Btukfyl

I have an express app and I'm trying to setup hot reloading with nodemon using docker for windows 10 as a dev environment. However when I npm install on the volume it doesn't seem to work.

With powershell I use a volume like so:

docker build -t node-api .

docker run --rm -it -p 8080:8080 -v "${PWD}:/usr/src/app" node-api

Which outputs this error:

[nodemon] 1.18.6

[nodemon] to restart at any time, enter `rs`

[nodemon] watching: *.*

[nodemon] starting `node server/server.js`

internal/modules/cjs/loader.js:605

    throw err;

    ^



Error: Cannot find module 'express'

    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:603:15)

    at Function.Module._load (internal/modules/cjs/loader.js:529:25)

    at Module.require (internal/modules/cjs/loader.js:658:17)

    at require (internal/modules/cjs/helpers.js:22:18)

    at Object.<anonymous> (/usr/src/app/server/server.js:1:79)

    at Module._compile (internal/modules/cjs/loader.js:722:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:733:10)

    at Module.load (internal/modules/cjs/loader.js:620:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:560:12)

    at Function.Module._load (internal/modules/cjs/loader.js:552:3)

[nodemon] app crashed - waiting for file changes before starting...

If I exclude the -v flag and docker run then it starts with no errors, but doesn't detect changes or restart on file saves.

Dockerfile

FROM node:alpine



#Create app directory

WORKDIR /usr/src/app



#Install nodemon for hot reloading

RUN npm install nodemon -g



#Install app dependencies

#A wildcard is used to ensure both package.json AND package-lock.json are copied

COPY package*.json ./



RUN npm install



#Bundle app source

COPY . .



EXPOSE 8080

CMD [ "nodemon", "-L", "server/server.js" ]

Folder Structure

server/



    >server.js



Dockerfile



package.json

Github repo for code

The problem is that by mounting the whole host app/ directory as volume, the app/node_modules/ inside the container would be overwritten by the host's app/, thus all dependencies are missing.

The solution is to only mount the source code folder you need, i.e.

docker run --rm -it -p 8080:8080 -v "${PWD}/server:/usr/src/app/server" node-api