Use npm package wait-on instead of sleep to prevent timing issues

Author: matboehm

Dockerfile

@@ -9,8 +9,8 @@ WORKDIR /home/node/coc-api
 # Copy contents of local folder to `WORKDIR`
 COPY . .
 
-# Install nodemon globally
-RUN npm install --global nodemon db-migrate db-migrate-mysql
+# Install npm packages globally
+RUN npm install --global nodemon db-migrate db-migrate-mysql wait-on
 
 # Install dependencies from package.json
 RUN npm install --quiet --no-warnings

docker-compose.yml

@@ -37,4 +37,4 @@ services:
     depends_on:
       - db
       - mailhog
-    command: bash -c "sleep 5 && db-migrate up && npm run start"
+    command: bash -c "wait-on tcp:db:3306 && db-migrate up && npm run start"