Steps to create
Solution
Create the solution directory
Open solution directory in VsCode
Add readme.md to solution directory.
Add docker-compose.yml to solution directory.
MongoDb Database
Add docker-compose definition:
database:
image: mongo
volumes:
- data:/data/db
environment:
MONGO_INITDB_ROOT_USERNAME: user
MONGO_INITDB_ROOT_PASSWORD: password
Run docker-compose up to test.
Express Backend
Create backend project directory.
Create Dockerfile:
FROM node:lts-alpine
Add docker-compose definition:
backend:
build: ./backend
user: node
tty: true
stdin_open: true
volumes:
- ./backend:/backend
- /backend/node_modules
Create ./backend/.devcontainer.json
{
"dockerComposeFile": "../docker-compose.yml",
"service": "backend",
"workspaceFolder": "/backend"
}
From the WSL terminal open backend in VsCode code ./backend/
Create node project npm init
Install express npm i express
Create server.js add HelloWorld implementation
const express = require('express')
const app = express()
const port = 3000
app.get('/', (req, res) => {
res.send('Hello World!')
})
app.listen(port, () => {
console.log(`Example app listening at http://localhost:${port}`)
})
(Optional) Add npm start script "start": "node server.js"
(Optional) Run npm start verify server can be reached at localhost:3000
Install nodemod npm i --save-dev nodemon
Update npm start script to nodemon "start": "nodemon --inspect=0.0.0.0:9229 server.js"
Restart and verify code changes are picked up.
Create a 'node attach' debug profile.
Add a breakpoint, start debugging, refresh page to hit breakpoint.
Shutdown dev container.
Add publish port and add run command to docker-compose.yml backend service definition.
ports:
- 3000:3000
command: [ "npm", "start"]
Start using docker-compose up and verify server can be reached.
Add npm install process to Dockerfile.
COPY ["package.json", "package-lock.json", "./"]
RUN npm install
COPY . .
Connect backend to MongoDb
Install mongoose npm i mongoose
In backend/server.js, add const mongoose = require('mongoose');
In backend/server.js replace app.listen(port, () => { with
mongoose.connect(
`mongodb://user:password@mongodb:27017/my-temp-db?authSource=admin`,
{
useNewUrlParser: true,
useUnifiedTopology: true,
},
(err) => {
if (err) {
console.error('FAILED TO CONNECT TO MONGODB');
console.error(err);
} else {
console.log('CONNECTED TO MONGODB!!');
app.listen(port);
}
}
);
In docker-compose.yml backend service definition add:
depends_on:
- mongodb
Users and Containers
By default a container is started as root. If the id of the user the container is running user does not match the id of the user in the host system, then files created in the container mapped by a bind mount to the host will not be editable in the host.
node images come with a non-root user named 'node' id=1000. If this id matches the id of the user on the host system then this user account can be selected in docker-compose.yml and files will be able to be read/written on both sides of any bind mount.
dotnet images do not come with a default non-root user. One can be created by adding the following directive to the Dockerfile, where the '1000' should match the id of the user on the host system.
RUN useradd -ms /bin/bash -u 1000 dotnet`
Useful commands
Display current user whoami
Display current user id id <name>
Display list of all users on system cat /etc/passwd