Installation from source (git) error: snapcraft validation file is missing from installation path

[Simos Xenitellis ]

When trying to install snapcraft from source, there are a few rough edges and in the end snapcraft will not work because the snapcraft validation file is not placed in the correct location.

Specifically,

1. Create a new LXD container (lxc launch ubuntu:x snaps)
2. Enter the container
    lxc exec snaps -- /bin/bash
3. Install the dependency packages
    apt update
    apt upgrade -y
    apt build-dep snapcraft

4. Get the source of snapcraft,

     git clone https://github.com/snapcore/snapcraft.git

5. Build and install

    cd snapcraft/
    python3 setup.py build
    python3 setup.py install

6. Test the newly install snapcraft

# mkdir mytest
# cd mytest
# snapcraft init
# snapcraft
Issues while validating snapcraft.yaml: snapcraft validation file is missing from installation path

WHAT SHOULD HAVE HAPPENED: snapcraft should have created the null snap.
WHAT HAPPENS: snapcraft cannot find the schema "snapcraft.yaml".

Specifically, snapcraft (installed from source) tries to find the schema snapcraft.yaml in /usr/share/snapcraft/schema/snapcraft.yaml
However, the schema is installed in
/usr/local/lib/python3.5/dist-packages/snapcraft-2.25-py3.5.egg/share/snapcraft/schema/snapcraft.yaml

[Jan (5-jan-h)]

Workaround that works for me:

sudo ln -s /usr/local/lib/python3.5/dist-packages/snapcraft-2.28-py3.5.egg/share/snapcraft/ /usr/share/snapcraft

[Kyle Fazzari (kyrofa)]

Sorry for the delay on this, Simos. The proposed fix is here: https://github.com/snapcore/snapcraft/pull/1356 . Would you mind testing it out?

[Simos Xenitellis  (simosx)]

I have tested the new change and it works OK now.

1. I followed the Hacking guide to install snapcraft (instead of my original report's notes).
2. I used a clean 16.04 LXD container for the testing.
3. I applied the patch from the github pull request.

The variables that common.py touches, have been updated to

/home/ubuntu/venv/snapcraft/share/snapcraft/plugins
/home/ubuntu/venv/snapcraft/share/snapcraft/schema
/home/ubuntu/venv/snapcraft/share/snapcraft/libraries
/home/ubuntu/venv/snapcraft/share/snapcraft/tour

And here is the output of the creation of the null snap,

$ snapcraft
Preparing to pull my-part
Pulling my-part
Preparing to build my-part
Building my-part
Staging my-part
Priming my-part
Snapping 'my-snap-name' |
Snapped my-snap-name_0.1_amd64.snap
$ _

[Kyle Fazzari (kyrofa)]

Thanks so much for testing, Simos!