Go environment setup

2012-02-27T08:37:00.000+01:00

A good start for Go development is a root directory for all further directories like /home/themue/projects. It will be the home for the Go SDK, 3rd party packages and own projects. The current weekly will be installed with the command hg clone -u weekly https://code.google.com/p/go in the directory go. http://weekly.golang.org/doc/install.html documents all needed steps in detail. The two other directories have to be created by hand, together with a src and a pkg subdirectory each. This way you get the structure

/home/themue/projects
/go
/bin
...
/test
/own
/pkg
/src
/3rdparty
/pkd
/src

Why this 3rd party directory? The new Go tools have a very intelligent way to install external packages in a different directory than own packages. It's based on the environment variable $GOPATH. The naming already shows that it's a path, not only one directory. $GOPATH is the path where commands like go build and go install look for referenced packages they need to compile and link the software. To do so external packages have to be installed before. The command go get will install the sources and the compiled package into the first directory of the path. So the order in the case above should be

GOPATH=$HOME/projects/3rdparty:$HOME/projects/own

When installing own packages which source is located in .../own/src it will be installed into .../own/pkg.

Which environment variables else are needed? One is $GOROOT. It has to point to the root of the Go SDK, here /home/themue/projects/go. The compiled binaries will by default be installed in $GOROOT/bin. But there are two further options for the work with the SDK:

The location for the binaries is ok. Here the standard $PATH should point to this directory too with PATH=$PATH:$HOME/projects/go/bin.
The other way is that you've got a directory like $HOME/bin for all your private binaries and scripts and it's already in your $PATH. In this case you can set GOBIN=$HOME/bin before installing the Go SDK. In this case after the compilation the Go binaries get installed in your $HOME/bin.

Inside your own source directory you may need further subdirectories for your different projects. Their naming depends on possible external SCM environments you're using. Mine is code.google.com. So for the Tideland Common Go Library (see http://code.google.com/p/tcgl) I placed the source in
.../own/src/code.google.com/p/tcgl. This project contains several packages which I now can import as code.google.com/p/tcgl/foo, regardless if I'm inside the same project or another one. And more important is that people who are taking a look into my code can easily see how to get and import it as their 3rd party code.

Restart of this blog

2012-02-26T20:39:00.001+01:00

So, re-started this blog. It is now hosted at blogger.com and focussed on software development. Privat topics are handled at frank.mweb.de. But that blog is in German. The first topics are in the pipe, so stay tuned.

embrace change

Go environment setup

Restart of this blog