Allow ':memory:' as the database path for sqlite3

synapse/app/homeserver.py

@@ -247,7 +247,13 @@ def setup():
 
     logger.info("Database prepared in %s.", db_name)
 
-    hs.get_db_pool()
+    db_pool = hs.get_db_pool()
+
+    if db_name == ":memory:"
+        # Memory databases will need to be setup each time they are opened.
+        reactor.callWhenRunning(
+            hs.get_db_pool().runWithConnection, prepare_database
+        )
 
     if config.manhole:
         f = twisted.manhole.telnet.ShellFactory()

synapse/config/database.py

@@ -20,6 +20,9 @@ import os
 class DatabaseConfig(Config):
     def __init__(self, args):
         super(DatabaseConfig, self).__init__(args)
+        if args.database_path == ":memory:":
+            self.database_path = ":memory:"
+        else:
             self.database_path = self.abspath(args.database_path)
 
     @classmethod