Reworked Dockerfile for a more production oriented usage

- Added .dockerignore to speed up build context and avoid rebuilding when unecessary
- Specified Alpine and Go versions as build arguments
- Specified Go target CPU architecture as build arguments to be able to build for ARM devices
- Specified base images as build arguments to be able to build for ARM devices
- Trimmed down size of final image using `-a -installsuffix cgo -ldflags="-s -w"` go build flags and by copying the statically built binary only to the final image
- Added clear build and run instructions for the Docker container

.dockerignore

@@ -0,0 +1,11 @@
+.circleci
+.github
+docs
+test
+.gitignore
+.goreleaser.yml
+*.md
+coverage.txt
+Dockerfile
+LICENSE
+test.sh

Dockerfile

@@ -1,15 +1,16 @@
-# run with:
+ARG BASE_IMAGE_BUILDER=golang
-# docker build -t lazydocker .
+ARG BASE_IMAGE=alpine
-# docker run -it lazydocker:latest /bin/sh -l
+ARG ALPINE_VERSION=3.10
+ARG GO_VERSION=1.12.6
 
-FROM golang:alpine
+FROM ${BASE_IMAGE_BUILDER}:${GO_VERSION}-alpine${ALPINE_VERSION} AS builder
+ARG GOARCH=amd64
+ARG GOARM
 WORKDIR /go/src/github.com/jesseduffield/lazydocker/
 COPY ./ .
-RUN CGO_ENABLED=0 GOOS=linux go build
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=${GOARCH} GOARM=${GOARM} go build -a -installsuffix cgo -ldflags="-s -w"
 
-FROM alpine:latest
+FROM ${BASE_IMAGE}:${ALPINE_VERSION}
-RUN apk add -U git xdg-utils
+RUN apk --update add -q --progress --no-cache -U git xdg-utils
-WORKDIR /go/src/github.com/jesseduffield/lazydocker/
+ENTRYPOINT [ "lazydocker" ]
-COPY --from=0 /go/src/github.com/jesseduffield/lazydocker /go/src/github.com/jesseduffield/lazydocker
+COPY --from=builder /go/src/github.com/jesseduffield/lazydocker/lazydocker /usr/bin/lazydocker
-COPY --from=0 /go/src/github.com/jesseduffield/lazydocker/lazydocker /bin/
-RUN echo "alias gg=lazydocker" >> ~/.profile

README.md

@@ -48,6 +48,55 @@ required go version: 1.12
 go get github.com/jesseduffield/lazydocker
 ```
 
+### Docker
+
+1. <details><summary>Build it...</summary><p>
+
+    - If you have a x86_64 CPU architecture
+
+        ```sh
+        docker build -t lazydocker . https://github.com/jesseduffield/lazydocker.git
+        ```
+
+    - If you have a ARM 32 bit v6 architecture
+
+        ```sh
+        docker build -t lazydocker \
+        --build-arg BASE_IMAGE_BUILDER=arm32v6/golang \
+        --build-arg BASE_IMAGE=arm32v6/alpine \
+        --build-arg GOARCH=arm \
+        --build-arg GOARM=6 \
+        https://github.com/jesseduffield/lazydocker.git
+        ```
+
+    - If you have a ARM 32 bit v7 architecture
+
+        ```sh
+        docker build -t lazydocker \
+        --build-arg BASE_IMAGE_BUILDER=arm32v7/golang \
+        --build-arg BASE_IMAGE=arm32v7/alpine \
+        --build-arg GOARCH=arm \
+        --build-arg GOARM=7 \
+        https://github.com/jesseduffield/lazydocker.git
+        ```
+
+    - If you have a ARM 64 bit v8 architecture
+
+        ```sh
+        docker build -t lazydocker \
+        --build-arg BASE_IMAGE_BUILDER=arm64v8/golang \
+        --build-arg BASE_IMAGE=arm64v8/alpine \
+        --build-arg GOARCH=arm64 \
+        https://github.com/jesseduffield/lazydocker.git
+        ```
+
+    </p></details>
+1. Run it
+
+    ```sh
+    docker run -it -v /var/run/docker.sock:/var/run/docker.sock lazydocker
+    ```
+
 ## Usage
 
 Call `lazydocker` in your terminal. I personally use this a lot so I've made an alias for it like so: