Introduction

Matrix is an ambitious new ecosystem for open federated Instant Messaging and VoIP. The basics you need to know to get up and running are:

• Everything in Matrix happens in a room. Rooms are distributed and do not exist on any single server. Rooms can be located using convenience aliases like #matrix:matrix.org or #test:localhost:8008.
• Matrix user IDs look like @matthew:matrix.org (although in the future you will normally refer to yourself and others using a 3PID: email address, phone number, etc rather than manipulating Matrix user IDs)

The overall architecture is:

client <----> homeserver <=====================> homeserver <----> client
       https://somewhere.org/_matrix      https://elsewhere.net/_matrix

#matrix:matrix.org is the official support room for Matrix, and can be accessed by the web client at http://matrix.org/alpha or via an IRC bridge at irc://irc.freenode.net/matrix.

Synapse is currently in rapid development, but as of version 0.5 we believe it is sufficiently stable to be run as an internet-facing service for real usage!

About Matrix

Matrix specifies a set of pragmatic RESTful HTTP JSON APIs as an open standard, which handle:

• Creating and managing fully distributed chat rooms with no single points of control or failure
• Eventually-consistent cryptographically secure synchronisation of room state across a global open network of federated servers and services
• Sending and receiving extensible messages in a room with (optional) end-to-end encryption[1]
• Inviting, joining, leaving, kicking, banning room members
• Managing user accounts (registration, login, logout)
• Using 3rd Party IDs (3PIDs) such as email addresses, phone numbers, Facebook accounts to authenticate, identify and discover users on Matrix.
• Placing 1:1 VoIP and Video calls

These APIs are intended to be implemented on a wide range of servers, services and clients, letting developers build messaging and VoIP functionality on top of the entirely open Matrix ecosystem rather than using closed or proprietary solutions. The hope is for Matrix to act as the building blocks for a new generation of fully open and interoperable messaging and VoIP apps for the internet.

Synapse is a reference "homeserver" implementation of Matrix from the core development team at matrix.org, written in Python/Twisted for clarity and simplicity. It is intended to showcase the concept of Matrix and let folks see the spec in the context of a codebase and let you run your own homeserver and generally help bootstrap the ecosystem.

In Matrix, every user runs one or more Matrix clients, which connect through to a Matrix homeserver which stores all their personal chat history and user account information - much as a mail client connects through to an IMAP/SMTP server. Just like email, you can either run your own Matrix homeserver and control and own your own communications and history or use one hosted by someone else (e.g. matrix.org) - there is no single point of control or mandatory service provider in Matrix, unlike WhatsApp, Facebook, Hangouts, etc.

Synapse ships with two basic demo Matrix clients: webclient (a basic group chat web client demo implemented in AngularJS) and cmdclient (a basic Python command line utility which lets you easily see what the JSON APIs are up to).

Meanwhile, iOS and Android SDKs and clients are currently in development and available from:

• https://github.com/matrix-org/matrix-ios-sdk
• https://github.com/matrix-org/matrix-android-sdk

We'd like to invite you to join #matrix:matrix.org (via http://matrix.org/alpha), run a homeserver, take a look at the Matrix spec at http://matrix.org/docs/spec, experiment with the APIs and the demo clients, and report any bugs via http://matrix.org/jira.

Thanks for using Matrix!

[1] End-to-end encryption is currently in development

Homeserver Installation

System requirements: - POSIX-compliant system (tested on Linux & OSX) - Python 2.7

Synapse is written in python but some of the libraries is uses are written in C. So before we can install synapse itself we need a working C compiler and the header files for python C extensions.

Installing prerequisites on Ubuntu or Debian:

$ sudo apt-get install build-essential python2.7-dev libffi-dev \
                       python-pip python-setuptools sqlite3 \
                       libssl-dev python-virtualenv libjpeg-dev

Installing prerequisites on Mac OS X:

$ xcode-select --install

To install the synapse homeserver run:

$ virutalenv ~/.synapse
$ source ~/.synapse/bin/activate
$ pip install --process-dependency-links https://github.com/matrix-org/synapse/tarball/master

This installs synapse, along with the libraries it uses, into a virtual environment under synapse.

For reliable VoIP calls to be routed via this homeserver, you MUST configure a TURN server. See docs/turn-howto.rst for details.

Troubleshooting Installation

Synapse requires pip 1.7 or later, so if your OS provides too old a version and you get errors about error: no such option: --process-dependency-links you may need to manually upgrade it:

$ sudo pip install --upgrade pip

If pip crashes mid-installation for reason (e.g. lost terminal), pip may refuse to run until you remove the temporary installation directory it created. To reset the installation:

$ rm -rf /tmp/pip_install_matrix

pip seems to leak lots of memory during installation. For instance, a Linux host with 512MB of RAM may run out of memory whilst installing Twisted. If this happens, you will have to individually install the dependencies which are failing, e.g.:

$ pip install twisted

On OSX, if you encounter clang: error: unknown argument: '-mno-fused-madd' you will need to export CFLAGS=-Qunused-arguments.

Windows Install

Synapse can be installed on Cygwin. It requires the following Cygwin packages:

• gcc
• git
• libffi-devel
• openssl (and openssl-devel, python-openssl)
• python
• python-setuptools

The content repository requires additional packages and will be unable to process uploads without them:

• libjpeg8
• libjpeg8-devel
• zlib

If you choose to install Synapse without these packages, you will need to reinstall pillow for changes to be applied, e.g. pip uninstall pillow pip install pillow --user

Troubleshooting:

• You may need to upgrade setuptools to get this to work correctly: pip install setuptools --upgrade.
• You may encounter errors indicating that ffi.h is missing, even with libffi-devel installed. If you do, copy the .h files: cp /usr/lib/libffi-3.0.13/include/*.h /usr/include
• You may need to install libsodium from source in order to install PyNacl. If you do, you may need to create a symlink to libsodium.a so ld can find it: ln -s /usr/local/lib/libsodium.a /usr/lib/libsodium.a

Running Your Homeserver

To actually run your new homeserver, pick a working directory for Synapse to run (e.g. ~/.synapse), and:

$ cd ~/.synapse
$ source ./bin/activate
$ synctl start

Troubleshooting Running

If synapse fails with missing "sodium.h" crypto errors, you may need to manually upgrade PyNaCL, as synapse uses NaCl (http://nacl.cr.yp.to/) for encryption and digital signatures. Unfortunately PyNACL currently has a few issues (pyca/pynacl#53) and (pyca/pynacl#79) that mean it may not install correctly, causing all tests to fail with errors about missing "sodium.h". To fix try re-installing from PyPI or directly from (https://github.com/pyca/pynacl):

$ # Install from PyPI
$ pip install --user --upgrade --force pynacl
$ # Install from github
$ pip install --user https://github.com/pyca/pynacl/tarball/master

Homeserver Development

To check out a homeserver for development, clone the git repo into a working directory of your choice:

$ git clone https://github.com/matrix-org/synapse.git
$ cd synapse

The homeserver has a number of external dependencies, that are easiest to install using pip and a virtualenv:

$ virtualenv env
$ source env/bin/activate
$ python synapse/dependencies | xargs -i pip install
$ pip install setuptools_trial mock

This will run a process of downloading and installing all the needed dependencies into a virtual env.

Once this is done, you may wish to run the homeserver's unit tests, to check that everything is installed as it should be:

$ python setup.py test

This should end with a 'PASSED' result:

Ran 143 tests in 0.601s

PASSED (successes=143)

Upgrading an existing homeserver

IMPORTANT: Before upgrading an existing homeserver to a new version, please refer to UPGRADE.rst for any additional instructions.

Otherwise, simply re-install the new codebase over the current one - e.g. by pip install --process-dependency-links https://github.com/matrix-org/synapse/tarball/master if using pip, or by git pull if running off a git working copy.

Setting up Federation

In order for other homeservers to send messages to your server, it will need to be publicly visible on the internet, and they will need to know its host name. You have two choices here, which will influence the form of your Matrix user IDs:

1. Use the machine's own hostname as available on public DNS in the form of its A or AAAA records. This is easier to set up initially, perhaps for testing, but lacks the flexibility of SRV.
2. Set up a SRV record for your domain name. This requires you create a SRV record in DNS, but gives the flexibility to run the server on your own choice of TCP port, on a machine that might not be the same name as the domain name.

For the first form, simply pass the required hostname (of the machine) as the --server-name parameter:

$ python -m synapse.app.homeserver \
    --server-name machine.my.domain.name \
    --config-path homeserver.config \
    --generate-config
$ python -m synapse.app.homeserver --config-path homeserver.config

Alternatively, you can run synctl start to guide you through the process.

For the second form, first create your SRV record and publish it in DNS. This needs to be named _matrix._tcp.YOURDOMAIN, and point at at least one hostname and port where the server is running. (At the current time synapse does not support clustering multiple servers into a single logical homeserver). The DNS record would then look something like:

$ dig -t srv _matrix._tcp.machine.my.domaine.name
_matrix._tcp    IN      SRV     10 0 8448 machine.my.domain.name.

At this point, you should then run the homeserver with the hostname of this SRV record, as that is the name other machines will expect it to have:

$ python -m synapse.app.homeserver \
    --server-name YOURDOMAIN \
    --bind-port 8448 \
    --config-path homeserver.config \
    --generate-config
$ python -m synapse.app.homeserver --config-path homeserver.config

You may additionally want to pass one or more "-v" options, in order to increase the verbosity of logging output; at least for initial testing.

For the initial alpha release, the homeserver is not speaking TLS for either client-server or server-server traffic for ease of debugging. We have also not spent any time yet getting the homeserver to run behind loadbalancers.

Running a Demo Federation of Homeservers

If you want to get up and running quickly with a trio of homeservers in a private federation (localhost:8080, localhost:8081 and localhost:8082) which you can then access through the webclient running at http://localhost:8080. Simply run:

$ demo/start.sh

This is mainly useful just for development purposes.

Running The Demo Web Client

The homeserver runs a web client by default at https://localhost:8448/.

If this is the first time you have used the client from that browser (it uses HTML5 local storage to remember its config), you will need to log in to your account. If you don't yet have an account, because you've just started the homeserver for the first time, then you'll need to register one.

Registering A New Account

Your new user name will be formed partly from the hostname your server is running as, and partly from a localpart you specify when you create the account. Your name will take the form of:

@localpart:my.domain.here
     (pronounced "at localpart on my dot domain dot here")

Specify your desired localpart in the topmost box of the "Register for an account" form, and click the "Register" button. Hostnames can contain ports if required due to lack of SRV records (e.g. @matthew:localhost:8448 on an internal synapse sandbox running on localhost)

Logging In To An Existing Account

Just enter the @localpart:my.domain.here Matrix user ID and password into the form and click the Login button.

Identity Servers

The job of authenticating 3PIDs and tracking which 3PIDs are associated with a given Matrix user is very security-sensitive, as there is obvious risk of spam if it is too easy to sign up for Matrix accounts or harvest 3PID data. Meanwhile the job of publishing the end-to-end encryption public keys for Matrix users is also very security-sensitive for similar reasons.

Therefore the role of managing trusted identity in the Matrix ecosystem is farmed out to a cluster of known trusted ecosystem partners, who run 'Matrix Identity Servers' such as sydent, whose role is purely to authenticate and track 3PID logins and publish end-user public keys.

It's currently early days for identity servers as Matrix is not yet using 3PIDs as the primary means of identity and E2E encryption is not complete. As such, we are running a single identity server (http://matrix.org:8090) at the current time.

Where's the spec?!

The source of the matrix spec lives at https://github.com/matrix-org/matrix-doc. A recent HTML snapshot of this lives at http://matrix.org/docs/spec

Building Internal API Documentation

Before building internal API documentation install sphinx and sphinxcontrib-napoleon:

$ pip install sphinx
$ pip install sphinxcontrib-napoleon

Building internal API documentation:

$ python setup.py build_sphinx