Installing a local npm package in Dockerfile - node.js

Question

I have a local package that I packed into an npm package using npm pack.
I then install this package to some nodejs apps that are external to this local package using npm install path/to/package.tgz. This works like a charm, but now I want to dockerize the apps and I can't manage to install the local package.
My structure looks like this:
-my_package
|-package.tgz
-app1
|-app1.js
|-Dockerfile
-app2
|-app2.js
|-Dockerfile
My Dockerfile looks like this:
FROM node:16
WORKDIR /app
# Copy and download dependencies
COPY package.json .
RUN npm install
# Copy the source files into the image
COPY . .
EXPOSE 4002
CMD ["npm", "start"]
And the error I'm getting when running docker build . -t js/app1 is:
npm WARN tarball tarball data for #my_package#file:/package.tgz (sha512-u9tY/j1VOzO1y1RpcCgYteDOEsh7TaSMYwmR2Rs7hoJopE11qa1XcnrrMKNx1/H/aHsZ3Gr0bOMx1SygYTf/rg==) seems to be corrupted. Trying again.
npm WARN tarball tarball data for #my_package#file:/package.tgz (sha512-u9tY/j1VOzO1y1RpcCgYteDOEsh7TaSMYwmR2Rs7hoJopE11qa1XcnrrMKNx1/H/aHsZ3Gr0bOMx1SygYTf/rg==) seems to be corrupted. Trying again.
npm notice
npm notice New major version of npm available! 8.19.2 -> 9.2.0
npm notice Changelog: <https://github.com/npm/cli/releases/tag/v9.2.0>
npm notice Run `npm install -g npm#9.2.0` to update!
npm notice
npm ERR! code ENOENT
npm ERR! syscall open
npm ERR! path /my_package/package.tgz
npm ERR! errno -2
npm ERR! enoent ENOENT: no such file or directory, open '/my_package/package.tgz'
npm ERR! enoent This is related to npm not being able to find a file.
npm ERR! enoent
npm ERR! A complete log of this run can be found in:
npm ERR! /root/.npm/_logs/2022-12-09T04_54_04_868Z-debug-0.log
The command '/bin/sh -c npm ci' returned a non-zero code: 254
Some times I get null instead of the sha512 stuff, otherwise the error is the same.
Is there anything I can do to fix this?
Thanks!

Answer 1

The documentation says:
COPY obeys the following rules:
The path must be inside the context of the build; you cannot
COPY ../something /something, because the first step of a docker build
is to send the context directory (and subdirectories) to the docker
daemon.
The easiest fix is to paste the file(s) you need into the same folder that your Dockerfile is in.