Using Postgres -------------- Set up database =============== The PostgreSQL database used *must* have the correct encoding set, otherwise would not be able to store UTF8 strings. To create a database with the correct encoding use, e.g.:: CREATE DATABASE synapse ENCODING 'UTF8' LC_COLLATE='C' LC_CTYPE='C' template=template0 OWNER synapse_user; This would create an appropriate database named ``synapse`` owned by the ``synapse_user`` user (which must already exist). Set up client in Debian/Ubuntu =========================== Postgres support depends on the postgres python connector ``psycopg2``. In the virtual env:: sudo apt-get install libpq-dev pip install psycopg2 Set up client in RHEL/CentOs 7 ============================== Make sure you have the appropriate version of postgres-devel installed. For a postgres 9.4, use the postgres 9.4 packages from [here](https://wiki.postgresql.org/wiki/YUM_Installation). As with Debian/Ubuntu, postgres support depends on the postgres python connector ``psycopg2``. In the virtual env:: sudo yum install postgresql-devel libpqxx-devel.x86_64 export PATH=/usr/pgsql-9.4/bin/:$PATH pip install psycopg2 Synapse config ============== When you are ready to start using PostgreSQL, add the following line to your config file:: database: name: psycopg2 args: user: <user> password: <pass> database: <db> host: <host> cp_min: 5 cp_max: 10 All key, values in ``args`` are passed to the ``psycopg2.connect(..)`` function, except keys beginning with ``cp_``, which are consumed by the twisted adbapi connection pool. Porting from SQLite =================== Overview ~~~~~~~~ The script ``synapse_port_db`` allows porting an existing synapse server backed by SQLite to using PostgreSQL. This is done in as a two phase process: 1. Copy the existing SQLite database to a separate location (while the server is down) and running the port script against that offline database. 2. Shut down the server. Rerun the port script to port any data that has come in since taking the first snapshot. Restart server against the PostgreSQL database. The port script is designed to be run repeatedly against newer snapshots of the SQLite database file. This makes it safe to repeat step 1 if there was a delay between taking the previous snapshot and being ready to do step 2. It is safe to at any time kill the port script and restart it. Using the port script ~~~~~~~~~~~~~~~~~~~~~ Firstly, shut down the currently running synapse server and copy its database file (typically ``homeserver.db``) to another location. Once the copy is complete, restart synapse. For instance:: ./synctl stop cp homeserver.db homeserver.db.snapshot ./synctl start Assuming your new config file (as described in the section *Synapse config*) is named ``homeserver-postgres.yaml`` and the SQLite snapshot is at ``homeserver.db.snapshot`` then simply run:: synapse_port_db --sqlite-database homeserver.db.snapshot \ --postgres-config homeserver-postgres.yaml The flag ``--curses`` displays a coloured curses progress UI. If the script took a long time to complete, or time has otherwise passed since the original snapshot was taken, repeat the previous steps with a newer snapshot. To complete the conversion shut down the synapse server and run the port script one last time, e.g. if the SQLite database is at ``homeserver.db`` run:: synapse_port_db --sqlite-database homeserver.db \ --postgres-config database_config.yaml Once that has completed, change the synapse config to point at the PostgreSQL database configuration file using the ``database_config`` parameter (see `Synapse Config`_) and restart synapse. Synapse should now be running against PostgreSQL.