Dockerfile-builder

# 1.23.1-alpine3.20
FROM golang@sha256:ac67716dd016429be8d4c2c53a248d7bcdf06d34127d3dc451bda6aa5a87bc06 as builder

RUN ln -s /usr/local/go/bin/go /usr/local/bin/go

RUN apk add --no-cache curl wget gcc make bash git musl-dev libc6-compat gettext

WORKDIR /go/github.com/thought-machine/prometheus-cardinality-exporter

COPY . .

RUN go build ./...

RUN go test ./... -race

# So the binary is where we expect it
# env var and flags ensure a static binary
RUN CGO_ENABLED=0 go build -ldflags="-extldflags=-static" .

# alpine:3.20.3
FROM alpine@sha256:beefdbd8a1da6d2915566fde36db9db0b524eb737fc57cd1367effd16dc0d06d

EXPOSE 9090

COPY --from=builder /go/github.com/thought-machine/prometheus-cardinality-exporter/prometheus-cardinality-exporter /home/app/prometheus-cardinality-exporter

# Max user
RUN addgroup -g 255999 -S app && \
    adduser -u 255999 -S app -G app

RUN chmod +x /home/app/prometheus-cardinality-exporter

USER app

ENTRYPOINT ["/home/app/prometheus-cardinality-exporter"]