[SOLVED] Docker Compose couldn't find a package.json file in "/app"

Docker Compose couldn't find a package.json file in "/app"

Here is my project struture

.
├── README.md
├── docker-compose.yml
└── frontend
    ├── Dockerfile
    ├── README.md
    ├── build
    ├── package.json
    ├── yarn.lock
    └── ...

Docker-compose.yml

version: '3.7'

services:
  frontend:
    build:
      context: frontend
      dockerfile: Dockerfile
    volumes:
      - '.:/app'
      - '/app/node_modules'
    ports:
      - 3000:3000

Dockerfile

FROM node:14-alpine

WORKDIR /app

COPY ./package.json /app/package.json
RUN yarn install --no-lockfile

COPY . .

CMD ["yarn", "start"]

If i build container using docker, it works fine

But docker-compose up --build always returns

Attaching to book-marketplace_frontend_1
frontend_1  | yarn run v1.22.15
frontend_1  | error Couldn't find a package.json file in "/app"
frontend_1  | info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
book-marketplace_frontend_1 exited with code 1

it's weird that docker-compose can still run yarn install ( which needs package.json) but can not locate it later. Hope someone can help me

Solution

Because you are already in workdir app as you earlier defined as WORKDIR. So change the line to:

COPY ./package.json /package.json