Docker-Compose + Volume + NodeJs - changes not reflected when saved

Question

directory structure

projectroot/
    docker-compose.yml
    frontend/
        Dockerfile
        src/
            node_modules
            package.json
            ....

projectroot/frontend/docker-compose.yml

services:
  frontend:
    build: ./frontend
    ports:
      - 3000:3000
    volumes:
      - ./frontend/src:/app/

Dockerfile

FROM node:12.18.3

COPY /src/package.json .

RUN npm install --save-dev

COPY /src .

EXPOSE 3000

CMD ["npm", "run", "dev"]

The above works. I can run docker-compose up and my app is rendered on localhost:3000 .

However when I make a change on projectroot/frontend/pages/index.js, that change isn't reflected.

I am confused because I copy the contents of /src over to /app in my Dockerfile ( COPY /src . ). If I run the container and bash in, I see /app folder with the contents of my host /src folder.

If I remove the COPY command from Dockerfile , the readout just loops the following:

$ docker-compose up
Recreating pricey_frontend_1 ... done
Attaching to pricey_frontend_1
frontend_1  |
frontend_1  | > src@1.0.0 dev /
frontend_1  | > cross-env NODE_ENV=development nodemon server.js
frontend_1  |
frontend_1  | [nodemon] 2.0.4
frontend_1  | [nodemon] to restart at any time, enter `rs`
frontend_1  | [nodemon] watching path(s): *.*
frontend_1  | [nodemon] watching extensions: js,mjs,json
frontend_1  | [nodemon] starting `npm run dev server.js`
frontend_1  |
frontend_1  | > src@1.0.0 dev /
frontend_1  | > cross-env NODE_ENV=development nodemon server.js "server.js"
*** loops until I kill it***

In my head, removing COPY makes sense because I want to use the host volume src (so that I can update it and the changes reflected on localhost:3000 immediately. What am I missing?

Answer 1

在这里检查这个答案我添加--legacy-watch ，现在它正在响应更改。

ENTRYPOINT [ "nodemon", "--legacy-watch", "--inspect=0.0.0.0", "./src/server.js"]