Add named pgdata volume that persists on down/up

This allows to restore after `docker-compose down` without
reuploading database and rerunning migrations.

Need to explicitly remove the volume to recreate DB from
scratch `docker volume rm warehouse_pgdata`.

Author: abitrolly

Makefile

@@ -155,6 +155,7 @@ endif
 
 resetdb:
 	docker-compose rm --stop --force db
+	docker volume rm warehouse_pgdata
 	docker-compose up -d db
 
 initdb:

docker-compose.yml

@@ -2,6 +2,7 @@ version: '3'
 
 volumes:
   packages:
+  pgdata:
   sponsorlogos:
   vault:
 
@@ -32,6 +33,7 @@ services:
       POSTGRES_DB: warehouse
       POSTGRES_PASSWORD: password
     volumes:
+      - pgdata:/var/lib/postgresql/data
       - ./dev/example.sql.xz:/docker-entrypoint-initdb.d/example.sql.xz:ro
 
   redis: