构建小容器以运行已编译的go代码

Question

From https://docs.docker.com/articles/baseimages/

I am trying to build a base image to run compiled go code, from: https://github.com/tianon/dockerfiles/tree/master/true

1. I have tried to copy into docker the true.go
   Then: exec: "/true": permission denied
2. Also tried to bash into it, then: "bash"
   Then: executable file not found in $PATH
3. Also tried to use the debootstrap raring raring > /dev/null
   Then: "bash": executable file not found in $PATH

How do you do this?

Thanks

Answer 1

I'm not sure I entirely follow.

The Dockerfile from the linked project builds an image with nothing in it except an executable - there will be no shell or compiler, so running bash will be impossible. It does this by using the special scratch base image, which is simply a completely empty filesystem.

If you clone the repository and build the image using the Dockerfile (docker build -t go-image .), it will simply copy the executable directly into the image (note the Dockerfile copies the executable true-asm, not the source code true.go). If you then use docker run to start the image, it will run it (docker run go-image).

Does that make sense? The code is compiled locally (or by another container) and the compiled, stand-alone executable is placed by itself into the image.

Generally, you don't want to do this and definitely not when you're beginning - it will be easier for you to use a golang or debian image which will include basic tools such as a shell.