Generate separate snapshots for logical databases (#13792)

* Generate separate snapshots for sqlite, postgres and common
* Cleanup postgres dbs in the TRAP
* Say which logical DB we're applying updates to
* Run background updates on the state DB
* Add new option for accepting a SCHEMA_NUMBER

4 files changed, 140 insertions, 46 deletions

diff --git a/changelog.d/13792.misc b/changelog.d/13792.misc
new file mode 100644
index 0000000000..36ac91400a
--- /dev/null
+++ b/changelog.d/13792.misc
@@ -0,0 +1 @@
+Update the script which makes full schema dumps.
diff --git a/scripts-dev/make_full_schema.sh b/scripts-dev/make_full_schema.sh
index 61394360ce..d8cd06ee4f 100755
--- a/scripts-dev/make_full_schema.sh
+++ b/scripts-dev/make_full_schema.sh
@@ -2,23 +2,16 @@
 #
 # This script generates SQL files for creating a brand new Synapse DB with the latest
 # schema, on both SQLite3 and Postgres.
-#
-# It does so by having Synapse generate an up-to-date SQLite DB, then running
-# synapse_port_db to convert it to Postgres. It then dumps the contents of both.
 
 export PGHOST="localhost"
-POSTGRES_DB_NAME="synapse_full_schema.$$"
-
-SQLITE_SCHEMA_FILE="schema.sql.sqlite"
-SQLITE_ROWS_FILE="rows.sql.sqlite"
-POSTGRES_SCHEMA_FILE="full.sql.postgres"
-POSTGRES_ROWS_FILE="rows.sql.postgres"
-
+POSTGRES_MAIN_DB_NAME="synapse_full_schema_main.$$"
+POSTGRES_COMMON_DB_NAME="synapse_full_schema_common.$$"
+POSTGRES_STATE_DB_NAME="synapse_full_schema_state.$$"
 REQUIRED_DEPS=("matrix-synapse" "psycopg2")
 
 usage() {
   echo
-  echo "Usage: $0 -p <postgres_username> -o <path> [-c] [-n] [-h]"
+  echo "Usage: $0 -p <postgres_username> -o <path> [-c] [-n <schema number>] [-h]"
   echo
   echo "-p <postgres_username>"
   echo "  Username to connect to local postgres instance. The password will be requested"
@@ -27,11 +20,16 @@ usage() {
   echo "  CI mode. Prints every command that the script runs."
   echo "-o <path>"
   echo "  Directory to output full schema files to."
+  echo "-n <schema number>"
+  echo "  Schema number for the new snapshot. Used to set the location of files within "
+  echo "  the output directory, mimicking that of synapse/storage/schemas."
+  echo "  Defaults to 9999."
   echo "-h"
   echo "  Display this help text."
 }
 
-while getopts "p:co:h" opt; do
+SCHEMA_NUMBER="9999"
+while getopts "p:co:hn:" opt; do
   case $opt in
     p)
       export PGUSER=$OPTARG
@@ -48,6 +46,9 @@ while getopts "p:co:h" opt; do
       usage
       exit
       ;;
+    n)
+      SCHEMA_NUMBER="$OPTARG"
+      ;;
     \?)
       echo "ERROR: Invalid option: -$OPTARG" >&2
       usage
@@ -95,12 +96,21 @@ cd "$(dirname "$0")/.."
 TMPDIR=$(mktemp -d)
 KEY_FILE=$TMPDIR/test.signing.key # default Synapse signing key path
 SQLITE_CONFIG=$TMPDIR/sqlite.conf
-SQLITE_DB=$TMPDIR/homeserver.db
+SQLITE_MAIN_DB=$TMPDIR/main.db
+SQLITE_STATE_DB=$TMPDIR/state.db
+SQLITE_COMMON_DB=$TMPDIR/common.db
 POSTGRES_CONFIG=$TMPDIR/postgres.conf
 
 # Ensure these files are delete on script exit
-# TODO: the trap should also drop the temp postgres DB
-trap 'rm -rf $TMPDIR' EXIT
+cleanup() {
+  echo "Cleaning up temporary sqlite database and config files..."
+  rm -r "$TMPDIR"
+  echo "Cleaning up temporary Postgres database..."
+  dropdb --if-exists "$POSTGRES_COMMON_DB_NAME"
+  dropdb --if-exists "$POSTGRES_MAIN_DB_NAME"
+  dropdb --if-exists "$POSTGRES_STATE_DB_NAME"
+}
+trap 'cleanup' EXIT
 
 cat > "$SQLITE_CONFIG" <<EOF
 server_name: "test"
@@ -110,10 +120,22 @@ macaroon_secret_key: "abcde"
 
 report_stats: false
 
-database:
-  name: "sqlite3"
-  args:
-    database: "$SQLITE_DB"
+databases:
+  common:
+    name: "sqlite3"
+    data_stores: []
+    args:
+      database: "$SQLITE_COMMON_DB"
+  main:
+    name: "sqlite3"
+    data_stores: ["main"]
+    args:
+      database: "$SQLITE_MAIN_DB"
+  state:
+    name: "sqlite3"
+    data_stores: ["state"]
+    args:
+      database: "$SQLITE_STATE_DB"
 
 # Suppress the key server warning.
 trusted_key_servers: []
@@ -127,13 +149,32 @@ macaroon_secret_key: "abcde"
 
 report_stats: false
 
-database:
-  name: "psycopg2"
-  args:
-    user: "$PGUSER"
-    host: "$PGHOST"
-    password: "$PGPASSWORD"
-    database: "$POSTGRES_DB_NAME"
+databases:
+  common:
+    name: "psycopg2"
+    data_stores: []
+    args:
+      user: "$PGUSER"
+      host: "$PGHOST"
+      password: "$PGPASSWORD"
+      database: "$POSTGRES_COMMON_DB_NAME"
+  main:
+    name: "psycopg2"
+    data_stores: ["main"]
+    args:
+      user: "$PGUSER"
+      host: "$PGHOST"
+      password: "$PGPASSWORD"
+      database: "$POSTGRES_MAIN_DB_NAME"
+  state:
+    name: "psycopg2"
+    data_stores: ["state"]
+    args:
+      user: "$PGUSER"
+      host: "$PGHOST"
+      password: "$PGPASSWORD"
+      database: "$POSTGRES_STATE_DB_NAME"
+
 
 # Suppress the key server warning.
 trusted_key_servers: []
@@ -148,33 +189,76 @@ echo "Running db background jobs..."
 synapse/_scripts/update_synapse_database.py --database-config "$SQLITE_CONFIG" --run-background-updates
 
 # Create the PostgreSQL database.
-echo "Creating postgres database..."
-createdb --lc-collate=C --lc-ctype=C --template=template0 "$POSTGRES_DB_NAME"
+echo "Creating postgres databases..."
+createdb --lc-collate=C --lc-ctype=C --template=template0 "$POSTGRES_COMMON_DB_NAME"
+createdb --lc-collate=C --lc-ctype=C --template=template0 "$POSTGRES_MAIN_DB_NAME"
+createdb --lc-collate=C --lc-ctype=C --template=template0 "$POSTGRES_STATE_DB_NAME"
 
 echo "Running db background jobs..."
 synapse/_scripts/update_synapse_database.py --database-config "$POSTGRES_CONFIG" --run-background-updates
 
 
-# Delete schema_version, applied_schema_deltas and applied_module_schemas tables
-# Also delete any shadow tables from fts4
 echo "Dropping unwanted db tables..."
-SQL="
+
+# Some common tables are created and updated by Synapse itself and do not belong in the
+# schema.
+DROP_APP_MANAGED_TABLES="
 DROP TABLE schema_version;
+DROP TABLE schema_compat_version;
 DROP TABLE applied_schema_deltas;
 DROP TABLE applied_module_schemas;
 "
-sqlite3 "$SQLITE_DB" <<< "$SQL"
-psql "$POSTGRES_DB_NAME" -w <<< "$SQL"
+# Other common tables are not created by Synapse and do belong in the schema.
+# TODO: we could derive DROP_COMMON_TABLES from the dump of the common-only DB. But
+#       since there's only one table there, I haven't bothered to do so.
+DROP_COMMON_TABLES="$DROP_APP_MANAGED_TABLES
+DROP TABLE background_updates;
+"
+
+sqlite3 "$SQLITE_COMMON_DB" <<< "$DROP_APP_MANAGED_TABLES"
+sqlite3 "$SQLITE_MAIN_DB" <<< "$DROP_COMMON_TABLES"
+sqlite3 "$SQLITE_STATE_DB" <<< "$DROP_COMMON_TABLES"
+psql "$POSTGRES_COMMON_DB_NAME" -w <<< "$DROP_APP_MANAGED_TABLES"
+psql "$POSTGRES_MAIN_DB_NAME" -w <<< "$DROP_COMMON_TABLES"
+psql "$POSTGRES_STATE_DB_NAME" -w <<< "$DROP_COMMON_TABLES"
+
+# For Reasons(TM), SQLite's `.schema` also dumps out "shadow tables", the implementation
+# details behind full text search tables. Omit these from the dumps.
+
+sqlite3 "$SQLITE_MAIN_DB" <<< "
+DROP TABLE event_search_content;
+DROP TABLE event_search_segments;
+DROP TABLE event_search_segdir;
+DROP TABLE event_search_docsize;
+DROP TABLE event_search_stat;
+DROP TABLE user_directory_search_content;
+DROP TABLE user_directory_search_segments;
+DROP TABLE user_directory_search_segdir;
+DROP TABLE user_directory_search_docsize;
+DROP TABLE user_directory_search_stat;
+"
 
-echo "Dumping SQLite3 schema to '$OUTPUT_DIR/$SQLITE_SCHEMA_FILE' and '$OUTPUT_DIR/$SQLITE_ROWS_FILE'..."
-sqlite3 "$SQLITE_DB" ".schema --indent" > "$OUTPUT_DIR/$SQLITE_SCHEMA_FILE"
-sqlite3 "$SQLITE_DB" ".dump --data-only --nosys" > "$OUTPUT_DIR/$SQLITE_ROWS_FILE"
+echo "Dumping SQLite3 schema..."
+
+mkdir -p "$OUTPUT_DIR/"{common,main,state}"/full_schema/$SCHEMA_NUMBER"
+sqlite3 "$SQLITE_COMMON_DB" ".schema --indent"           > "$OUTPUT_DIR/common/full_schema/$SCHEMA_NUMBER/full.sql.sqlite"
+sqlite3 "$SQLITE_COMMON_DB" ".dump --data-only --nosys" >> "$OUTPUT_DIR/common/full_schema/$SCHEMA_NUMBER/full.sql.sqlite"
+sqlite3 "$SQLITE_MAIN_DB"   ".schema --indent"           > "$OUTPUT_DIR/main/full_schema/$SCHEMA_NUMBER/full.sql.sqlite"
+sqlite3 "$SQLITE_MAIN_DB"   ".dump --data-only --nosys" >> "$OUTPUT_DIR/main/full_schema/$SCHEMA_NUMBER/full.sql.sqlite"
+sqlite3 "$SQLITE_STATE_DB"  ".schema --indent"           > "$OUTPUT_DIR/state/full_schema/$SCHEMA_NUMBER/full.sql.sqlite"
+sqlite3 "$SQLITE_STATE_DB"  ".dump --data-only --nosys" >> "$OUTPUT_DIR/state/full_schema/$SCHEMA_NUMBER/full.sql.sqlite"
+
+cleanup_pg_schema() {
+   sed -e '/^$/d' -e '/^--/d' -e 's/public\.//g' -e '/^SET /d' -e '/^SELECT /d'
+}
 
-echo "Dumping Postgres schema to '$OUTPUT_DIR/$POSTGRES_SCHEMA_FILE' and '$OUTPUT_DIR/$POSTGRES_ROWS_FILE'..."
-pg_dump --format=plain --schema-only         --no-tablespaces --no-acl --no-owner "$POSTGRES_DB_NAME" | sed -e '/^$/d' -e '/^--/d' -e 's/public\.//g' -e '/^SET /d' -e '/^SELECT /d' > "$OUTPUT_DIR/$POSTGRES_SCHEMA_FILE"
-pg_dump --format=plain --data-only --inserts --no-tablespaces --no-acl --no-owner "$POSTGRES_DB_NAME" | sed -e '/^$/d' -e '/^--/d' -e 's/public\.//g' -e '/^SET /d' -e '/^SELECT /d' > "$OUTPUT_DIR/$POSTGRES_ROWS_FILE"
+echo "Dumping Postgres schema..."
 
-echo "Cleaning up temporary Postgres database..."
-dropdb $POSTGRES_DB_NAME
+pg_dump --format=plain --schema-only         --no-tablespaces --no-acl --no-owner "$POSTGRES_COMMON_DB_NAME" | cleanup_pg_schema  > "$OUTPUT_DIR/common/full_schema/$SCHEMA_NUMBER/full.sql.postgres"
+pg_dump --format=plain --data-only --inserts --no-tablespaces --no-acl --no-owner "$POSTGRES_COMMON_DB_NAME" | cleanup_pg_schema >> "$OUTPUT_DIR/common/full_schema/$SCHEMA_NUMBER/full.sql.postgres"
+pg_dump --format=plain --schema-only         --no-tablespaces --no-acl --no-owner "$POSTGRES_MAIN_DB_NAME"   | cleanup_pg_schema  > "$OUTPUT_DIR/main/full_schema/$SCHEMA_NUMBER/full.sql.postgres"
+pg_dump --format=plain --data-only --inserts --no-tablespaces --no-acl --no-owner "$POSTGRES_MAIN_DB_NAME"   | cleanup_pg_schema >> "$OUTPUT_DIR/main/full_schema/$SCHEMA_NUMBER/full.sql.postgres"
+pg_dump --format=plain --schema-only         --no-tablespaces --no-acl --no-owner "$POSTGRES_STATE_DB_NAME"  | cleanup_pg_schema  > "$OUTPUT_DIR/state/full_schema/$SCHEMA_NUMBER/full.sql.postgres"
+pg_dump --format=plain --data-only --inserts --no-tablespaces --no-acl --no-owner "$POSTGRES_STATE_DB_NAME"  | cleanup_pg_schema >> "$OUTPUT_DIR/state/full_schema/$SCHEMA_NUMBER/full.sql.postgres"
 
 echo "Done! Files dumped to: $OUTPUT_DIR"
diff --git a/synapse/_scripts/update_synapse_database.py b/synapse/_scripts/update_synapse_database.py
index b4aeae6dd5..fb1fb83f50 100755
--- a/synapse/_scripts/update_synapse_database.py
+++ b/synapse/_scripts/update_synapse_database.py
@@ -48,10 +48,13 @@ class MockHomeserver(HomeServer):
 
 
 def run_background_updates(hs: HomeServer) -> None:
-    store = hs.get_datastores().main
+    main = hs.get_datastores().main
+    state = hs.get_datastores().state
 
     async def run_background_updates() -> None:
-        await store.db_pool.updates.run_background_updates(sleep=False)
+        await main.db_pool.updates.run_background_updates(sleep=False)
+        if state:
+            await state.db_pool.updates.run_background_updates(sleep=False)
         # Stop the reactor to exit the script once every background update is run.
         reactor.stop()
 
@@ -97,8 +100,11 @@ def main() -> None:
     # Load, process and sanity-check the config.
     hs_config = yaml.safe_load(args.database_config)
 
-    if "database" not in hs_config:
-        sys.stderr.write("The configuration file must have a 'database' section.\n")
+    if "database" not in hs_config and "databases" not in hs_config:
+        sys.stderr.write(
+            "The configuration file must have a 'database' or 'databases' section. "
+            "See https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#database"
+        )
         sys.exit(4)
 
     config = HomeServerConfig()
diff --git a/synapse/storage/background_updates.py b/synapse/storage/background_updates.py
index bf5e7ee7be..2056ecb2c3 100644
--- a/synapse/storage/background_updates.py
+++ b/synapse/storage/background_updates.py
@@ -285,7 +285,10 @@ class BackgroundUpdater:
         back_to_back_failures = 0
 
         try:
-            logger.info("Starting background schema updates")
+            logger.info(
+                "Starting background schema updates for database %s",
+                self._database_name,
+            )
             while self.enabled:
                 try:
                     result = await self.do_next_background_update(sleep)