Purge History API

The purge history API allows server admins to purge historic events from their +database, reclaiming disk space.

Depending on the amount of history being purged a call to the API may take +several minutes or longer. During this period users will not be able to +paginate further back in the room from the point being purged from.

Note that Synapse requires at least one message in each room, so it will never +delete the last message in a room.

The API is:

POST /_synapse/admin/v1/purge_history/<room_id>[/<event_id>]
+

To use it, you will need to authenticate by providing an access_token for a +server admin: Admin API

By default, events sent by local users are not deleted, as they may represent +the only copies of this content in existence. (Events sent by remote users are +deleted.)

Room state data (such as joins, leaves, topic) is always preserved.

To delete local message events as well, set delete_local_events in the body:

{
+   "delete_local_events": true
+}
+

The caller must specify the point in the room to purge up to. This can be +specified by including an event_id in the URI, or by setting a +purge_up_to_event_id or purge_up_to_ts in the request body. If an event +id is given, that event (and others at the same graph depth) will be retained. +If purge_up_to_ts is given, it should be a timestamp since the unix epoch, +in milliseconds.

The API starts the purge running, and returns immediately with a JSON body with +a purge id:

{
+    "purge_id": "<opaque id>"
+}
+

Purge status query

It is possible to poll for updates on recent purges with a second API;

GET /_synapse/admin/v1/purge_history_status/<purge_id>
+

Again, you will need to authenticate by providing an access_token for a +server admin.

This API returns a JSON body like the following:

{
+    "status": "active"
+}
+

The status will be one of active, complete, or failed.

Reclaim disk space (Postgres)

To reclaim the disk space and return it to the operating system, you need to run +VACUUM FULL; on the database.

https://www.postgresql.org/docs/current/sql-vacuum.html

+ +