Make paths and Aphlict instance names less ambiguous

Summary:
Fixes T10783 (what little of it remains). Ref T10697.

Aphlict currently uses request paths for two different things:

  - multi-tenant instancing in the Phacility cluster (each instance gets its own namespace within an Aphlict server);
  - some users configure nginx and apache to do proxying or SSL termination based on the path.

Currently, these can collide.

Put a "~" before the instance name to make it unambiguous. At some point we can possibly just use a GET parameter, but I think there was some reason I didn't do that originally and this sequence of changes is disruptive enough already.

Test Plan: Saw local Aphlict unambiguously recognize "local.phacility.com" as instance "local", with a "~"-style URI.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10697, T10783

Differential Revision: https://secure.phabricator.com/D15705

src/applications/notification/client/PhabricatorNotificationServerRef.php

@@ -162,7 +162,7 @@ final class PhabricatorNotificationServerRef
   public function getWebsocketURI($to_path = null) {
     $instance = PhabricatorEnv::getEnvConfig('cluster.instance');
     if (strlen($instance)) {
-      $to_path = $to_path.$instance.'/';
+      $to_path = $to_path.'~'.$instance.'/';
     }
 
     $uri = $this->getURI($to_path);

support/aphlict/server/lib/AphlictClientServer.js

@@ -52,18 +52,33 @@ JX.install('AphlictClientServer', {
       response.end('HTTP/501 Use Websockets\n');
     },
 
+    _parseInstanceFromPath: function(path) {
+      // If there's no "~" marker in the path, it's not an instance name.
+      // Users sometimes configure nginx or Apache to proxy based on the
+      // path.
+      if (path.indexOf('~') === -1) {
+        return 'default';
+      }
+
+      var instance = path.split('~')[1];
+
+      // Remove any "/" characters.
+      instance = instance.replace(/\//g, '');
+      if (!instance.length) {
+        return 'default';
+      }
+
+      return instance;
+    },
+
     listen: function() {
       var self = this;
       var server = this._server.listen.apply(this._server, arguments);
       var wss = new WebSocket.Server({server: server});
 
       wss.on('connection', function(ws) {
-        var instance = url.parse(ws.upgradeReq.url).pathname;
+        var path = url.parse(ws.upgradeReq.url).pathname;
-
+        var instance = self._parseInstanceFromPath(path);
-        instance = instance.replace(/\//g, '');
-        if (!instance.length) {
-          instance = 'default';
-        }
 
         var listener = self.getListenerList(instance).addListener(ws);