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Building go-lang project /Kubernetes Ingress/ from scratch with no go experience

I have been working with Kubernetes and I wanted to build it's contrib yesterday. However, nginx implementation of Kubernetes' Ingress is written in go-lang. Even though I needed to change some const string, it required recompilation.

Go is not java, and go building system is not maven. Setting up the environment was not straightforward. I was facing couple troubles but I'm going to take it from the beginning. My laptop uses ubuntu 15.04 - well 15.10 since 9pm :-) - and I have never installed go lang yet.

Go lang installation on Ubuntu

First of all, you need to install go lang. You can use official repo, but it contains older version 1.3. However, do not install it using apt-get as kubernetes or it's dependencies require higher version of go-lang. Of course, I originally installed version 1.3  but some fatal error occurred later. It forced me do to the manual installation anyway.

Here is simple tutorial.


Last two lines affect only the current terminal. You should update /etc/environment in the case you consider to use go-lang in the future.

Then, you can try to get version of go via:

$ go version
go version go1.5.1 linux/amd64

Go-lang compilation and building


Now, you can pull your git project, e.g.:

git clone https://github.com/kubernetes/contrib

There is a build command in go-lang. You can type it into you terminal:


What's wrong? We have not setup GOPATH yet. This directory is something like maven cache. It's pretty simple, you can just point the variable to your home, e.g.
export GOPATH=/home/martin/.go
Try to build it again. There are no errors, but nothing is happening. I found in some stackoverflow discussion that there is a get command as well. Unfortunately, build is consist of get anyway. Then I found -v as verbose.


Actually, we are on right track. The fetching of dependencies takes a time so it seemed that go build or go get did not work but that's not true.

That's all, now building should work:


Go-lang 1.3 vs 1.5

I just wanted to discuss why to prefer manual installation over ubuntu repository. For the record. Building kubernetes project using go-lang 1.3 from ubuntu official repo failed:

Comments

I'm facing the same error: undefined: crypto.Signer
where you able to get this resolved ?

Thanks!
hi, I was able to get get pass the undefined: cryto.Signer error.

This error is fixed by upgrading Go to at least 1.4.
go get -v golang.org/x/crypto/ssh

Incase you get this error after upgrade:
import /home/stack/mygo/pkg/linux_amd64/golang.org/x/crypto/curve25519.a: object is [linux amd64 go1.2.1 X:none] expected [linux amd64 go1.6 X:none]

Remove the previous ssh package files, should work then.

Thanks!
James Jiang said…
Thank you very much for this, saved my day at the 'go get -v' command - forgive I'm totally 0 knowledge about go. Was trying hard to let the 'godep' and Makefile work, but turned out go build should just do the job.

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