Dockerfile

# DO NOT USE THIS IN PRODUCTION
# 
# This Dockerfile builds a Docker image for a pre-configured Backstage instance
# with the Stack Overflow Internal plugins installed. It’s designed as a quick way to try 
# out the integration without having to set it up yourself. 
#
# This is not intended for production use.

# Stage 1 - Create yarn install skeleton layer
FROM --platform=$BUILDPLATFORM node:22-bookworm-slim AS packages

WORKDIR /app
COPY backstage.json package.json yarn.lock ./
COPY .yarn ./.yarn
COPY .yarnrc.yml ./

COPY packages packages

# Comment this out if you don't have any internal plugins
COPY plugins plugins

RUN find packages \! -name "package.json" -mindepth 2 -maxdepth 2 -exec rm -rf {} \+

# Stage 2 - Install dependencies and build packages
FROM node:22-bookworm-slim AS build

# Set Python interpreter for `node-gyp` to use
ENV PYTHON=/usr/bin/python3

# Install isolate-vm dependencies, these are needed by the @backstage/plugin-scaffolder-backend.
RUN --mount=type=cache,target=/var/cache/apt,sharing=locked \
    --mount=type=cache,target=/var/lib/apt,sharing=locked \
    apt-get update && \
    apt-get install -y --no-install-recommends python3 g++ build-essential git && \
    rm -rf /var/lib/apt/lists/*

# Install sqlite3 dependencies. You can skip this if you don't use sqlite3 in the image,
# in which case you should also move better-sqlite3 to "devDependencies" in package.json.
RUN --mount=type=cache,target=/var/cache/apt,sharing=locked \
    --mount=type=cache,target=/var/lib/apt,sharing=locked \
    apt-get update && \
    apt-get install -y --no-install-recommends libsqlite3-dev && \
    rm -rf /var/lib/apt/lists/*

USER node
WORKDIR /app

COPY --from=packages --chown=node:node /app .

# Install with increased timeout and without cache mount to avoid cross-platform issues
RUN yarn install --immutable --network-timeout 300000

COPY --chown=node:node . .

RUN yarn tsc
RUN yarn --cwd packages/backend build

RUN mkdir packages/backend/dist/skeleton packages/backend/dist/bundle \
    && tar xzf packages/backend/dist/skeleton.tar.gz -C packages/backend/dist/skeleton \
    && tar xzf packages/backend/dist/bundle.tar.gz -C packages/backend/dist/bundle

# Stage 3 - Build the actual backend image and install production dependencies
FROM node:22-bookworm-slim

# Set Python interpreter for `node-gyp` to use
ENV PYTHON=/usr/bin/python3

# Install isolate-vm dependencies, these are needed by the @backstage/plugin-scaffolder-backend.
RUN --mount=type=cache,target=/var/cache/apt,sharing=locked \
    --mount=type=cache,target=/var/lib/apt,sharing=locked \
    apt-get update && \
    apt-get install -y --no-install-recommends python3 g++ build-essential && \
    rm -rf /var/lib/apt/lists/*

# Install sqlite3 dependencies. You can skip this if you don't use sqlite3 in the image,
# in which case you should also move better-sqlite3 to "devDependencies" in package.json.
RUN --mount=type=cache,target=/var/cache/apt,sharing=locked \
    --mount=type=cache,target=/var/lib/apt,sharing=locked \
    apt-get update && \
    apt-get install -y --no-install-recommends libsqlite3-dev && \
    rm -rf /var/lib/apt/lists/*

# From here on we use the least-privileged `node` user to run the backend.
USER node

# This should create the app dir as `node`.
# If it is instead created as `root` then the `tar` command below will
# fail: `can't create directory 'packages/': Permission denied`.
# If this occurs, then ensure BuildKit is enabled (`DOCKER_BUILDKIT=1`)
# so the app dir is correctly created as `node`.
WORKDIR /app

# Copy the install dependencies from the build stage and context
COPY --from=build --chown=node:node /app/.yarn ./.yarn
COPY --from=build --chown=node:node /app/.yarnrc.yml  ./
COPY --from=build --chown=node:node /app/backstage.json ./
COPY --from=build --chown=node:node /app/yarn.lock /app/package.json /app/packages/backend/dist/skeleton/ ./

# Note: The skeleton bundle only includes package.json files -- if your app has
# plugins that define a `bin` export, the bin files need to be copied as well to
# be linked in node_modules/.bin during yarn install.
RUN yarn workspaces focus --all --production && rm -rf "$(yarn cache clean)"

# Copy the built packages from the build stage
COPY --from=build --chown=node:node /app/packages/backend/dist/bundle/ ./

# Copy any other files that we need at runtime
COPY --chown=node:node app-config*.yaml ./

# This will include the examples, if you don't need these simply remove this line
COPY --chown=node:node examples ./examples

# This switches many Node.js dependencies to production mode.
ENV NODE_ENV=development

# This disables node snapshot for Node 20 to work with the Scaffolder
ENV NODE_OPTIONS="--no-node-snapshot"

CMD ["node", "packages/backend", "--config", "app-config.docker-local.yaml"]