Basecamp for Go apps

README.md

Codebase for Go applications with docker based work flow

Born out of the need to deploy function to a heterogeneous serverless cluster via raspberry pi and other commondity off the shelf hardware.

This Repo helps one get started to build and deploy applications, serverless functions, and/or restful apis. If one can write it in go then exeute it securely via docker. The end docker image is based on scratch and would contain a multi-arch image with just the application that has full multi arch and multi os support is baked in.

Dependancies

• docker
• docker hub account
• good ide (e.g. vim/emacs)
• gnu make
• knowledge of Go

Usage

Drop these three files into your project folder and use make to build/test/exec go commands

make all - Builds linux arm and amd64 versions of application and bundles a multi arch docker image make EXEC=... gocmd - pass values to go via EXEC='...' to run go command (e.g. make EXEC="run main.go" gocmd) make docs - Runs godoc on port 6060, open/xdg-open/start/pipe http://localhost:6060 to read make test - Run unit tests with code coverage output make release - Builds all images defined with IMAGES='...' then pushes to docker hub (defaults to linux-armv7 and linux-amd64)

Roadmap

• Support label-schema.org/rc1
• Support matrix.dapla.net/schema
• Add matrix.dapla.net/stack.yml
• bundle for python cookiecutter (or nodejs/go equivalents)

Dockerfile

FROM golang:1.13-alpine as base
ARG GOOS=linux
ARG GOARCH=amd64
ARG GOARM
ENV GOARCH=$GOARCH
ENV GOOS=$GOOS
ENV GOARM=$GOARM
ENV CGO_ENABLED=0
WORKDIR /app
COPY . /app
RUN  apk add --update --no-cache ca-certificates git tzdata && \
     adduser -S -D -H svcrunner && \
     go get -d -v . && \
     go mod download && \
     go mod verify

FROM base as test
RUN go test -coverage ./...

FROM base as builder
RUN go build -a -ldflags='-w -s' -o build/service .

FROM scratch
ENV TZ=Etc/UTC
ENV LANG=en_US.utf8
ENV LC_LANG=en_US.utf8
ENV LC_ALL=en_US.utf8
COPY --from=base /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs
COPY --from=base /etc/passwd /etc/group /etc/shadow /etc/
COPY --from=base /usr/share/zoneinfo /usr/share/zoneinfo
COPY --from=builder /app/build/service /service
USER svcrunner
ENTRYPOINT ["/service"]
EXPOSE 8080

Dockerfile.doc

FROM golang:1.13-alpine 
WORKDIR /app
COPY . /app
EXPOSE 6060
RUN go install golang.org/x/tools/cmd/godoc
CMD go exec godoc -http=:6060

Makefile

IMAGE		:= $(shell basename "$(shell pwd)")
OS		:= linux
ARCH		:= amd64
IMAGES		:= linux-arm7 linux-amd64 

DOCKER		:= $(shell basename "$(shell which winpty 2>/dev/null)")
DOCKER		+= docker

.PHONY : all $(IMAGES) release docs build gocmd

all: release

clean:
  @-docker image ls --format '{{.Repository}} {{.ID}}' | awk '/$(IMAGE)/ { system("docker image rm "$$2') }'

release: $(IMAGES)
  @-$(DOCKER) manifest push $(IMAGE):latest

build:
	@$(DOCKER) image build $(BUILD_OPTS)  -t $(TAG) .

gocmd:
	@$(DOCKER) run --rm -ti \
		-v /$(shell pwd)://app \
		--workdir=//app \
		--entrypoint=go \
		-e CGO_ENABLED=0 \
		golang:1.13-alpine $(EXEC)

test: EXEC := test -cover ./...
test: gocmd

docs: TAG := "$(IMAGE):docs"
docs: Dockerfile.doc  build
  @$(DOCKER) run --rm -ti -p 6060:6060/tcp $(IMAGE):docs

$(IMAGE): BUILD_OPTS := --build-arg GOARCH=$(ARCH)
$(IMAGE): BUILD_OTPS += --build-arg GOOS=$(OS)
$(IMAGE): BUILD_OPTS += --build-arg GOARM=$(ARM)
$(IMAGE): TAG := $(IMAGE):$(OS)-$(ARCH)$(ARM)
$(IMAGE): Dockerfile build

arm:
  @$(DOCKER) manifest create -a $(IMAGE):latest $(TAGE) --os $(OS) --arch $(ARCH) --variant $(ARM)
  
intel:
  @$(DOCKER) manifest create -a $(IMAGE):latest $(TAGE) --os $(OS) --arch $(ARCH)

linux-arm64: OS=linux
linux-arm64: ARCH=arm64
linux-arm64: $(IMAGE) arm

linux-arm7: OS=linux
linux-arm7: ARCH=arm
linux-arm7: ARM=7
linux-arm7: $(IMAGE) arm

linux-arm6: OS=linux
linux-arm6: ARCH=arm
linux-arm6: ARM=6
linux-arm6: $(IMAGE) arm

linux-arm5: OS=linux
linux-arm5: ARCH=arm
linux-arm5: ARM=5
linux-arm5: $(IMAGE) arm

linux-amd64: OS=linux
linux-amd64: ARCH=amd64
linux-amd64: $(IMAGE) intel

windows-amd64: OS=windows
windows-amd64: ARCH=amd64
windows-amd64: $(IMAGE) intel