chore: make Docker environment easier to work with (#24)

- Substitutes admin token directly in `.env`
- Sets ownership of `docker/synapse` to the user executing `docker`
(this requires the directory to be present and owned by the user,
otherwise docker will create it for us and set ownership to root)

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Justfile

@@ -29,6 +29,7 @@ nuke_db:
 # Generates the synapse configuration file and saves it
 gen_synapse_conf: dotenv
   docker run -i --rm \
+    -u $(id -u):$(id -g) \
     -v ./docker/synapse:/data \
     --env-file .env \
     matrixdotorg/synapse:v1.96.1 generate
@@ -37,15 +38,18 @@ gen_synapse_conf: dotenv
 gen_synapse_admin: dotenv
   docker compose exec -i synapse \
     register_new_matrix_user http://localhost:8008 \
+    -u $(id -u):$(id -g) \
     -c /data/homeserver.yaml \
     -u admin \
     -p admin \
     -a
 
 # Retrieves admin access token uses de-facto admin user and Development Database Credentials
 get_access_token:
-  curl -sS -d '{"type":"m.login.password", "user":"admin", "password":"admin"}' \
-  http://localhost:8008/_matrix/client/v3/login | jq --raw-output '.access_token' > access_token.txt
+  sed -i "s/COMMUNE_SYNAPSE_ADMIN_TOKEN='.*'/COMMUNE_SYNAPSE_ADMIN_TOKEN='$( \
+    curl -sS -d '{"type":"m.login.password", "user":"admin", "password":"admin"}' \
+    http://localhost:8008/_matrix/client/v3/login | jq --raw-output '.access_token' \
+  )'/" .env
 
 # Runs backend dependency services
 backend: dotenv

docker-compose.yml

@@ -14,7 +14,7 @@ services:
       - '8001:8001'
     volumes:
       - redis-state:/data
-  
+
   synapse_database:
     image: 'postgres:16'
     ports:
@@ -27,6 +27,7 @@ services:
 
   synapse:
     image: 'ghcr.io/element-hq/synapse:v1.100.0'
+    user: '${UID:-1000}:${GID:-1000}'
     ports:
       - '8008:8008'
       - '8448:8448'