add: deploy instructions to readme

README.md

@@ -1,3 +1,34 @@
 # photovoter_deploy
 
-Docker photovoter deploy scripts
+Docker photovoter deploy scripts
+
+## Build
+### Python + ImageMagick base container
+```
+docker build --tag pythonmagick - < Dockerfile.pythonmagick
+```
+
+### Photovoter + dependencies + random credentials
+```
+docker build --tag photovoter-backend \
+--build-arg=USERNAME=(tr --delete --complement "[:alnum:]" </dev/random | head --bytes=5) \
+--build-arg=USERPASS=(tr --delete --complement "[:alnum:]" </dev/random | head --bytes=56) \
+- < Dockerfile.photovoter-backend
+```
+
+## Run
+```
+mkdir --parents photovoter_data/{original,image}
+docker-compose --file docker-compose.yml up
+```
+
+## Get current credentials
+### From active deployment
+```
+docker exec photovoter_backend_1 grep 'CRED_' /opt/photovoter_backend/config.py
+```
+
+### From inactive deployment
+```
+docker run --rm photovoter-backend:latest grep 'CRED_' /opt/photovoter_backend/config.py
+```