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    .. contents::
    
    
    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:8448``.
    
    
    - Matrix user IDs look like ``@matthew:matrix.org`` (although in the future
    
      you will normally refer to yourself and others using a third party identifier
    
      (3PID): email address, phone number, etc rather than manipulating Matrix user IDs)
    
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    The overall architecture is::
    
    
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          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
    
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    accessed by any client from https://matrix.org/docs/projects/try-matrix-now or
    via 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!
    
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    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. The homeserver 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
    
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    command line utility which lets you easily see what the JSON APIs are up to).
    
    Meanwhile, iOS and Android SDKs and clients are available from:
    
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    - https://github.com/matrix-org/matrix-ios-sdk
    
    - https://github.com/matrix-org/matrix-ios-kit
    - https://github.com/matrix-org/matrix-ios-console
    
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    - https://github.com/matrix-org/matrix-android-sdk
    
    We'd like to invite you to join #matrix:matrix.org (via
    
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    https://matrix.org/docs/projects/try-matrix-now), run a homeserver, take a look
    at the Matrix spec at https://matrix.org/docs/spec and API docs at
    
    https://matrix.org/docs/api, experiment with the APIs and the demo clients, and
    
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    report any bugs via github.
    
    [1] End-to-end encryption is currently in beta.
    
    Synapse Installation
    ====================
    
    Synapse is the reference python/twisted Matrix homeserver implementation.
    
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    - POSIX-compliant system (tested on Linux & OS X)
    
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    - At least 1GB of free RAM if you want to join large public rooms like #matrix:matrix.org
    
    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 \
    
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                             libssl-dev python-virtualenv libjpeg-dev libxslt1-dev
    
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    Installing prerequisites on ArchLinux::
    
    
        sudo pacman -S base-devel python2 python-pip \
                       python-setuptools python-virtualenv sqlite3
    
    Installing prerequisites on CentOS 7::
    
        sudo yum install libtiff-devel libjpeg-devel libzip-devel freetype-devel \
                         lcms2-devel libwebp-devel tcl-devel tk-devel \
    
                         python-virtualenv libffi-devel openssl-devel
    
    Installing prerequisites on Mac OS X::
    
        xcode-select --install
        sudo easy_install pip
        sudo pip install virtualenv
    
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    Installing prerequisites on Raspbian::
    
        sudo apt-get install build-essential python2.7-dev libffi-dev \
                             python-pip python-setuptools sqlite3 \
                             libssl-dev python-virtualenv libjpeg-dev
        sudo pip install --upgrade pip
        sudo pip install --upgrade ndg-httpsclient
        sudo pip install --upgrade virtualenv
    
    
    Installing prerequisites on openSUSE::
    
        sudo zypper in -t pattern devel_basis
        sudo zypper in python-pip python-setuptools sqlite3 python-virtualenv \
                       python-devel libffi-devel libopenssl-devel libjpeg62-devel
    
    
    To install the synapse homeserver run::
    
    
        virtualenv -p python2.7 ~/.synapse
        source ~/.synapse/bin/activate
    
        pip install https://github.com/matrix-org/synapse/tarball/master
    
    This installs synapse, along with the libraries it uses, into a virtual
    
    environment under ``~/.synapse``.  Feel free to pick a different directory
    if you prefer.
    
    
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    In case of problems, please see the _`Troubleshooting` section below.
    
    Alternatively, Silvio Fricke has contributed a Dockerfile to automate the
    above in Docker at https://registry.hub.docker.com/u/silviof/docker-matrix/.
    
    
    Also, Martin Giess has created an auto-deployment process with vagrant/ansible,
    tested with VirtualBox/AWS/DigitalOcean - see https://github.com/EMnify/matrix-synapse-auto-deploy
    
    To set up your homeserver, run (in your virtualenv, as before)::
    
    
            --server-name machine.my.domain.name \
    
    ...substituting your host and domain name as appropriate.
    
    This will generate you a config file that you can then customise, but it will
    also generate a set of keys for you. These keys will allow your Home Server to
    identify itself to other Home Servers, so don't lose or delete them. It would be
    wise to back them up somewhere safe. If, for whatever reason, you do need to
    change your Home Server's keys, you may find that other Home Servers have the
    old key cached. If you update the signing key, you should change the name of the
    
    key in the <server name>.signing.key file (the second word) to something different.
    
    By default, registration of new users is disabled. You can either enable
    
    registration in the config by specifying ``enable_registration: true`` (it is
    then recommended to also set up CAPTCHA - see `<docs/CAPTCHA_SETUP.rst>`_), or
    
    you can use the command line to register new users::
    
        $ source ~/.synapse/bin/activate
    
        $ register_new_matrix_user -c homeserver.yaml https://localhost:8448
        New user localpart: erikj
        Password:
        Confirm password:
        Success!
    
    
    For reliable VoIP calls to be routed via this homeserver, you MUST configure
    
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    a TURN server.  See `<docs/turn-howto.rst>`_ for details.
    
    Running Synapse
    ===============
    
    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
    
    
    
    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).
    
    If registration fails, you may need to enable it in the homeserver (see
    `Synapse Installation`_ above)
    
    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.
    
    
    
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    Matrix serves raw user generated data in some APIs - specifically the `content
    repository endpoints <http://matrix.org/docs/spec/client_server/latest.html#get-matrix-media-r0-download-servername-mediaid>`_.
    
    
    Whilst we have tried to mitigate against possible XSS attacks (e.g.
    https://github.com/matrix-org/synapse/pull/1021) we recommend running
    matrix homeservers on a dedicated domain name, to limit any malicious user generated
    content served to web browsers a matrix API from being able to attack webapps hosted
    on the same domain.  This is particularly true of sharing a matrix webclient and
    server on the same domain.
    
    See https://github.com/vector-im/vector-web/issues/1977 and
    https://developer.github.com/changes/2014-04-25-user-content-security for more details.
    
    
    Platform Specific Instructions
    ==============================
    
    Debian
    ------
    
    Matrix provides official Debian packages via apt from http://matrix.org/packages/debian/.
    Note that these packages do not include a client - choose one from
    
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    https://matrix.org/docs/projects/try-matrix-now/ (or build your own with one of our SDKs :)
    
    
    Fedora
    ------
    
    Oleg Girko provides Fedora RPMs at
    https://obs.infoserver.lv/project/monitor/matrix-synapse
    
    
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    ArchLinux
    
    The quickest way to get up and running with ArchLinux is probably with Ivan
    Shapovalov's AUR package from
    https://aur.archlinux.org/packages/matrix-synapse/, which should pull in all
    the necessary dependencies.
    
    Alternatively, to install using pip a few changes may be needed as ArchLinux
    defaults to python 3, but synapse currently assumes python 2.7 by default:
    
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    pip may be outdated (6.0.7-1 and needs to be upgraded to 6.0.8-1 )::
    
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    You also may need to explicitly specify python 2.7 again during the install
    request::
    
    
        pip2.7 install https://github.com/matrix-org/synapse/tarball/master
    
    If you encounter an error with lib bcrypt causing an Wrong ELF Class:
    ELFCLASS32 (x64 Systems), you may need to reinstall py-bcrypt to correctly
    compile it under the right architecture. (This should not be needed if
    installing under virtualenv)::
    
    
        sudo pip2.7 uninstall py-bcrypt
        sudo pip2.7 install py-bcrypt
    
    During setup of Synapse you need to call python2.7 directly again::
    
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          --server-name machine.my.domain.name \
          --config-path homeserver.yaml \
          --generate-config
    
    ...substituting your host and domain name as appropriate.
    
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    Synapse can be installed via FreeBSD Ports or Packages contributed by Brendan Molloy from:
    
    
     - Ports: ``cd /usr/ports/net/py-matrix-synapse && make install clean``
     - Packages: ``pkg install py27-matrix-synapse``
    
    
    NixOS
    -----
    
    Robin Lambertz has packaged Synapse for NixOS at:
    https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/services/misc/matrix-synapse.nix
    
    
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    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
    
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    The content repository requires additional packages and will be unable to process
    uploads without them:
    
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    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``
    
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    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``
    
    
    Troubleshooting Installation
    ----------------------------
    
    Synapse requires pip 1.7 or later, so if your OS provides too old a version you
    
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    Installing may fail with ``Could not find any downloads that satisfy the requirement pymacaroons-pynacl (from matrix-synapse==0.12.0)``.
    You can fix this by manually upgrading pip and virtualenv::
    
        sudo pip install --upgrade virtualenv
    
    You can next rerun ``virtualenv -p python2.7 synapse`` to update the virtual env.
    
    Installing may fail during installing virtualenv with ``InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.``
    You can fix this  by manually installing ndg-httpsclient::
    
        pip install --upgrade ndg-httpsclient
    
    
    Installing may fail with ``mock requires setuptools>=17.1. Aborting installation``.
    You can fix this by upgrading setuptools::
    
        pip install --upgrade setuptools
    
    
    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::
    
    
    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
    
    On OS X, if you encounter clang: error: unknown argument: '-mno-fused-madd' you
    
    will need to export CFLAGS=-Qunused-arguments.
    
    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
    
    (https://github.com/pyca/pynacl/issues/53) and
    (https://github.com/pyca/pynacl/issues/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
    
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    ArchLinux
    
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    If running `$ synctl start` fails with 'returned non-zero exit status 1',
    you will need to explicitly call Python2.7 - either running as::
    
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        python2.7 -m synapse.app.homeserver --daemonize -c homeserver.yaml
    
    ...or by editing synctl with the correct python executable.
    
    Upgrading an existing Synapse
    =============================
    
    The instructions for upgrading synapse are in `UPGRADE.rst`_.
    Please check these instructions as upgrading may require extra steps for some
    versions of synapse.
    
    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
    
    1) Use the machine's own hostname as available on public DNS in the form of
    
       its A 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.
    
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    For the first form, simply pass the required hostname (of the machine) as the
    
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    --server-name parameter::
    
            --server-name machine.my.domain.name \
    
        python -m synapse.app.homeserver --config-path homeserver.yaml
    
    Alternatively, you can run ``synctl start`` to guide you through the process.
    
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    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::
    
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        $ dig -t srv _matrix._tcp.machine.my.domain.name
    
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        _matrix._tcp    IN      SRV     10 0 8448 machine.my.domain.name.
    
    
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    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 --config-path homeserver.yaml
    
    If you've already generated the config file, you need to edit the "server_name"
    in you  ```homeserver.yaml``` file. If you've already started Synapse and a
    database has been created, you will have to recreate the database.
    
    
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    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.
    
    
    Running a Demo Federation of Synapses
    -------------------------------------
    
    
    If you want to get up and running quickly with a trio of homeservers in a
    private federation (``localhost:8080``, ``localhost:8081`` and
    
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    ``localhost:8082``) which you can then access through the webclient running at
    http://localhost:8080. Simply run::
    
    This is mainly useful just for development purposes.
    
    Using PostgreSQL
    ================
    
    As of Synapse 0.9, `PostgreSQL <http://www.postgresql.org>`_ is supported as an
    alternative to the `SQLite <http://sqlite.org/>`_ database that Synapse has
    traditionally used for convenience and simplicity.
    
    The advantages of Postgres include:
    
    * significant performance improvements due to the superior threading and
      caching model, smarter query optimiser
    * allowing the DB to be run on separate hardware
    * allowing basic active/backup high-availability with a "hot spare" synapse
      pointing at the same DB master, as well as enabling DB replication in
      synapse itself.
    
    For information on how to install and use PostgreSQL, please see
    `docs/postgres.rst <docs/postgres.rst>`_.
    
    
    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 (https://matrix.org) at the current
    
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    time.
    
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    URL Previews
    ============
    
    
    Synapse 0.15.0 introduces a new API for previewing URLs at
    ``/_matrix/media/r0/preview_url``.  This is disabled by default.  To turn it on
    you must enable the ``url_preview_enabled: True`` config parameter and
    explicitly specify the IP ranges that Synapse is not allowed to spider for
    previewing in the ``url_preview_ip_range_blacklist`` configuration parameter.
    This is critical from a security perspective to stop arbitrary Matrix users
    spidering 'internal' URLs on your network.  At the very least we recommend that
    your loopback and RFC1918 IP addresses are blacklisted.
    
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    This also requires the optional lxml and netaddr python dependencies to be
    installed.
    
    
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    Password reset
    ==============
    
    If a user has registered an email address to their account using an identity
    server, they can request a password-reset token via clients such as Vector.
    
    A manual password reset can be done via direct database access as follows.
    
    
    First calculate the hash of the new password::
    
    
        $ source ~/.synapse/bin/activate
        $ ./scripts/hash_password
    
        Password:
        Confirm password:
    
        $2a$12$xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    
    
    Then update the `users` table in the database::
    
    
        UPDATE users SET password_hash='$2a$12$xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'
            WHERE name='@test:test.com';
    
    
    Synapse Development
    ===================
    
    To check out a synapse for development, clone the git repo into a working
    directory of your choice::
    
        git clone https://github.com/matrix-org/synapse.git
        cd synapse
    
    Synapse has a number of external dependencies, that are easiest
    to install using pip and a virtualenv::
    
        virtualenv env
        source env/bin/activate
        python synapse/python_dependencies.py | xargs -n1 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 Synapse'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)
    
    
    
    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::
    
    Help!! Synapse eats all my RAM!
    
    ===============================
    
    Synapse's architecture is quite RAM hungry currently - we deliberately
    cache a lot of recent room data and metadata in RAM in order to speed up
    common requests.  We'll improve this in future, but for now the easiest
    way to either reduce the RAM usage (at the risk of slowing things down)
    is to set the almost-undocumented ``SYNAPSE_CACHE_FACTOR`` environment
    variable.  Roughly speaking, a SYNAPSE_CACHE_FACTOR of 1.0 will max out
    at around 3-4GB of resident memory - this is what we currently run the
    matrix.org on.  The default setting is currently 0.1, which is probably
    around a ~700MB footprint.  You can dial it down further to 0.02 if
    desired, which targets roughly ~512MB.  Conversely you can dial it up if
    you need performance for lots of users and have a box with a lot of RAM.