feature(sockets): Add the option to use unix sockets instead of a hostname / port combination

README.md

@@ -37,6 +37,20 @@ bot.on('message', function(event) {
 bot.matchMessage(/^hi/, function(event) {
 	event.reply('hello there!');
 });
+
+// Connect via Unix socket
+var bot = new IRC.Client();
+bot.connect({
+	path: '/tmp/irc.sock',
+	nick: 'prawnsbot'
+});
+
+// ... optionally with TLS
+bot.connect({
+	path: '/tmp/irc.sock',
+	tls: true,
+	nick: 'prawnsbot'
+});
 ~~~
 
 #### Channel/buffer objects. Great for building clients

docs/clientapi.md

@@ -74,7 +74,9 @@ Add middleware to handle the events for the client instance
 
 ##### `.connect([connect_options])`
 Start connecting to the IRC network. If `connect_options` is provided it will
-override any options given to the constructor.
+override any options given to the constructor. Accepts a `path` option to connect
+via a Unix domain socket instead of `host`/`port`. Can be combined with `tls`/`ssl`
+for TLS over Unix socket.
 
 ##### `.raw(raw_data_line)`
 Send a raw line to the IRC server

src/transports/net.js

@@ -126,7 +126,15 @@ module.exports = class Connection extends EventEmitter {
             }).catch(this.onSocketError.bind(this));
         } else {
             let socket = null;
-            if (options.tls || options.ssl) {
+            if ((options.tls || options.ssl) && options.path) {
+                this.debugOut('Using TLS over Unix socket');
+                socket = this.socket = tls.connect({
+                    path: options.path,
+                    rejectUnauthorized: options.rejectUnauthorized,
+                    key: options.client_certificate && options.client_certificate.private_key,
+                    cert: options.client_certificate && options.client_certificate.certificate,
+                });
+            } else if (options.tls || options.ssl) {
                 socket = this.socket = tls.connect({
                     servername: sni,
                     host: ircd_host,
@@ -137,6 +145,12 @@ module.exports = class Connection extends EventEmitter {
                     localAddress: options.outgoing_addr,
                     family: this.getAddressFamily(options.outgoing_addr)
                 });
+            } else if (options.path) {
+                this.debugOut('Using path for socket');
+
+                socket = this.socket = net.connect({
+                    path: options.path
+                });
             } else {
                 socket = this.socket = net.connect({
                     host: ircd_host,