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static/pages/Build-your-open-source-multi-room-and-multi-provider-sound-server-with-Platypush-Mopidy-and-Snapcast.md

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+[//]: # (title: Build your multi-room and multi-provider sound server with Platypush, Mopidy and Snapcast)
+[//]: # (description: How to leverage Platypush and other open-source projects to build an extensible and versatile music server.)
+[//]: # (image: /img/mpd-1.png)
+[//]: # (published: 2019-10-22)
+
+Today’s abundance of music streaming services has created lots of opportunities to listen to whichever music you like
+wherever you like, but there’s a huge fragmentation problem that hasn’t been tackled seriously by the music tech
+industry yet.
+
+Spotify allows you to find and discover a lot of tunes, but not all the music is there.
+
+You may want to integrate your collection of mp3s into your Spotify collection, but that is simply not an option.
+
+You may have favourite tracks that are only available on SoundCloud or albums that aren’t available on Spotify, but
+you’ve purchased in the past on Google Music or iTunes, but there’s no way to have them all in one place: each of these
+solution comes with its separate app.
+
+You may want to integrate your favourite online radios or podcasts into your music app, but that’s, again, not an option
+— TuneIn, Podcast Addict or Google Podcasts are distinct apps.
+
+You may want to easily stream your playlists to any speaker or pair of headphones you own, but that’s not as easy as it
+sounds. You may have to replace your existing speakers with expensive solutions (like Sonos or Bose) to enjoy a proper
+multi-room setup. Apps like Spotify come with their solutions (e.g. Spotify Connect), but only a limited number of
+devices is supported and, again, it works as a solution only as long as you stream Spotify content from the Spotify app.
+
+There have been commercial solutions that have tried to tackle this fragmentation problem and provide you with the
+possibility to stream music from any app to any speaker without having to replace your audio system, but the situation
+isn’t that bright after Google
+has [discontinued its Chromecast Audio support](https://www.theverge.com/2019/1/11/18178751/google-chromecast-audio-discontinued-sale),
+and AirPlay works relatively well only as long as you’re in an Apple ecosystem.
+
+As of today the problem “how do I play whichever piece of music I like, from whichever service I like, on whichever
+device I like, all in one interface, without having to install 10 different apps” is still largely unsolved if you rely
+on commercial solutions.
+
+Luckily, we’ve got plenty of open source software around that comes to rescue. It requires a bit more work than just
+downloading an app and logging in, but the rewards are priceless.
+
+## One music server to rule them all
+
+[Mopidy](https://mopidy.com/) is one of the best open source solutions around when it comes to integrating multiple
+music services under one single interface. It’s entirely written in Python, it’s (almost) 100% compatible
+with [MPD](https://www.musicpd.org/doc/html/protocol.html), a music protocol that has been around since 2003 and comes
+with lots of compatible clients (command-line, web-based, mobile apps etc.), and there are countless plugins that let
+Mopidy integrate with any kind of music service around.
+
+It’s relatively easy to install mopidy on a RaspberryPi and turn it into a powerful music centre.
+
+- Add the mopidy repository to your apt lists and install the base package:
+
+```shell
+wget -q -O - https://apt.mopidy.com/mopidy.gpg | sudo apt-key add -
+
+# Run the following if you're running Raspbian/Debian Buster
+sudo wget -q -O /etc/apt/sources.list.d/mopidy.list https://apt.mopidy.com/buster.list
+
+# Run the following command if you're running Raspbian/Debian Stretch
+sudo wget -q -O /etc/apt/sources.list.d/mopidy.list https://apt.mopidy.com/stretch.list
+
+# Update the repositories and install mopidy
+sudo apt-get update
+sudo apt-get install mopidy mopidy-mpd
+```
+
+- Install any additional extension for the music services you like:
+
+```shell
+# Spotify support
+sudo apt-get install mopidy-spotify
+
+# Local files support
+sudo apt-get install mopidy-local
+
+# Dirble support
+sudo apt-get install mopidy-dirble
+
+# Podcast support
+sudo apt-get install mopidy-podcast mopidy-podcast-gpodder mopidy-podcast-itunes
+
+# Last.FM scrobbling support
+sudo apt-get install mopidy-scrobbler
+
+# Soma.FM support
+sudo apt-get install mopidy-somafm
+
+# Soundcloud support
+sudo apt-get install mopidy-soundcloud
+
+# TuneIn support
+sudo apt-get install mopidy-tunein
+
+# YouTube support
+sudo apt-get install mopidy-youtube
+```
+
+And there are even more extensions available for Mopidy - you may want to take a look on
+[their website](https://mopidy.com/ext/) to get an overview of the compatible services.
+
+Head to the pages of those extensions to find out whether they need some extra dependencies or extra configuration to be
+added to your `~/.config/mopidy/mopidy.conf` file.
+
+You may also want to make sure that the HTTP module is enabled in your mopidy configuration, since most of the web
+frontends (including Platypush) rely on it to interact with mopidy over websockets:
+
+```yaml
+[http]
+enabled = true
+hostname = 0.0.0.0
+port = 6680
+```
+
+There is also a wide range of frontend clients available for Mopidy, from command-line MPD clients to full-blown web
+clients that do a very good job replicating the UI of some of the most popular music apps around. Let's have a quick
+overview of my favourite solutions to interact with Mopidy:
+
+- `netcat`/`telnet`. Mopidy is compatible with the MPD protocol, and once started it will listen by default on port 6600
+  for MPD commands. It’s relatively straightforward to explore your library or control the playback even without
+  installing another client (although it’s probably not the most user-friendly way, but very good if you want to make
+  some scripts):
+  
+```shell
+$ echo status | nc localhost 6600
+OK MPD 0.19.0
+volume: 100
+repeat: 0
+random: 1
+single: 0
+consume: 0
+playlist: 3
+playlistlength: 1489
+xfade: 0
+state: stop
+song: 513
+songid: 560
+nextsong: 173
+nextsongid: 220
+OK
+
+$ echo currentsong | nc localhost 6600
+OK MPD 0.19.0
+file: spotify:track:218UgZapIcNRP9f38C5cMp
+Time: 365
+Artist: 3rd Force
+Album: Vital Force
+Title: Echoes Of A Dream
+Date: 1997
+Track: 6
+Pos: 513
+Id: 560
+AlbumArtist: 3rd Force
+X-AlbumUri: spotify:album:3mSCVZabNB0rUmpYgPkDuV
+OK
+
+$ echo play | nc localhost 6600
+OK MPD 0.19.0
+OK
+
+$ echo stop | nc localhost 6600
+OK MPD 0.19.0
+OK
+```
+
+- `mpc` is a tiny command-line utility that makes it a bit easier to interact with MPD/mopidy instances for scripting
+  purposes without handling low-level protocol messages:
+
+```shell
+sudo apt-get install mpc
+mpc help  # To see available commands
+mpc play  # Play the music
+```
+
+- `ncmpcpp` is a ncurses-based terminal client that I've been using for more than a decade, and it's probably one of
+  the lightest yet most versatile music clients I've seen around - and definitely my favourite:
+  
+```shell
+sudo apt-get install ncmpcpp
+```
+
+![ncmpcpp screenshot 1](../img/ncmpcpp-1.png)
+![ncmpcpp screenshot 2](../img/ncmpcpp-2.png)
+![ncmpcpp screenshot 3](../img/ncmpcpp-3.png)
+
+- `mopidy-iris` is probably one of the most user-friendly, well-maintained and feature-rich Mopidy clients around, and
+  it's compatible with desktop, tablet and mobile and it comes with a UI that successfully mimics that of many popular
+  music apps:
+
+```shell
+sudo apt-get install mopidy-iris
+```
+
+After installing it head to `http://your-raspberry:6680` and select Iris as the web interface.
+
+![iris interface](../img/mopidy-iris-1.jpeg)
+
+And you have many more compatible clients available (just check the list of extensions), from minimal, to feature-rich
+(such as MusicBox), to a specific client for party mode optimized for multiple users! And, being compatible with MPD,
+all the MPD clients out there should also work out of the box. And the list also includes a *Mopidy Mobile* app and
+several MPD apps for Android and iOS.
+
+## Hook Mopidy to Platypush
+
+You can connect Platypush to Mopidy. That provides you with one more UI for interacting with your instance (embedded in
+the Platypush web panel), and it opens a world of possibilities when it comes to automating music interactions.
+
+- Install Platypush with the HTTP and MPD dependencies:
+
+```shell
+[sudo] pip install 'platypush[http,mpd]'
+```
+
+- Enable the MPD/mopidy plugin and backend in your platypush configuration file:
+
+```yaml
+music.mpd:
+    host: localhost
+    port: 6600
+    
+backend.music.mopidy:
+    host: localhost
+```
+
+A `backend.music.mpd` is also provided, but if you use Mopidy instead of a bare MPD server then it's advised to use
+`backend.music.mopidy` instead - the former checks for updates by polling the server at regular intervals, while the
+Mopidy-specific backend listens for events continuously over the provided websocket interface.
+
+- Restart Platypush and head to `http://your-raspberry:8008`. You should see a new tab for Mopidy — yet another web
+  interface to interact with the server.
+
+![Platypush MPD interface](../img/mpd-1.png)
+
+Before proceeding on how to automate the interaction with your new music server, let's see how to turn Mopidy into a
+full multi-room music server with Snapcast.
+
+## Multi-room setup
+
+The ability to synchronize music across multiple rooms and devices is a great feature of a modern smart home. However,
+most of the commercial solutions available today (like Sonos or Bose) are expensive and require in most of the cases to
+replace your speakers with theirs. Luckily it’s relatively easy to set up a multi-room experience with multiple
+RaspberryPis, without having to change your speakers. Let’s see how.
+
+- Install Snapcast by following the instructions on their [Github page](https://github.com/badaix/snapcast)
+
+- Create an `/etc/default/snapserver` file on the machine(s) where you’re running your Mopidy instance(s) with the
+  following content:
+
+```yaml
+USER_OPTS="--user snapserver:snapserver --stream=pipe:///tmp/snapfifo?name=mopidy&codec=pcm --codec=pcm"
+SNAPSERVER_OPTS=""
+```
+
+In the example above we’ll use a PCM lossless codec for streaming the music, and we’ll be using `/tmp/snapfifo` as a
+file queue where Mopidy will push its audio stream.
+
+- Start snapserver on your Mopidy machine(s) by simply running the executable, and optionally add it to your startup
+  configuration.
+
+- Configure the [audio] section of your mopidy.conf file to stream to the Snapcast FIFO (note: with this configuration
+  Mopidy will only stream to the new file and not to your speakers, you'll need to run `snapclient` to play the audio):
+  
+```yaml
+[audio]
+mixer = software
+mixer_volume = 100
+output = audioconvert ! audio/x-raw,rate=48000,channels=2,format=S16LE ! wavenc ! filesink location=/tmp/snapfifo
+```
+
+The `audio.output` setting of Mopidy is actually a very flexible way of building GStreamer pipelines to redirect and
+transform the audio however you like. In this example I'm transforming the audio to stereo WAV at 48 kHz, which may be
+perfect if you're seeking for a true loseless audio experience, but may cause some glitches if your network isn't very
+stable (we're basically passing uncompressed audio around). It's possible to encode and compress the stream by applying
+e.g. an MP3 or OGG encoder to the pipeline, but this causes the GStreamer pipeline to become very unstable for some
+reason (the bug has been opened for a couple of years and Mopidy developers are still scratching their head on why it
+happens), so the loseless stream option may be the only one that works for now.
+
+- Create an `/etc/default/snapclient` file on all the machines that will be connecting to your Snapserver, included the
+  Mopidy machine itself if you want to directly play music from too (opposed to using it just as a music backend):
+  
+```yaml
+START_SNAPCLIENT=true
+USER_OPTS="--user snapclient:audio"
+```
+
+- Start `snapclient` on the machines that will be connecting to your Mopidy instance. The command will
+  be `snapclient -h localhost` on the machine that runs mopidy itself and `snapclient -h remote-host-ip-or-name` on the
+  other machines. You can run as many `snapclient` instances on a host as the servers you want to connect it to.
+
+- Enable the Snapcast backend and plugin in the Platypush configuration of each of the machines that will be running the
+  client or the server:
+
+```yaml
+backend.music.snapcast:
+    hosts:
+        - server1
+        - server2
+        - server3
+
+music.snapcast:
+    host: default-server-ip-or-name
+```
+
+- Restart Platypush and head to the web panel on port 8008. You should see a new tab for Snapcast, identified by the
+  speaker icon. From here you can control which stream will be playing on which host, you can create streaming groups,
+  change the volume etc.
+
+![Platypush Snapcast interface](../img/snapcast-1.png)
+
+- You can also install an [Android app](https://play.google.com/store/apps/details?id=de.badaix.snapcast) to control
+  your multi-room setup, even though the app allows you to control one server at the time. The app however will allow
+  you to play audio streams also on your smartphone.
+
+![Snapcast app interface](../img/snapcast-2.jpeg)
+
+If you use Iris as a web interface to Mopidy you can now head to settings and enable the Snapcast plugin. A speaker icon
+will appear in the bottom bar, and you’ll be able to control your music setup from there as well.
+
+Time to enjoy your low-cost but powerful multi-room music setup!