How to run multiple applications with single mongodb using docker

问题

I want to be able to run two separate apps in two containers - one for each independent app. Then both apps should be able to communicate with the 3rd container which will hold MongoDB.

1. Folder structure on my local machine

   /Users/me/Dev: Dockerfile, docker-compose.yml 
   /Users/me/Dev/App1: with source code and package.json for app1
   /Users/me/Dev/App2: with source code and package.json for app2
   /Users/me/Dev/data/db: I wanna keep datafile for Mongo
   

2. dockerfile - but honestly it does not look right too me to repeat twice for both apps. (Its a first time I am using docker so am not yet familiar with how to best prepare the Dockerfile for my scenario)

   FROM node:8.9.1
   WORKDIR ./app1/
   COPY ./package.json ./app1/
   RUN npm install
   CMD npm start
   COPY ./app1/ ./app1/
   EXPOSE 8081
   #
   FROM node:8.9.1
   WORKDIR ./app2/
   COPY ./package.json ./app2/
   RUN npm install
   CMD npm start
   COPY ./app2/ ./app2/
   EXPOSE 8082
   

3. docker-compose.yml

   version: '2'
   
   services:
   app1:
   build: .
   volumes:
     - .:/app1
   ports:
     - "8082:8082"
   links:
     - mongo
   depends_on:
     - mongo
   
   # app2:
   #   build: .
   #   volumes:
   #     - .:./app2
   #   ports:
   #     - "8081:8081"
   #   links:
   #     - mongo
   #   depends_on:
   #     - mongo
   
   mongo:
   image: mongo:3.4.10
   volumes:
       - './dev/data/db:/data/db'
   ports:
       - "27017:27017"
   

Few issues: On docker-compose build for example I got - ERROR: Service 'app1' failed to build: COPY failed: stat /var/lib/docker/tmp/docker-builder287108072/package.json: no such file or directory

Even if I tried multiple ways of providing the path in Dockerfile and d-compose I still am not convinced this is gonna work.

So I need some guidance on how to prepare Dockerfile and docker compose in my main DEV folder (as described above) so that docker will start up 3 containers (app1, app2, mongo) all on the same docker network to communicate with each other.

回答1:

Approach#1 Just correct your Dockerfile

Path need to be replaced with the folder path first

correct it with

COPY ./App1/package.json ./app1/

COPY ./App2/package.json ./app2/

But this look wrong practice. Folow bellow steps to create the docker images and deploy them with the docker-compose.yml just like mongo image you have to create your own image and run them with compose.

Approach#2 Good practice to deploy apps

App1 Docker Image

1. Goto your App1 folder and create a Dockerfile

   Dockerfile

   FROM node:8.9.1
   WORKDIR ./app1/
   COPY ./package.json ./app1/
   RUN npm install
   CMD npm start
   COPY ./app1/ ./app1/
   EXPOSE 8081
   

2. Create docker images with

   docker build -t app1Image .

App2 Docker Image

1. Goto your App2 folder and create a Dockerfile

   Dockerfile

   FROM node:8.9.1
   WORKDIR ./app2/
   COPY ./package.json ./app2/
   RUN npm install
   CMD npm start
   COPY ./app2/ ./app2/
   EXPOSE 8081
   

2. Create docker images with

   docker build -t app1Image .

Deploy Image with compose

1. Create docker-compose.yml in Dev folder

   docker-compose.yml

   version: '2'
   services:
      app1:
        image: app1Image
        ports:
          - 8082:8082
        links:
          - mongo
        depends_on:
          - mongo
      app2:
        image: app2Image
        ports:
          - 8081:8081
        links:
          - mongo
        depends_on:
          - mongo
      mongo:
        image: mongo:3.4.10
        ports:
          - 27017:27017
        volumes:
          - './dev/data/db:/data/db'
        links:
          - mongo
        depends_on:
          - mongo
   

2. RUN App with docker-compose

   docker-compose up -d

来源：https://stackoverflow.com/questions/48841261/how-to-run-multiple-applications-with-single-mongodb-using-docker