Remove deprecated drain event

README.md

@@ -158,17 +158,6 @@ So please attach the error listener to node_redis.
 
 `client` will emit `end` when an established Redis server connection has closed.
 
-### "drain" (deprecated)
-
-`client` will emit `drain` when the TCP connection to the Redis server has been buffering, but is now
-writable. This event can be used to stream commands in to Redis and adapt to backpressure.
-
-If the stream is buffering `client.should_buffer` is set to true. Otherwise the variable is always set to false.
-That way you can decide when to reduce your send rate and resume sending commands when you get `drain`.
-
-You can also check the return value of each command as it will also return the backpressure indicator (deprecated).
-If false is returned the stream had to buffer.
-
 ### "warning"
 
 `client` will emit `warning` when password was set but none is needed and if a deprecated option / function / similar is used.
@@ -260,13 +249,6 @@ NOTE: Your call to `client.auth()` should not be inside the ready handler. If
 you are doing this wrong, `client` will emit an error that looks
 something like this `Error: Ready check failed: ERR operation not permitted`.
 
-## backpressure
-
-### stream
-
-The client exposed the used [stream](https://nodejs.org/api/stream.html) in `client.stream` and if the stream or client had to [buffer](https://nodejs.org/api/stream.html#stream_writable_write_chunk_encoding_callback) the command in `client.should_buffer`.
-In combination this can be used to implement backpressure by checking the buffer state before sending a command and listening to the stream [drain](https://nodejs.org/api/stream.html#stream_event_drain) event.
-
 ## client.quit()
 
 This sends the quit command to the redis server and ends cleanly right after all running commands were properly handled.

examples/backpressure_drain.js

@@ -1,34 +0,0 @@
-'use strict';
-
-var redis = require('../index');
-var client = redis.createClient();
-var remaining_ops = 100000;
-var paused = false;
-
-function op () {
-    if (remaining_ops <= 0) {
-        console.error('Finished.');
-        process.exit(0);
-    }
-
-    remaining_ops--;
-    client.hset('test hash', 'val ' + remaining_ops, remaining_ops);
-    if (client.should_buffer === true) {
-        console.log('Pausing at ' + remaining_ops);
-        paused = true;
-    } else {
-        setTimeout(op, 1);
-    }
-}
-
-client.on('drain', function () {
-    if (paused) {
-        console.log('Resuming at ' + remaining_ops);
-        paused = false;
-        process.nextTick(op);
-    } else {
-        console.log('Got drain while not paused at ' + remaining_ops);
-    }
-});
-
-op();

index.js

@@ -115,19 +115,8 @@ function RedisClient (options, stream) {
     this.create_stream();
     // The listeners will not be attached right away, so let's print the deprecation message while the listener is attached
     this.on('newListener', function (event) {
-        if (event === 'drain') {
+        if ((event === 'message_buffer' || event === 'pmessage_buffer' || event === 'messageBuffer' || event === 'pmessageBuffer') && !this.buffers && !this.message_buffers) {
-            this.warn(
+            this.reply_parser.setReturnBuffers(true);
-                'The drain event listener is deprecated and will be removed in v.3.0.0.\n' +
-                'If you want to keep on listening to this event please listen to the stream drain event directly.'
-            );
-        } else if ((event === 'message_buffer' || event === 'pmessage_buffer' || event === 'messageBuffer' || event === 'pmessageBuffer') && !this.buffers && !this.message_buffers) {
-            if (this.reply_parser.name !== 'javascript') {
-                return this.warn(
-                    'You attached the "' + event + '" listener without the returnBuffers option set to true.\n' +
-                    'Please use the JavaScript parser or set the returnBuffers option to true to return buffers.'
-                );
-            }
-            this.reply_parser.optionReturnBuffers = true;
             this.message_buffers = true;
             this.handle_reply = handle_detect_buffers_reply;
         }
@@ -243,10 +232,6 @@ RedisClient.prototype.create_stream = function () {
         self.connection_gone('end');
     });
 
-    this.stream.on('drain', function () {
-        self.drain();
-    });
-
     // Fire the command before redis is connected to be sure it's the first fired command
     if (this.auth_pass !== undefined) {
         this.ready = true;
@@ -479,7 +464,6 @@ RedisClient.prototype.send_offline_queue = function () {
         debug('Sending offline command: ' + command_obj.command);
         this.internal_send_command(command_obj);
     }
-    this.drain();
 };
 
 var retry_connection = function (self, error) {
@@ -612,11 +596,6 @@ RedisClient.prototype.return_error = function (err) {
     utils.callback_or_emit(this, command_obj.callback, err);
 };
 
-RedisClient.prototype.drain = function () {
-    this.emit('drain');
-    this.should_buffer = false;
-};
-
 function normal_reply (self, reply) {
     var command_obj = self.command_queue.shift();
     if (typeof command_obj.callback === 'function') {

test/node_redis.spec.js

@@ -952,28 +952,6 @@ describe('The node_redis client', function () {
 
             describe('enable_offline_queue', function () {
                 describe('true', function () {
-                    it('should emit drain if offline queue is flushed and nothing to buffer', function (done) {
-                        client = redis.createClient({
-                            parser: parser,
-                            no_ready_check: true
-                        });
-                        var end = helper.callFuncAfter(done, 3);
-                        client.set('foo', 'bar');
-                        client.get('foo', end);
-                        client.on('warning', function (msg) {
-                            assert.strictEqual(
-                                msg,
-                                'The drain event listener is deprecated and will be removed in v.3.0.0.\n' +
-                                'If you want to keep on listening to this event please listen to the stream drain event directly.'
-                            );
-                            end();
-                        });
-                        client.on('drain', function () {
-                            assert(client.offline_queue.length === 0);
-                            end();
-                        });
-                    });
-
                     it('does not return an error and enqueues operation', function (done) {
                         client = redis.createClient(9999, null, {
                             parser: parser