Bind underlying socket to same domain as connection

fixes mysqljs#1243

Author: dougwilson

Changes.md

@@ -8,6 +8,7 @@ you spot any mistakes.
 
 * Add `POOL_CLOSED` code to "Pool is closed." error
 * Add `POOL_CONNLIMIT` code to "No connections available." error #1332
+* Bind underlying socket to same domain as connection #1243
 * Fix edge cases constructing long stack traces #1387
 * Fix Query stream to emit close after ending #1349 #1350
 * Fix type cast for BIGINT columns when number is negative #1376

lib/Connection.js

@@ -1,17 +1,17 @@
 var Crypto           = require('crypto');
+var Events           = require('events');
 var Net              = require('net');
 var tls              = require('tls');
 var ConnectionConfig = require('./ConnectionConfig');
 var Protocol         = require('./protocol/Protocol');
 var SqlString        = require('./protocol/SqlString');
 var Query            = require('./protocol/sequences/Query');
-var EventEmitter     = require('events').EventEmitter;
 var Util             = require('util');
 
 module.exports = Connection;
-Util.inherits(Connection, EventEmitter);
+Util.inherits(Connection, Events.EventEmitter);
 function Connection(options) {
-  EventEmitter.call(this);
+  Events.EventEmitter.call(this);
 
   this.config = options.config;
 
@@ -90,6 +90,17 @@ Connection.prototype.connect = function connect(options, callback) {
       ? Net.createConnection(this.config.socketPath)
       : Net.createConnection(this.config.port, this.config.host);
 
+    // Connect socket to connection domain
+    if (Events.usingDomains) {
+      if (this._socket.domain) {
+        this._socket.domain.remove(this._socket);
+      }
+
+      if (this.domain) {
+        this.domain.add(this._socket);
+      }
+    }
+
     var connection = this;
     this._protocol.on('data', function(data) {
        connection._socket.write(data);

test/unit/connection/test-connect-domain.js

@@ -0,0 +1,45 @@
+var assert = require('assert');
+var common = require('../../common');
+var domain = null;
+
+try {
+  domain = require('domain');
+} catch (e) {
+  common.skipTest('node ' + process.version + ' does not support domains');
+}
+
+var d0 = domain.create();
+var d1 = domain.create();
+
+var server = common.createFakeServer();
+
+server.listen(common.fakeServerPort, function (err) {
+  assert.ifError(err);
+
+  var connection = null;
+  var timer      = setInterval(function () {
+    if (connection.state !== 'authenticated') return;
+    clearInterval(timer);
+
+    assert.ok(!domain.active, 'no current domain');
+    connection.query('SELECT 1', function (err) {
+      assert.ifError(err);
+      assert.equal(domain.active, d0, 'current domain is d0');
+
+      connection.destroy();
+      server.destroy();
+    });
+  }, 200);
+
+  d0.run(function () {
+    connection = common.createConnection({port: common.fakeServerPort});
+    assert.equal(connection.domain, d0, 'connection belongs to d0');
+
+    d1.run(function () {
+      connection.connect(function (err) {
+        assert.ifError(err);
+        assert.equal(domain.active, d1, 'current domain is d1');
+      });
+    });
+  });
+});

test/unit/connection/test-connect-no-domain.js

@@ -0,0 +1,41 @@
+var assert = require('assert');
+var common = require('../../common');
+var domain = null;
+
+try {
+  domain = require('domain');
+} catch (e) {
+  common.skipTest('node ' + process.version + ' does not support domains');
+}
+
+var d0 = domain.create();
+
+var server = common.createFakeServer();
+
+server.listen(common.fakeServerPort, function (err) {
+  assert.ifError(err);
+
+  var connection = common.createConnection({port: common.fakeServerPort});
+  var timer      = setInterval(function () {
+    if (connection.state !== 'authenticated') return;
+    clearInterval(timer);
+
+    assert.ok(!domain.active, 'no current domain');
+    connection.query('SELECT 1', function (err) {
+      assert.ifError(err);
+      assert.equal(domain.active, null, 'query is not bound to domain');
+
+      connection.destroy();
+      server.destroy();
+    });
+  }, 200);
+
+  assert.equal(connection.domain, null, 'connection is not bound to domain');
+
+  d0.run(function () {
+    connection.connect(function (err) {
+      assert.ifError(err);
+      assert.equal(domain.active, d0, 'current domain is d0');
+    });
+  });
+});