Docker and entrypoint

Dockefile

# == Builder ==
FROM golang:1.13.7-alpine3.11 as builder

RUN apk add --no-cache \
        bash=5.0.11-r1 \
        git=2.24.1-r0 \
        mercurial=5.2.1-r0 \
        openssh-client=8.1_p1-r0

ARG SSH_PRIVATE_KEY
RUN mkdir /root/.ssh/
RUN echo "${SSH_PRIVATE_KEY}"  > /root/.ssh/id_rsa
RUN chmod 600 /root/.ssh/id_rsa
RUN git config --global url."git@github.com:mycompany".insteadOf \
    "https://github.com/mycompany"
RUN touch /root/.ssh/known_hosts
RUN ssh-keyscan github.com >> /root/.ssh/known_hosts

WORKDIR /app

# Copy dependencies definition
COPY go.mod .
COPY go.sum .

# Download dependencies
RUN GOPRIVATE=github.com/mycompany go mod download

# Copy remaining source code
COPY . .

# Build binary
RUN CGO_ENABLED=0 go build -a -ldflags "-X main.revision=$(git rev-list -1 HEAD)" -installsuffix cgo -o /app/api-up ./*.go

# == Runner ==
FROM alpine:3.11.3

RUN apk add --no-cache \
        tini=0.18.0-r0

# Copy binary from builder
COPY --from=builder /app/api-up /app/api-up

COPY docker-entrypoint.sh /bin/
ENTRYPOINT ["tini", "--", "docker-entrypoint.sh"]

CMD ["/app/api-up"]

docker-entrypoint

#!/bin/sh

if [ "$1" = '/app/api-up' ]; then
    if [ -n "$PORT" ]; then
        set -- -port="$PORT" "$@"
    else
        set -- -port="8080"
    fi

    if [ -n "$MAX_CONN" ]; then
        set -- "$@" -max-conn="$MAX_CONN"
    fi

    exec /app/api-up "$@"
fi

exec "$@"

Makefile

SSH_PRIVATE_KEY_FILE ?= ~/.ssh/id_rsa
SSH_PRIVATE_KEY ?= `cat $(SSH_PRIVATE_KEY_FILE)`

# Build docker image
.PHONY: docker-image
docker-image:
	@echo Build docker image
	@docker build -t api --build-arg SSH_PRIVATE_KEY="$(SSH_PRIVATE_KEY)" .

run.sh

#!/bin/sh

docker run --rm -it -v $(pwd)/logs:/app/logs \
  -e MAX_CONN=10 \
  -e PORT=9090 \
  logsim