add postgres service for backend database

.env.example

@@ -1,4 +1,5 @@
-IMAGE_TAG=latest
+# synapse
+SYNAPSE_IMAGE_TAG=latest
 SERVER_NAME=localhost
 HTTP_PORT=8008
 CONFIG_DIR=/data
@@ -6,3 +7,5 @@ CONFIG_FILE_NAME=homeserver.yaml
 UID=991
 GID=991
 TZ=UTC
+
+POSTGRESQL_IMAGE_TAG=14

.gitignore

@@ -1 +1,2 @@
 .env
+postgres_password.txt

docker-compose.yaml

@@ -1,9 +1,27 @@
 volumes:
   synapse-data:
+  postgres:
+
+secrets:
+  postgres_password:
+    file: ./postgres_password.txt
 
 services:
+  postgres:
+      image: postgres:${POSTGRESQL_IMAGE_TAG}
+      restart: unless-stopped
+      volumes:
+        - postgres:/var/lib/postgresql/data:rw
+      secrets:
+        - postgres_password
+      environment:
+        POSTGRES_DB: synapse
+        POSTGRES_USER: synapse_user
+        POSTGRES_PASSWORD_FILE: /run/secrets/postgres_password
+        POSTGRES_INITDB_ARGS: --encoding=UTF8 --locale=C
+
   synapse:
-    image: matrixdotorg/synapse:${IMAGE_TAG}
+    image: matrixdotorg/synapse:${SYNAPSE_IMAGE_TAG}
     restart: unless-stopped
     volumes:
       - synapse-data:${CONFIG_DIR}
@@ -15,3 +33,5 @@ services:
       TZ: ${TZ}
     ports:
       - ${HTTP_PORT}:8008
+    depends_on:
+      - postgres