primer cambio

node_modules/amqplib/lib/channel_model.js

@@ -0,0 +1,308 @@
+//
+//
+//
+
+'use strict';
+
+const EventEmitter = require('events');
+const promisify = require('util').promisify;
+const defs = require('./defs');
+const {BaseChannel} = require('./channel');
+const {acceptMessage} = require('./channel');
+const Args = require('./api_args');
+const {inspect} = require('./format');
+
+class ChannelModel extends EventEmitter {
+  constructor(connection) {
+    super();
+    this.connection = connection;
+
+    ['error', 'close', 'blocked', 'unblocked'].forEach(ev => {
+      connection.on(ev, this.emit.bind(this, ev));
+    });
+  }
+
+  close() {
+    return promisify(this.connection.close.bind(this.connection))();
+  }
+
+  updateSecret(newSecret, reason) {
+    return promisify(this.connection._updateSecret.bind(this.connection))(newSecret, reason);
+  }
+
+  async createChannel(options) {
+    const channel = new Channel(this.connection);
+    channel.setOptions(options);
+    await channel.open();
+    return channel;
+  }
+
+  async createConfirmChannel(options) {
+    const channel = new ConfirmChannel(this.connection);
+    channel.setOptions(options);
+    await channel.open();
+    await channel.rpc(defs.ConfirmSelect, {nowait: false}, defs.ConfirmSelectOk);
+    return channel;
+  }
+}
+
+// Channels
+
+class Channel extends BaseChannel {
+  constructor(connection) {
+    super(connection);
+    this.on('delivery', this.handleDelivery.bind(this));
+    this.on('cancel', this.handleCancel.bind(this));
+  }
+
+  // An RPC that returns a 'proper' promise, which resolves to just the
+  // response's fields; this is intended to be suitable for implementing
+  // API procedures.
+  async rpc(method, fields, expect) {
+    const f = await promisify(cb => {
+      return this._rpc(method, fields, expect, cb);
+    })();
+
+    return f.fields;
+  }
+
+  // Do the remarkably simple channel open handshake
+  async open() {
+    const ch = await this.allocate.bind(this)();
+    return ch.rpc(defs.ChannelOpen, {outOfBand: ""},
+                  defs.ChannelOpenOk);
+  }
+
+  close() {
+    return promisify(cb => {
+      return this.closeBecause("Goodbye", defs.constants.REPLY_SUCCESS,
+                      cb);
+    })();
+  }
+
+  // === Public API, declaring queues and stuff ===
+
+  assertQueue(queue, options) {
+    return this.rpc(defs.QueueDeclare,
+                    Args.assertQueue(queue, options),
+                    defs.QueueDeclareOk);
+  }
+
+  checkQueue(queue) {
+    return this.rpc(defs.QueueDeclare,
+                    Args.checkQueue(queue),
+                    defs.QueueDeclareOk);
+  }
+
+  deleteQueue(queue, options) {
+    return this.rpc(defs.QueueDelete,
+                    Args.deleteQueue(queue, options),
+                    defs.QueueDeleteOk);
+  }
+
+  purgeQueue(queue) {
+    return this.rpc(defs.QueuePurge,
+                    Args.purgeQueue(queue),
+                    defs.QueuePurgeOk);
+  }
+
+  bindQueue(queue, source, pattern, argt) {
+    return this.rpc(defs.QueueBind,
+                    Args.bindQueue(queue, source, pattern, argt),
+                    defs.QueueBindOk);
+  }
+
+  unbindQueue(queue, source, pattern, argt) {
+    return this.rpc(defs.QueueUnbind,
+                    Args.unbindQueue(queue, source, pattern, argt),
+                    defs.QueueUnbindOk);
+  }
+
+  assertExchange(exchange, type, options) {
+    // The server reply is an empty set of fields, but it's convenient
+    // to have the exchange name handed to the continuation.
+    return this.rpc(defs.ExchangeDeclare,
+                    Args.assertExchange(exchange, type, options),
+                    defs.ExchangeDeclareOk)
+      .then(_ok => { return { exchange }; });
+  }
+
+  checkExchange(exchange) {
+    return this.rpc(defs.ExchangeDeclare,
+                    Args.checkExchange(exchange),
+                    defs.ExchangeDeclareOk);
+  }
+
+  deleteExchange(name, options) {
+    return this.rpc(defs.ExchangeDelete,
+                    Args.deleteExchange(name, options),
+                    defs.ExchangeDeleteOk);
+  }
+
+  bindExchange(dest, source, pattern, argt) {
+    return this.rpc(defs.ExchangeBind,
+                    Args.bindExchange(dest, source, pattern, argt),
+                    defs.ExchangeBindOk);
+  }
+
+  unbindExchange(dest, source, pattern, argt) {
+    return this.rpc(defs.ExchangeUnbind,
+                    Args.unbindExchange(dest, source, pattern, argt),
+                    defs.ExchangeUnbindOk);
+  }
+
+  // Working with messages
+
+  publish(exchange, routingKey, content, options) {
+    const fieldsAndProps = Args.publish(exchange, routingKey, options);
+    return this.sendMessage(fieldsAndProps, fieldsAndProps, content);
+  }
+
+  sendToQueue(queue, content, options) {
+    return this.publish('', queue, content, options);
+  }
+
+  consume(queue, callback, options) {
+    // NB we want the callback to be run synchronously, so that we've
+    // registered the consumerTag before any messages can arrive.
+    const fields = Args.consume(queue, options);
+    return new Promise((resolve, reject) => {
+      this._rpc(defs.BasicConsume, fields, defs.BasicConsumeOk, (err, ok) => {
+        if (err) return reject(err);
+        this.registerConsumer(ok.fields.consumerTag, callback);
+        resolve(ok.fields);
+      });
+    });
+  }
+
+  async cancel(consumerTag) {
+    const ok = await promisify(cb => {
+      this._rpc(defs.BasicCancel, Args.cancel(consumerTag),
+            defs.BasicCancelOk,
+            cb);
+    })()
+    .then(ok => {
+      this.unregisterConsumer(consumerTag);
+      return ok.fields;
+    });
+  }
+
+  get(queue, options) {
+    const fields = Args.get(queue, options);
+    return new Promise((resolve, reject) => {
+      this.sendOrEnqueue(defs.BasicGet, fields, (err, f) => {
+        if (err) return reject(err);
+        if (f.id === defs.BasicGetEmpty) {
+          return resolve(false);
+        }
+        else if (f.id === defs.BasicGetOk) {
+          const fields = f.fields;
+          this.handleMessage = acceptMessage(m => {
+            m.fields = fields;
+            resolve(m);
+          });
+        }
+        else {
+          reject(new Error(`Unexpected response to BasicGet: ${inspect(f)}`));
+        }
+      });
+    });
+  }
+
+  ack(message, allUpTo) {
+    this.sendImmediately(
+      defs.BasicAck,
+      Args.ack(message.fields.deliveryTag, allUpTo));
+  }
+
+  ackAll() {
+    this.sendImmediately(defs.BasicAck, Args.ack(0, true));
+  }
+
+  nack(message, allUpTo, requeue) {
+    this.sendImmediately(
+      defs.BasicNack,
+      Args.nack(message.fields.deliveryTag, allUpTo, requeue));
+  }
+
+  nackAll(requeue) {
+    this.sendImmediately(defs.BasicNack,
+                         Args.nack(0, true, requeue));
+  }
+
+  // `Basic.Nack` is not available in older RabbitMQ versions (or in the
+  // AMQP specification), so you have to use the one-at-a-time
+  // `Basic.Reject`. This is otherwise synonymous with
+  // `#nack(message, false, requeue)`.
+  reject(message, requeue) {
+    this.sendImmediately(
+      defs.BasicReject,
+      Args.reject(message.fields.deliveryTag, requeue));
+  }
+
+  recover() {
+    return this.rpc(defs.BasicRecover,
+                    Args.recover(),
+                    defs.BasicRecoverOk);
+  }
+
+  qos(count, global) {
+    return this.rpc(defs.BasicQos,
+                    Args.prefetch(count, global),
+                    defs.BasicQosOk);
+  }
+}
+
+// There are more options in AMQP than exposed here; RabbitMQ only
+// implements prefetch based on message count, and only for individual
+// channels or consumers. RabbitMQ v3.3.0 and after treat prefetch
+// (without `global` set) as per-consumer (for consumers following),
+// and prefetch with `global` set as per-channel.
+Channel.prototype.prefetch = Channel.prototype.qos
+
+// Confirm channel. This is a channel with confirms 'switched on',
+// meaning sent messages will provoke a responding 'ack' or 'nack'
+// from the server. The upshot of this is that `publish` and
+// `sendToQueue` both take a callback, which will be called either
+// with `null` as its argument to signify 'ack', or an exception as
+// its argument to signify 'nack'.
+
+class ConfirmChannel extends Channel {
+  publish(exchange, routingKey, content, options, cb) {
+    this.pushConfirmCallback(cb);
+    return super.publish(exchange, routingKey, content, options);
+  }
+
+  sendToQueue(queue, content, options, cb) {
+    return this.publish('', queue, content, options, cb);
+  }
+
+  waitForConfirms() {
+    const awaiting = [];
+    const unconfirmed = this.unconfirmed;
+    unconfirmed.forEach((val, index) => {
+      if (val !== null) {
+        const confirmed = new Promise((resolve, reject) => {
+          unconfirmed[index] = err => {
+            if (val) val(err);
+            if (err === null) resolve();
+            else reject(err);
+          };
+        });
+        awaiting.push(confirmed);
+      }
+    });
+    // Channel closed
+    if (!this.pending) {
+      var cb;
+      while (cb = this.unconfirmed.shift()) {
+        if (cb) cb(new Error('channel closed'));
+      }
+    }
+    return Promise.all(awaiting);
+  }
+}
+
+module.exports.ConfirmChannel = ConfirmChannel;
+module.exports.Channel = Channel;
+module.exports.ChannelModel = ChannelModel;