update README

README.md

@@ -1,24 +1,28 @@
-# README
-
-This README would normally document whatever steps are necessary to get the
-application up and running.
-
-Things you may want to cover:
-
-* Ruby version
-
-* System dependencies
-
-* Configuration
-
-* Database creation
-
-* Database initialization
-
-* How to run the test suite
-
-* Services (job queues, cache servers, search engines, etc.)
-
-* Deployment instructions
-
-* ...
+Just pull this image, link with Postgres container, create db and migrate in running container and that's it.
+
+Or let Docker Compose to make this job done (https://github.com/apiqcms/kms_docker/blob/master/docker-compose.yml):
+
+```
+version: '3'
+services:
+  db:
+    image: postgres
+  web:
+    image: webgradus/kms
+    command: bundle exec rails s -p 3000 -b '0.0.0.0'
+    environment:
+      SECRET_TOKEN: abc
+      RAILS_SERVE_STATIC_FILES: 'true'
+    volumes:
+      - .:/kms
+    ports:
+      - "3000:3000"
+    depends_on:
+      - db
+```
+
+Environment variables you should care about are:
+* `SECRET_TOKEN` - for secrets.yml
+* `RAILS_SERVE_STATIC_FILES` - for serving static files by Rails
+* `DATABASE` - database name prefix. Entire name is ENV['DATABASE'] + '_production'
+* `POSTGRES_PASSWORD` - which is used for "Postgres" image