From 834cbcf7a58c4b99ef9d521302e2b14605059c08 Mon Sep 17 00:00:00 2001
From: Guillermo Rauch <rauchg@gmail.com>
Date: Fri, 10 Aug 2012 10:39:00 -0700
Subject: [PATCH 1/4] README: added flush/drain docs

---
 README.md | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 173765d6..2a26970b 100644
--- a/README.md
+++ b/README.md
@@ -97,6 +97,18 @@ For more information on the client refer to the
 
 These are exposed by `require('engine.io')`:
 
+##### Events
+
+- `flush`
+    - Called when a socket buffer is being flushed.
+    - **Arguments**
+      - `Socket`: socket being flushed
+      - `Array`: write buffer
+- `drain`
+    - Called when a socket buffer is drained
+    - **Arguments**
+      - `Socket`: socket being flushed
+
 ##### Properties
 
 - `protocol` _(Number)_: protocol revision number
@@ -140,7 +152,7 @@ The main server/manager. _Inherits from EventEmitter_.
 ##### Events
 
 - `connection`
-    - Fired when a new connection is established. 
+    - Fired when a new connection is established.
     - **Arguments**
       - `Socket`: a Socket object
 
@@ -215,6 +227,12 @@ A representation of a client. _Inherits from EventEmitter_.
     - Fired when an error occurs.
     - **Arguments**
       - `Error`: error object
+- `flush`
+    - Called when the write buffer is being flushed.
+    - **Arguments**
+      - `Array`: write buffer
+- `drain`
+    - Called when the write buffer is drained
 
 ##### Properties
 

From 271585189f757ea9eb9344aa3af828cfc7735758 Mon Sep 17 00:00:00 2001
From: Guillermo Rauch <rauchg@gmail.com>
Date: Fri, 10 Aug 2012 10:39:09 -0700
Subject: [PATCH 2/4] socket: added flush/drain events (fixes #56)

---
 lib/socket.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/socket.js b/lib/socket.js
index 526c1fe4..2d1f0286 100644
--- a/lib/socket.js
+++ b/lib/socket.js
@@ -252,8 +252,12 @@ Socket.prototype.flush = function () {
   if ('closed' != this.readyState && this.transport.writable
     && this.writeBuffer.length) {
     debug('flushing buffer to transport');
+    this.emit('flush', this);
+    this.server.emit('flush', this, this.writeBuffer);
     this.transport.send(this.writeBuffer);
     this.writeBuffer = [];
+    this.emit('drain');
+    this.server.emit('drain', this);
   }
 };
 
@@ -273,7 +277,7 @@ Socket.prototype.getAvailableUpgrades = function () {
     }
   }
   return availableUpgrades;
-}
+};
 
 /**
  * Closes the socket and underlying transport.

From b948f858fbf9fedfd699de6ced1f59810d4cf8f2 Mon Sep 17 00:00:00 2001
From: Guillermo Rauch <rauchg@gmail.com>
Date: Fri, 10 Aug 2012 10:45:48 -0700
Subject: [PATCH 3/4] socket: fix `flush` event parameter

---
 lib/socket.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/socket.js b/lib/socket.js
index 2d1f0286..78db819e 100644
--- a/lib/socket.js
+++ b/lib/socket.js
@@ -252,7 +252,7 @@ Socket.prototype.flush = function () {
   if ('closed' != this.readyState && this.transport.writable
     && this.writeBuffer.length) {
     debug('flushing buffer to transport');
-    this.emit('flush', this);
+    this.emit('flush', this.writeBuffer);
     this.server.emit('flush', this, this.writeBuffer);
     this.transport.send(this.writeBuffer);
     this.writeBuffer = [];

From 81a6e76426f9bc2ad891a2c0956c98b6a0c2884b Mon Sep 17 00:00:00 2001
From: Guillermo Rauch <rauchg@gmail.com>
Date: Fri, 10 Aug 2012 10:46:00 -0700
Subject: [PATCH 4/4] test: added flush/drain events tests

---
 test/server.js | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/test/server.js b/test/server.js
index 5d75983f..743cc35a 100644
--- a/test/server.js
+++ b/test/server.js
@@ -558,6 +558,38 @@ describe('server', function () {
         });
       });
     });
+
+    it('should trigger a flush/drain event', function(done){
+      var engine = listen({ allowUpgrades: false }, function(port){
+        engine.on('connection', function(socket){
+          var totalEvents = 4;
+
+          engine.on('flush', function(sock, buf){
+            expect(sock).to.be(socket);
+            expect(buf).to.be.an('array');
+            --totalEvents || done();
+          });
+          socket.on('flush', function(buf){
+            expect(buf).to.be.an('array');
+            --totalEvents || done();
+          });
+
+          engine.on('drain', function(sock){
+            expect(sock).to.be(socket);
+            expect(socket.writeBuffer.length).to.be(0);
+            --totalEvents || done();
+          });
+          socket.on('drain', function(){
+            expect(socket.writeBuffer.length).to.be(0);
+            --totalEvents || done();
+          });
+
+          socket.send('aaaa');
+        });
+
+        new eioc.Socket('ws://localhost:%d'.s(port));
+      });
+    });
   });
 
   describe('upgrade', function () {