Updated README.md at /react-express-mongodb /backend/

react-express-mongodb/backend/README.md

@@ -4,18 +4,18 @@ You will find this `DockerFile` file in the root directory of the project.
 
 ```bash
 FROM node:13.13.0-stretch-slim
-#Argument that is passed from docer-compose.yaml file
+#Argument that is passed from docker-compose.yaml file
 ARG NODE_PORT
 #Echo the argument to check passed argument loaded here correctly
 RUN echo "Argument port is : $NODE_PORT"
 # Create app directory
 WORKDIR /usr/src/app
-#COPY . .
-COPY . .
+# Copy dependency definitions
+COPY package.json /usr/src/app
 # Install app dependencies
-# A wildcard is used to ensure both package.json AND package-lock.json are copied
-# where available (npm@5+)
 RUN npm install
+# Get all the code needed to run the app
+COPY . /usr/src/app
 #In my case my app binds to port NODE_PORT so you'll use the EXPOSE instruction to have it mapped by the docker daemon:
 EXPOSE ${NODE_PORT}
 CMD npm run dev
@@ -29,13 +29,15 @@ CMD npm run dev
 
 - On third line we log to check argument is successfully read 
 
-- On fourth line we sets a working directory from where the app code will live inside the Docker container.
+- On fourth line we set a working directory ,where the app code will be set to present inside the Docker container.
 
-- On fifth line, we are copying/bundling our code working directory into container working directory on line three.
+- On fifth line, we are copying our dependency file (i,e package.json) into container working directory which was set on line four.
 
-- On line seven, we run npm install for dependencies in container on line four.
+- On sixth line, we run npm install for dependencies installation in container.
+
+- On line seven,  we are copying/bundling our code working directory into container working directory which was set on line four.
 
 - On Line eight, we setup the port, that Docker will expose when the container is running. In our case it is the port which we define inside `.env` file, read it from `docker-compose` then passed as a argument to the (backend)`DockerFile`.
 
-- And in last, we tell docker to execute our app inside the container by using node to run `npm run dev. It is the command which I registered in __package.json__ in script section.
+- And at last, we tell docker to execute our app inside the container by using node to run `npm run dev. It is the command which I registered in __package.json__ in script section.
 ###### :clipboard: `Note: For development purpose I used __nodemon__ , If you need to deploy at production you should change CMD from __npm run dev__ to __npm start__.`