synapse/docs/postgres.rst

115 lines
3.4 KiB
ReStructuredText
Raw Normal View History

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
=============
2015-04-29 01:48:07 +02:00
Postgres support depends on the postgres python connector ``psycopg2``. In the
virtual env::
sudo apt-get install libpq-dev
pip install psycopg2
Synapse config
==============
2015-04-29 01:48:07 +02:00
When you are ready to start using PostgreSQL, add the following line to your
config file::
database_config: <db_config_file>
Where ``<db_config_file>`` is the file name that points to a yaml file of the
following form::
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
===================
2015-04-29 01:48:07 +02:00
Overview
~~~~~~~~
The script ``port_from_sqlite_to_postgres.py`` 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
2015-04-29 01:48:07 +02:00
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
2015-04-29 01:48:07 +02:00
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
2015-04-29 01:48:07 +02:00
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 database config file (as described in the section *Synapse
config*) is named ``database_config.yaml`` and the SQLite snapshot is at
``homeserver.db.snapshot`` then simply run::
python scripts/port_from_sqlite_to_postgres.py \
--sqlite-database homeserver.db.snapshot \
--postgres-config database_config.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
2015-04-28 19:09:20 +02:00
script one last time, e.g. if the SQLite database is at ``homeserver.db``
run::
python scripts/port_from_sqlite_to_postgres.py \
--sqlite-database homeserver.db \
--postgres-config database_config.yaml
Once that has completed, change the synapse config to point at the PostgreSQL
2015-04-29 01:48:07 +02:00
database configuration file using the ``database_config`` parameter (see
`Synapse Config`_) and restart synapse. Synapse should now be running against
PostgreSQL.