inference-snap-build-and-test

name	inference-snap-build-and-test
description	Build, install, and runtime-verify an inference snap including engine selection and prompt/API checks.
trigger	Keywords like "build check", "pack snap", "install and test", "prompt test", "runtime verification"
scope	user

Inference Snap Build And Test

Purpose

Execute end-to-end verification that the snap builds, installs, starts, and serves prompts correctly.

Host prerequisites (check before building)

snapcraft pack --destructive-mode builds directly on the host, so verify these first and stop-and-report anything missing rather than silently degrading:

• OS: Ubuntu matching the snap base (e.g. core24 ⇒ noble 24.04).

• Tools: snapcraft, snapd active, make, cmake, build-essential, git, plus smoke-test deps curl, jq, ss (iproute2). Install any missing.

• Root: --destructive-mode installs build-packages, so run it under sudo.

• Disk: compute the summed size of the model + all shard/runtime components and require that much free space on the filesystem backing /var/lib/snapd/snaps (where snap install copies artifacts), not just the build dir. A large model can exceed a small container root FS; if so, stop and report that the root FS must be resized (or relocate snapd storage only with explicit approval).

  Approved snapd-storage relocation (workshop containers). When the root FS backing /var/lib/snapd/snaps is too small but a large volume is mounted (typically /project), relocate snapd's snap storage there via a bind-mount before building. This is the established workaround and keeps snap install off the small root FS:

  sudo mkdir -p /project/.snapd-relocate/snaps
  sudo cp -a /var/lib/snapd/snaps/. /project/.snapd-relocate/snaps/   # preserve existing snaps
  sudo mount --bind /project/.snapd-relocate/snaps /var/lib/snapd/snaps
  sudo systemctl restart snapd                                        # re-mount snaps from new backing
  df -h /var/lib/snapd/snaps                                          # confirm large space now visible
  

  snapcraft's own parts/, stage/, prime/ already live in the project dir (on /project), so only snapd's storage needs relocating. Add .snapd-relocate/ to .gitignore. Do this only with the space actually available on the large volume; never modify container configuration.

• GPU: detect /dev/nvidia* / nvidia-smi / /dev/dri. A GPU engine can only be smoke-tested if the matching hardware is present; otherwise it will report compatible: false and is skipped (not a failure).

Model preparation (before packing)

The model artifacts are not committed. Before snapcraft pack, run the repo's model preparation (typically ./download-models.sh, which may wrap make download-models && make split-model) so the component payloads exist on disk. For sharded models, confirm every shard landed in its component directory with the exact filename the model.yaml layout expects.

Required Workflow

1. Build and pack:
   • Run: snapcraft pack --destructive-mode
   • Do not use any other command to build or pack the snap, as it may not produce the expected artifacts.
2. Install artifacts:
   • Run: sudo snap install *.snap *.comp --dangerous
3. Connect required interfaces:
   • Run: sudo snap connect :
   • Required interfaces include:
     • hardware-observe
     • opengl
     • network-bind
     • process-control
     • Any additional interfaces declared in snapcraft.yaml.
4. Smoke test the snap:
   • The snap should already be running after installation on the host machine. Check with: sudo status.
   • Clone the repository https://github.com/canonical/inference-snaps-dev and switch to branch v2
   • Use the smoke-test.sh script to verify the snap.
   • Confirm the script output indicates successful execution.
   • If the script fails, report the exact failing command and output, and apply a patch with the smallest viable fix
   • If the script passes, proceed to the next step.
   • Discover which are compatible by running <snap-name> list-engines --format json. Check the key compatible in the output for each engine.
   • Repeat the smoke test for each compatible engine.

Rules

• Do not declare success without a real smoke test pass.
• Include exact failing command/output summary when blocked.
• Re-run the failed verification step after each fix.
• Do not change the testing script smoke-test.sh.