fix: allow postgres&redis locaion customization

Resources/docker/app/README.md

@@ -0,0 +1,35 @@
+# Quick reference
+
+- **Maintained by**:  
+    [the PokeAPI Contributors](https://github.com/PokeAPI/pokeapi/graphs/contributors)
+
+- **Where to get help**:  
+    [PokeAPI Slack](http://pokeapi.slack.com/).
+
+- **Where to file issues**:  
+    [https://github.com/PokeAPI/pokeapi/issues](https://github.com/PokeAPI/pokeapi/issues)
+
+- **Source of this description**:  
+    [pokeapi repo's `Resources/docker/app/` directory](https://github.com/PokeAPI/pokeapi/blob/master/Resources/docker/app/README.md)
+
+## Supported tags and respective `Dockerfile` links
+
+- [`latest`](https://github.com/PokeAPI/pokeapi/blob/master/Resources/docker/app/Dockerfile)
+
+## What is PokeAPI?
+
+PokeAPI is a full RESTful API linked to an extensive database detailing everything about the Pokémon main game series.
+
+> [pokeapi.co](https://pokeapi.co/)
+
+![logo](https://raw.githubusercontent.com/PokeAPI/media/master/logo/pokeapi_256.png)
+
+## How to use this image
+
+This container connects to a Postgres database via the environment variables `POSTGRES_DB`, `POSTGRES_USER`, `POSTGRES_PASSWORD`, `POSTGRES_HOST`, `POSTGRES_PORT`.
+
+The container connects to a Redis cache via the environment variable `REDIS_CONNECTION_STRING`.
+
+### Run the container using Compose
+
+The container exposes port `80`. It's recommended to use the provided [docker-compose.yml](https://github.com/PokeAPI/pokeapi/blob/master/docker-compose.yml) to start a container from this image.

config/docker-compose.py

@@ -8,16 +8,15 @@ DATABASES = {
         "NAME": os.environ.get("POSTGRES_DB", "pokeapi"),
         "USER": os.environ.get("POSTGRES_USER", "ash"),
         "PASSWORD": os.environ.get("POSTGRES_PASSWORD", "pokemon"),
-        "HOST": "db",
-        "PORT": 5432,
+        "HOST": os.environ.get("POSTGRES_HOST", "db"),
+        "PORT": os.environ.get("POSTGRES_PORT", 5432)
     }
 }
 
-
 CACHES = {
     "default": {
         "BACKEND": "django_redis.cache.RedisCache",
-        "LOCATION": "redis://cache:6379/1",
+        "LOCATION": os.environ.get("REDIS_CONNECTION_STRING", "redis://cache:6379/1") ,
         "OPTIONS": {
             "CLIENT_CLASS": "django_redis.client.DefaultClient",
         },