Dockerfile.coverage

# Coverage overlay image for parse-server-mongo.
#
# Extends the base sample image build chain (node:20-bookworm-slim +
# parse-server deps + index.js) with c8 (for `c8 report`) and a
# tiny JavaScript entrypoint shim that registers SIGTERM/SIGINT
# handlers calling process.exit(0) — without that, parse-server's
# express server pins the event loop and signal-driven kills
# bypass V8's coverage flush, leaving NODE_V8_COVERAGE empty.
#
# IMPORTANT: this image is only consumed by docker-compose.coverage.yml.
# The base Dockerfile and docker-compose.yml stay uninstrumented so
# enterprise's keploy compat lane pays no coverage-instrumentation
# cost.
FROM node:20-bookworm-slim

RUN apt-get update && \
    apt-get install -y --no-install-recommends ca-certificates curl dumb-init && \
    rm -rf /var/lib/apt/lists/*

WORKDIR /usr/src/app

COPY package*.json ./
RUN npm install --omit=dev

COPY index.js ./

# c8 is the report generator (we use NODE_V8_COVERAGE for raw data
# collection at runtime, then `c8 report` post-hoc to produce
# json-summary / lcov). Installing globally keeps the app's own
# node_modules byte-identical to the base image.
RUN npm install -g c8@10.1.2

# Graceful-shutdown shim: parse-server's app.listen() pins the
# event loop, so a `compose stop` (SIGTERM) would kill node by
# signal — exit code 143 — before V8's NODE_V8_COVERAGE writer
# runs. Calling process.exit(0) from a SIGTERM handler turns the
# kill into a clean exit, so V8 dumps coverage to NODE_V8_COVERAGE
# before the process terminates.
RUN printf "process.on('SIGTERM', () => process.exit(0));\nprocess.on('SIGINT', () => process.exit(0));\nrequire('/usr/src/app/index.js');\n" \
    > /usr/src/app/coverage-entrypoint.js

EXPOSE 1337

ENTRYPOINT ["dumb-init", "--"]
CMD ["node", "/usr/src/app/coverage-entrypoint.js"]