docker: add Dockerfile (#14)

Add docker file and describe how to use dockerized boa.

Dockerfile

@@ -0,0 +1,17 @@
+FROM golang:latest as builder
+
+WORKDIR /boa
+COPY go.mod go.sum ./
+RUN go mod download
+COPY . .
+RUN go build -o ./boa ./cmd/boa
+
+FROM golang:latest
+LABEL maintainer="Dominik Roos <[email protected]>"
+
+ARG WORKDIR=/workdir
+RUN mkdir -p ${WORKDIR}
+WORKDIR /workdir
+COPY --from=builder /boa/boa /usr/local/bin
+
+ENTRYPOINT ["boa"]

README.md

@@ -16,6 +16,18 @@ A venom-free generator for cobra applications.
 go get -u github.com/oncilla/boa/cmd/boa
 ```
 
+## Docker
+
+If you prefer using docker instead:
+
+```txt
+WORKDIR=$(pwd)/path/to/application
+docker run \
+    -v $WORKDIR/:/workdir \
+    --user "$(id -u):$(id -g)" \
+    docker.pkg.github.com/oncilla/boa/boa:latest
+```
+
 ## Getting started
 
 `boa` proposes a different layout than what `cobra` proposes as a [typical