Authenticate to private npm registry from Dockerfile in azure?

Question

I have the below Dockerfile:

FROM node:alpine

WORKDIR ./usr/local/lib/node_modules/npm/

COPY .npmrc ./

COPY package.json ./
COPY package-lock.json ./
RUN npm ci

COPY . .


EXPOSE 3000

CMD ["npm", "run", "start-prod"]

This file is used in an azure pipeline like so:

variables:
  - name: NPMRC_LOCATION
    value: $(Agent.TempDirectory)
    
  - stage: BuildPublishDockerImage
    displayName: Build and publish Docker image
    dependsOn: Build
    jobs:
      - job: BuildPublishDockerImage
        steps:
          - checkout: self
          - task: DownloadSecureFile@1
            name: npmrc
            inputs:
              secureFile: .npmrc
          - task: npmAuthenticate@0
            inputs:
              workingFile: $(NPMRC_LOCATION)/.npmrc
          - task: Docker@2
            displayName: Build a Docker image
            inputs:
              command: build
              arguments: --no-cache

I know .npmrc should be in that location (I run RUN ls in the Dockerfile and its there).
However when I run it I keep getting this error:

failed to solve with frontend dockerfile.v0: failed to build LLB: failed to compute cache key: "/.npmrc" not found: not found

I just want to authenticate to a private npm registry. I'm mystified by this. Grateful for any help.

Answer 1

You can in Dockerfile set registry

npm config set registry