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Notifications User Guide: Setup and Configuration
Phorge Administrator and User Documentation (Configuration)

Guide to setting up notifications.

Overview

By default, Phorge delivers information about events (like users creating tasks or commenting on code reviews) through email and in-application notifications.

Phorge can also be configured to deliver notifications in real time, by popping up a message in any open browser windows if something has happened or an object has been updated.

To enable real-time notifications:

  • Configure and start the notification server, as described below.
  • Adjust notification.servers to point at it.

This document describes the process in detail.

Supported Browsers

Notifications are supported for browsers which support WebSockets. This covers most modern browsers (like Chrome, Firefox, Safari, and recent versions of Internet Explorer) and many mobile browsers.

IE8 and IE9 do not support WebSockets, so real-time notifications won't work in those browsers.

Installing Node and Modules

The notification server uses Node.js, so you'll need to install it first.

To install Node.js, follow the instructions on nodejs.org.

You will also need to install the dependencies for Node. This needs to be installed into the notification server directory:

phorge/ $ cd support/aphlict/server/
phorge/support/aphlict/server/ $ npm install

Once Node.js and its dependencies are installed, you're ready to start the server.

Running the Aphlict Server

After installing Node.js, you can control the notification server with the bin/aphlict command. To start the server:

phorge/ $ bin/aphlict start

By default, the server must be able to listen on port 22280. If you're using a host firewall (like a security group in EC2), make sure traffic can reach the server.

The server configuration is controlled by a configuration file, which is separate from Phorge's configuration settings. The default file can be found at phorge/conf/aphlict/aphlict.default.json.

To make adjustments to the default configuration, either copy this file to create aphlict.custom.json in the same directory (this file will be used if it exists) or specify a configuration file explicitly with the --config flag:

phorge/ $ bin/aphlict start --config path/to/config.json

The configuration file has these settings:

  • servers: Required list. A list of servers to start.
  • logs: Optional list. A list of logs to write to.
  • cluster: Optional list. A list of cluster peers. This is an advanced feature.
  • pidfile: Required string. Path to a PID file.
  • memory.hint: Optional int. Suggestion to node about how much memory to use, via --max-old-stack-size. In most cases, this can be left unspecified.

Each server in the servers list should be an object with these keys:

  • type: Required string. The type of server to start. Options are admin or client. Normally, you should run one of each.
  • port: Required int. The port this server should listen on.
  • listen: Optional string. Which interface to bind to. By default, the admin server is bound to 127.0.0.1 (so only other services on the local machine can connect to it), while the client server is bound to 0.0.0.0 (so any client can connect).
  • ssl.key: Optional string. If you want to use SSL on this port, the path to an SSL key.
  • ssl.cert: Optional string. If you want to use SSL on this port, the path to an SSL certificate.
  • ssl.chain: Optional string. If you have configured SSL on this port, an optional path to a certificate chain file.

Each log in the logs list should be an object with these keys:

  • path: Required string. Path to the log file.

Each peer in the cluster list should be an object with these keys:

  • host: Required string. The peer host address.
  • port: Required int. The peer port.
  • protocol: Required string. The protocol to connect with, one of "http" or "https".

Cluster configuration is an advanced topic and can be omitted for most installs. For more information on how to configure a cluster, see Clustering Introduction and Cluster: Notifications.

The defaults are appropriate for simple cases, but you may need to adjust them if you are running a more complex configuration.

Configuring Phorge

After starting the server, configure Phorge to connect to it by adjusting notification.servers. This configuration option should have a list of servers that Phorge should interact with.

Normally, you'll list one client server and one admin server, like this:

[
  {
    "type": "client",
    "host": "phorge.mycompany.com",
    "port": 22280,
    "protocol": "https"
  },
  {
    "type": "admin",
    "host": "127.0.0.1",
    "port": 22281,
    "protocol": "http"
  }
]

This definition defines which services the user's browser will attempt to connect to. Most of the time, it will be very similar to the services defined in the Aphlict configuration. However, if you are sending traffic through a load balancer or terminating SSL somewhere before traffic reaches Aphlict, the services the browser connects to may need to have different hosts, ports or protocols than the underlying server listens on.

Verifying Server Status

After configuring notification.servers, navigate to ConfigServicesNotification Servers to verify that things are operational.

Troubleshooting

You can run aphlict in the foreground to get output to your console:

phorge/ $ ./bin/aphlict debug

Because the notification server uses WebSockets, your browser error console may also have information that is useful in figuring out what's wrong.

The server also generates a log, by default in /var/log/aphlict.log. You can change this location by adjusting configuration. The log may contain information that is useful in resolving issues.

SSL and HTTPS

If you serve Phorge over HTTPS, you must also serve websockets over HTTPS. Browsers will refuse to connect to ws:// websockets from HTTPS pages.

If a client connects to Phorge over HTTPS, Phorge will automatically select an appropriate HTTPS service from notification.servers and instruct the browser to open a websocket connection with wss://.

The simplest way to do this is configure Aphlict with an SSL key and certificate and let it terminate SSL directly.

If you prefer not to do this, two other options are:

  • run the websocket through a websocket-capable loadbalancer and terminate SSL there; or
  • run the websocket through nginx over the same socket as the rest of your web traffic.

See the next sections for more detail.

Terminating SSL with a Load Balancer

If you want to terminate SSL in front of the notification server with a traditional load balancer or a similar device, do this:

  • Point notification.servers at your load balancer or reverse proxy, specifying that the protocol is https.
  • On the load balancer or proxy, terminate SSL and forward traffic to the Aphlict server.
  • In the Aphlict configuration, listen on the target port with http.

Terminating SSL with Nginx

If you use nginx, you can send websocket traffic to the same port as normal HTTP traffic and have nginx proxy it selectively based on the request path.

This requires nginx 1.3 or greater. See the nginx documentation for details:

http://nginx.com/blog/websocket-nginx/

This is very complex, but allows you to support notifications without opening additional ports.

An example nginx configuration might look something like this:

/etc/nginx/conf.d/connection_upgrade.conf
map $http_upgrade $connection_upgrade {
    default upgrade;
    '' close;
}
/etc/nginx/conf.d/websocket_pool.conf
upstream websocket_pool {
    ip_hash;
    server 127.0.0.1:22280;
}
/etc/nginx/sites-enabled/phorge.example.com.conf
server {
  server_name phorge.example.com;
  root        /path/to/phorge/webroot;

  // ...

  location = /ws/ {
    proxy_pass http://websocket_pool;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
    proxy_read_timeout 999999999;
  }
}

With this approach, you should make these additional adjustments:

Phorge Configuration: The entry in notification.servers with type "client" should have these adjustments made:

  • Set host to the Phorge host.
  • Set port to the standard HTTPS port (usually 443).
  • Set protocol to "https".
  • Set path to /ws/, so it matches the special location in your nginx config.

You do not need to adjust the "admin" server.

Aphlict: Your Aphlict configuration should make these adjustments to the "client" server:

  • Do not specify any ssl.* options: nginx will send plain HTTP traffic to Aphlict.
  • Optionally, you can listen on 127.0.0.1 instead of 0.0.0.0, because the server will no longer receive external traffic.