No dependency on Flash

If you know a little bit about HTML5 then you know that part of its motivation is to eliminate the need for proprietary plugins for rich media. So, instead of requiring a Flash plugin in your browser, Zeya server uses an audio embedding feature of the HTML5 standard, which allows you to embed a ogg file using the <audio> </audio> tag (Refer to http://www.w3schools.com/html5/tag_audio.asp). The Zeya server decodes music files in non-Ogg formats and encodes your music back as Ogg streams and serves it. (Hence the need for flac and mp3 decoders.)

Using zeya.py

As you might have already guessed, zeya.py is the starting point of the Zeya server. Currently, zeya.py takes the following options from the command line:

$ ./zeya.py --help
Usage: zeya.py [OPTIONS]

Options:
  -h, --help
      Display this help message.

  --backend=BACKEND
      Specify the backend to use. Acceptable values:
        dir:      (default) read a directory's contents recursively;
                  see --path
       rhythmbox: read from current user's Rhythmbox library

  --path=PATH
      Directory in which to look for music, under --backend=dir.
      (Default: ./)

  -b, --bitrate=N
      Specify the bitrate for output streams, in kbits/sec.
      (default: 64)

  -p, --port=PORT
      Listen for requests on the specified port. (default: 8080)

  --basic_auth_file=FILENAME
      Require basic HTTP authentication and only allow users named in
      the specified file. The file should be in 'htpasswd' format.

The option values are:

• backend: Zeya supports two backends for serving music. You can ask Zeya to

  serve music from a directory on your filesystem which contains the music files. By default, Zeya assumes this as the backend and looks for music files in the location from which Zeya server is started. The other option is to tell Zeya to read the music to serve from the current user's Rhythmbox library (in which case you must have a Rhythmbox library).

• path: The 'path' option is used to specify the location for the music files in

  case you are using the directory backend.

• port: As you saw above, Zeya binds to port 8080 by default. You may change

  that using the option '--port'

• bitrate: The bitrate at which audio is streamed to the clients

• basic_auth_file: You can make use of basic HTTP authentication by specifying a

  user/password file in 'htpasswd' file format. Enabling this option, you can control who is able to acess the services of Zeya. Once you enable this option, an authentication dialog pops up in the browser and only if the authentication is successful, will Zeya start streaming music.

Zeya's music database

If you are using the directory backend to serve your music, you will notice the file 'zeya.db' in your music directory. This is Zeya's music database. It contains a three tuple (Artist, album, title) for each music file in the directory. It uses this information to load the music library in the client. Zeya uses the TagPy library for obtaining this information from the music files.

Source tour of Zeya

Now that we've looked at Zeya from a user's perspective, I would like to take you on a tour of the source code of Zeya. An intermediate knowledge of Python, basic JavaScript and HTML, simple client-server computing concepts and you are good to go. Needless to say, you will derive the maximum benefit from this section if you browse through the source code along with this article. Let's get started.

Alphabetically, these are the Python source files and what they do:

• backends.py: The code in this file acts as interface with the supported backends.

  All backends should implement the Python interface 'LibraryBackend' defined in this file.

• common.py: A small file containing some utility functions

• decoders.py: The code in this file interfaces with the system's decoders

  for mp3 and flac files.

• directory.py: This implements the directory backend of Zeya.

• options.py: This handles the command line option parsing, error

  handling and sets default values for options.

• rhythmbox.py: This file implements the Rhythmbox backend

• zeyaclient.py: This is a sample implementation of a non-web, rudimentary

  command line client for Zeya.

• zeya.py: This is the main code for Zeya which takes care of

  serving music to clients by calling upon various functions from the previous files.

• zeyatest.py: This is the Zeya test suite.

• resources/library.html: This is the HTML page for the web based client that you

  see when you open the URL to Zeya in your browser.

• resources/zeya.js: This is a JavaScript file which implements the web based

  client functionality for communicating with the Zeya server.

• testdata/: This sub-directory contains some test data for the test suite.

• doc/: This sub-directory contains the Docbook sources for the Zeya manual pages.

Music Player Daemon

Music Playing Daemon (mpd) is a daemon that servers music to connected clients. Compared to Zeya, 'mpd' is a more feature rich. mpd is known to run on all the major Linux distributions and other Unix systems such as OpenSolaris, FreeBSD, NetBSD and MacOS X.

Clients for mpd exist as desktop clients, command line utilities and in the form of web applications. It's very popular in the community of music lovers and a number of hacks for doing cool stuff are documented at the project website. For further details on mpd, please see Resources.

GNUMP3D

GNUMP3D is a streaming server for MP3s, OGG vorbis files, movies and other media formats. It is no longer maintained as of a couple of years back, but the source code is still there to try out. It's completely written in Perl. It's very simple to setup and use, like Zeya.

Please look up the GNUMP3D homepage given in the Resources.

Ampache

Ampache is a PHP web application which can be setup to serve music over HTTP. It needs an Apache Web server and MySQL database. It can also be setup to act as a client for the Music Playing Daemon (mpd).

Installation and configuration is modereately complex and detailed guidelines can be found at the project website given in the Resources.

Note that each of the above three projects require a Flash browser plugin to be installed at the client side.