Runtime error in docker container, Module not found-CodePudding

I am sorry for the newbie question, but I have been figuring out this error, I have an Express app and I am trying to run it as a docker container. I've used this Dockerfile:

FROM node:14.17.0-alpine
COPY /src /nodejs
WORKDIR /nodejs
ADD package*.json ./
RUN npm install

CMD [ "node", "app.js" ]

and this is my package.js file :

{
  "name": "server",
  "version": "1.0.0",
  "description": "",
  "main": "app.js",
  "scripts": {
    "start": "node app.js",
    "dev": "nodemon app.js -e js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "express": "^4.17.1",
    "express-rate-limit": "^5.1.3",
    "nodemon": "^2.0.3",
    "prom-client": "^12.0.0",
    "puppeteer": "^10.4.0"
  }
}

I'm using windows 10 and the command I used to deploy the container is :

docker run --name express-api -d -p 4000:4000 docker-express-app

the error that I get after executing the above command, in power shell:

internal/modules/cjs/loader.js:888

  throw err;

  ^


Error: Cannot find module '/nodejs/app.js'

    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:885:15)

    at Function.Module._load (internal/modules/cjs/loader.js:730:27)

    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:72:12)

    at internal/main/run_main_module.js:17:47 {

  code: 'MODULE_NOT_FOUND',

  requireStack: []

}

any idea on this issue is appreciated.

P.S: my project hierarchy is like so :

https://i.stack.imgur.com/ptlkI.png

CodePudding user response：

You didn't COPY the app.js file in your container.

WORKDIR /nodejs
COPY src .
COPY app.js .
ADD package*.json ./
RUN npm install

CMD [ "node", "app.js" ]

This should fix it.

I think a more easier way could be to make a dockerignore file and copy everything. Another problem is that you're using ADD instead of COPY. You just need to copy your files in the container and I think COPY would suffice as ADD has some extra functionality which can be confusing.