在Docker容器中部署Golang应用程序

Question

i need to deploy go restful app into Docker container.

My project has the following structure

go_proj

  |- bin
  |- src |
  |      |- com.example |
  |      |              |- web_service.go
  |      |
  |      |- github.com.gorilla.mux |
  |                                | - ...
  |- Dockerfile

How should my Dockerfile look like? And maybe I should download the library(mux) from the container?

Answer 1

I got some experience with deploying Go apps using Docker.

TL;DR

This is how my project looks like in ${GOPATH}/src/github.com/githubhandle/project

main.go
vendor.conf
vendor/
    github.com/gorilla/mux
    github.com/sirupsen/logrus
    github.com/bshuster-repo/logrus-logstash-hook
    ...
Dockerfile

And the Dockerfile looks like this:

FROM golang:1.8
WORKDIR /go/src/app
COPY . .
RUN go-wrapper download
RUN go-wrapper install
EXPOSE [8080]
ENTRYPOINT ["go-wrapper", "run", "main.go"]

Pretty much

Long answer

In general, I like to put my Dockerfile inside the server directory:

go/
    src/
        github.com/
            mygithub/
                serverproject/
                    main.go
                    Dockerfile

If I am using non standard packages in my projects such as (gorilla/mux) I would probably use vndr to create a vendor directory where I put all these packages and manage their versions.

After that my Dockerfile would probably look like that:

FROM golang:1.8
WORKDIR /go/src/app
COPY . .
RUN go-wrapper download
RUN go-wrapper install
ENTRYPOINT ["go-wrapper", "run", "main.go"]

Note You may want to automatically expose port number. For example, adding this line will expose port 8080 inside the container to the host.

PORT 8080

What is left to do is to build the image from within go/src/github.com/mygithub/serverproject:

docker build -t serverproject .

And to deploy it into a container:

docker run -P --rm --name myserver1 serverproject

If you want to pass arguments to the server you can do that like the following:

docker run -P --rm --name myserver1 serverproject --arg1 --arg2=bla

Note in case you didn't specify PORT in your Dockerfile and would like to expose it to the host, replace -P with -p before --name and specify <host-port>:<container-port>:

docker run --rm -p 8080:8080 ...

This will actually port forward from your host to the container.