("pubQueuePayload" in this._config) {
+                    const content = JSON.stringify(pubQueuePayload);
+                    channel.sendToQueue(queueName, Buffer.from(content), { persistent: true });
+                }
+            }
+        }
+        delete this._config.pubQueuePayload;
+        return true;
+    }
+
+    async _subQueue() {
+        if (!this._config.subQueue || !this._connection) {
+            return false;
+        }
+        // extract config
+        const { namespace, prefetch, serviceName, subQueue } = this._config;
+        // create channel & listen to event
+        for (const eventName in subQueue) {
+            const callback = subQueue[eventName];
+            const queueName = `${namespace}.queue.${serviceName}.${eventName}`;
+            const channel = await this._connection.createChannel();
+            await channel.prefetch(prefetch);
+            channel.assertQueue(queueName, {durable: true});
+            channel.consume(queueName, (message) => {
+                try {
+                    const payload = JSON.parse(message.content.toString());
+                    // console.error("RECEIVE", payload);
+                    callback(payload);
+                    channel.ack(message);
+                } catch (error) {
+                    channel.nack(message);
+                }
+            });
+        }
+        return true;
+    }
+
+}
+module.exports = Rabbit;