Added db:migrate and DATABASE variable

Dockerfile

@@ -27,9 +27,8 @@ RUN gem install bundler && bundle install
 
 VOLUME /app/db/database
 
-RUN bin/rake assets:precompile
+RUN bundle exec rake assets:precompile
 
 EXPOSE 3000
 
-ENTRYPOINT ["bundle", "exec"]
-CMD ["rails", "server", "-b", "0.0.0.0"]
+CMD cd /app && rake 'db:migrate' && bundle exec rails server -b 0.0.0.0

README.md

@@ -25,10 +25,6 @@ docker run -d --name snibox \
               snibox
 ```
 
-After first run you probably will see error due to database hasn't been initialized in the attached volume. Pleas run following command to create empty database:
+Default database file location is `/app/db/database/snibox.sqlite3`, however you can redefine it by using environment variable `DATABASE`.
 
-```bash
-docker exec <container_id> /app/bin/rails db:migrate
-```
-
-This will create new database instance and Snibox is ready to go.
+Container is running `rake db:migrate` on every start, in order to either create database if not exist, or update database scheme if required, so backups are highly recommended.

config/database.yml

@@ -2,4 +2,4 @@ development:
   adapter: sqlite3
   pool: 5
   timeout: 5000
-  database: db/database/snibox.sqlite3
+  database: <%= ENV['DATABASE'] || "db/database/snibox.sqlite3" %>