Building Weave Net

You only need to build Weave Net if you want to work on the Weave Net codebase (or you just enjoy building software).

Apart from the weave shell script, Weave Net is delivered as a set of container images. There is no distribution-specific packaging, so in principle it shouldn’t matter which Linux distribution you build under. But naturally, Docker is a prerequisite (version 1.12.0 or later).

**Note:** The following information is now obsolete. Weave Net is
now maintained by the community, and one of the first things that
changed in this model was the build process. The new process is
still being fine-tuned, and will be documented here once done. In
the meantime, you can look at [https://github.com/rajch/weave/blob/master/reweave/BUILDING.md](https://github.com/rajch/weave/blob/master/reweave/BUILDING.md) 
to see the current state of the process.

The current documentation is being kept in for now, until it can be replaced.

The only way to build is by using the the build container; the Makefile is setup to make this transparent. This method is documented below, and can be run directly on your machine or using a Vagrant VM.

Building directly on your machine

The weave git repository should be cloned into $GOPATH/src/github.com/weaveworks/weave, in accordance with the Go workspace conventions:

$ WEAVE=github.com/weaveworks/weave
$ git clone https://$WEAVE $GOPATH/src/$WEAVE
$ cd $GOPATH/src/$WEAVE
$ git submodule update --init

Next install Docker if you haven’t already, by following the instructions on the Docker site.

Then to actually build, simply do:

$ make

On a fresh repository, the Makefile will do the following:

assemble the build container
download specific versions of all the dependencies
build the weave components in the build container
package them into two Docker images (weaveworks/weave, weaveworks/weaveexec)
export these images as weave.tar.gz.

The first two steps may take a while - don’t worry, they are are cached and should not need to be redone very often.

Building using Vagrant

If you aren’t running Linux, or otherwise don’t want to run the Docker daemon outside a VM, you can use Vagrant to run a development environment. You’ll probably need to install VirtualBox too, for Vagrant to run VMs in.

First, check out the code:

$ git clone https://github.com/weaveworks/weave
$ cd weave
$ git submodule update --init

The Vagrantfile in the top directory constructs a VM that has:

Docker installed
Go tools installed
Weave’s dependencies installed
$GOPATH set to ~
the local working directory mapped as a synced folder into the right place in $GOPATH.

Once you are in the working directory you can issue:

$ vagrant up

and wait for a while (don’t worry, the long download and package installation is done just once). The working directory is sync’ed with ~/src/github.com/weaveworks/weave on the VM, so you can edit files and use git and so on in the regular filesystem.

To build and run the code, you need to use the VM. To log in and build the weave image, do:

$ vagrant ssh
vm$ cd src/github.com/weaveworks/weave
vm$ make

The Docker daemon is also running in this VM, so you can then do:

vm$ sudo ./weave launch
vm$ sudo docker ps

and so on.

If you are looking to just do a build and not run anything on this VM, you can do so with:

$ vagrant ssh -c 'make -C src/github.com/weaveworks/weave'

you should then find a weave.tar.gz container snapshot tarball in the top-level directory. You can use that snapshot with docker load against a different host, e.g.:

$ export DOCKER_HOST=tcp://<HOST:PORT>
$ docker load < weave.tar.gz

You can provide extra Vagrant configuration by putting a file Vagrant.local in the same place as Vagrantfile; for instance, to forward additional ports.