Snappy is part of Ubuntu Core and enables a fully transactional Ubuntu system.
When working with the source of Go programs, you should define a path within
your home directory (or other workspace) which will be your GOPATH. GOPATH
is similar to Java's CLASSPATH or Python's ~/.local. GOPATH is documented
http://golang.org/pkg/go/build/ and inside the go tool itself
go help gopath
Various conventions exist for naming the location of your GOPATH, but it
should exist, and be writable by you. For example
export GOPATH=${HOME}/work
mkdir $GOPATH
will define and create $HOME/work as your local GOPATH. The go tool
itself will create three subdirectories inside your GOPATH when required;
src, pkg and bin, which hold the source of Go programs, compiled packages
and compiled binaries, respectively.
Setting GOPATH correctly is critical when developing Go programs. Set and
export it as part of your login script.
Add $GOPATH/bin to your PATH, so you can run the go programs you install:
PATH="$PATH:$GOPATH/bin"
The easiest way to get the source for snappy is to use the go get command.
go get -d -v github.com/snapcore/snapd/...
This command will checkout the source of snappy and inspect it for any unmet
Go package dependencies, downloading those as well. go get will also build
and install snappy and its dependencies. To checkout without installing, use
the -d flag. More details on the go get flags are available using
go help get
At this point you will have the git local repository of the snappy source at
$GOPATH/github.com/snapcore/snapd. The source for any
dependent packages will also be available inside $GOPATH.
To generate dependencies.tsv you need godeps, so
go get launchpad.net/godeps
To obtain the correct dependencies for the project, run:
godeps -t -u dependencies.tsv
You can use the script get-deps.sh to run the two previous steps.
If the dependencies need updating
godeps -t ./... > dependencies.tsv
To build, once the sources are available and GOPATH is set, you can just run
go build -o /tmp/snap github.com/snapcore/snapd/cmd/snap
to get the snap binary in /tmp (or without -o to get it in the current
working directory). Alternatively:
go install github.com/snapcore/snapd/...
to have it available in $GOPATH/bin
Contributions are always welcome! Please make sure that you sign the Canonical contributor licence agreement at http://www.ubuntu.com/legal/contributors
Snappy can be found on Github, so in order to fork the source and contribute, go to https://github.com/snapcore/snapd. Check out Github's help pages to find out how to set up your local branch, commit changes and create pull requests.
We value good tests, so when you fix a bug or add a new feature we highly encourage you to create a test in $source_testing.go. See also the section about Testing.
To run the various tests that we have to ensure a high quality source just run:
./run-checks
This will check if the source format is consistent, that it build, all tests work as expected and that "go vet" and "golint" have nothing to complain.
You can run individual test with:
go test -check.f $testname
If a test hangs, you can enable verbose mode:
go test -v -check.vv
(or -check.v for less verbose output).
There is more to read about the testing framework on the website
To test the snapd REST API daemon on a snappy system you need to
transfer it to the snappy system and then run:
sudo systemctl stop snapd.service snapd.socket
sudo /lib/systemd/systemd-activate -E SNAPD_DEBUG=1 -l /run/snapd.socket ./snapd
This will stop the installed snapd and activate the new one. Once it's
printed out something like Listening on /run/snapd.socket as 3. you
should then
sudo chmod 0666 /run/snapd.socket
so the socket has the right permissions (otherwise you need sudo to
connect).