Add a Dockerfile for building a container image (ekzhang#8)

* Add a Dockerfile

* Reduce image size from ~75MB to ~6MB

* Add Dockerignore and README documentation

* Add Docker build action to CI

Co-authored-by: Eric Zhang <ekzhang1@gmail.com>

.dockerignore

@@ -0,0 +1 @@
+/target

.github/workflows/docker.yml

@@ -0,0 +1,49 @@
+name: Docker
+
+on:
+  push:
+    tags:
+      - "v*.*.*"
+
+jobs:
+  build_deploy:
+    name: Build and Deploy
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v3
+        with:
+          images: ekzhang/bore
+          tags: |
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+        with:
+          platforms: arm64
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Build and push
+        id: docker_build
+        uses: docker/build-push-action@v2
+        with:
+          platforms: linux/amd64,linux/arm64,linux/arm/v7
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+
+      - name: Image digest
+        run: echo ${{ steps.docker_build.outputs.digest }}

Dockerfile

@@ -0,0 +1,10 @@
+FROM rust:alpine as builder
+WORKDIR /home/rust/src
+RUN apk --no-cache add musl-dev
+COPY . .
+RUN cargo install --path .
+
+FROM scratch
+COPY --from=builder /usr/local/cargo/bin/bore .
+USER 1000:1000
+ENTRYPOINT ["./bore"]

README.md

@@ -21,6 +21,22 @@ Similar to [localtunnel](https://github.com/localtunnel/localtunnel) and [ngrok]
 
 (`bore` totals less than 400 lines of safe, async Rust code and is trivial to set up — just run a single binary for the client and server.)
 
+## Installation
+
+You can build the `bore` CLI command from source using [Cargo](https://crates.io/), which is bundled with the latest stable Rust toolchain. This command and will install the release `bore` binary at a user-accessible path.
+
+```shell
+cargo install bore-cli
+```
+
+If you have Docker installed on your computer, you can alternatively run the `bore` binary from a minimal "scratch" container.
+
+```shell
+docker run -it --init --rm --network host ekzhang/bore <ARGS>
+```
+
+We publish versioned Docker images for each release, in addition to the `latest` tag. Each image is built for AMD 64-bit, Arm 64-bit, and Armv7 architectures.
+
 ## Detailed Usage
 
 This section describes detailed usage for the `bore` CLI command.