More helpful error message if checksum of source is missing

[Alexander-Wilms]

When switching a source from git to archive, I forgot to add a sha256. The fedc error message is pretty cryptic, though:

app-id: org.octave.Octave
runtime: org.kde.Sdk
runtime-version: 5.15-23.08
sdk: org.kde.Sdk
modules:

  - name: ghostscript
    sources:
      - type: archive
        url: https://github.com/ArtifexSoftware/ghostpdl-downloads/releases/download/gs10030/ghostpdl-10.03.0.tar.xz
        # sha256: 854fd1958711b9b5108c052a6d552b906f1e3ebf3262763febf347d77618639d
        x-checker-data:
          type: json
          url: https://api.github.com/repos/ArtifexSoftware/ghostpdl-downloads/releases/latest
          version-query: '.name | split(" ") | .[1]'
          url-query: '.assets[] | select(.name|test("^ghostscript-(.*).tar.xz$")) | .browser_download_url'

alexander@PC:~/Technik/Development/flathub/org.octave.Octave> flatpak run org.flathub.flatpak-external-data-checker org.octave.Octave.yaml
Traceback (most recent call last):
  File "/app/bin/flatpak-external-data-checker", line 30, in <module>
    main()
  File "/app/lib/fedc/src/main.py", line 504, in main
    outdated_num, errors_num, updated = asyncio.run(run_with_args(args))
                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/asyncio/runners.py", line 190, in run
    return runner.run(main)
           ^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/asyncio/base_events.py", line 654, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/app/lib/fedc/src/main.py", line 463, in run_with_args
    manifest_checker = manifest.ManifestChecker(args.manifest, options)
                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/app/lib/fedc/src/manifest.py", line 129, in __init__
    self._collect_external_data()
  File "/app/lib/fedc/src/manifest.py", line 179, in _collect_external_data
    self._collect_module_data(self._root_manifest_path, module)
  File "/app/lib/fedc/src/manifest.py", line 239, in _collect_module_data
    self._collect_source_data(module_path, module.get("sources", []), module_obj)
  File "/app/lib/fedc/src/manifest.py", line 251, in _collect_source_data
    self._collect_source_data(
  File "/app/lib/fedc/src/manifest.py", line 295, in _collect_source_data
    data = ExternalBase.from_source(source_path, source, module)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/app/lib/fedc/src/lib/externaldata.py", line 253, in from_source
    return super().from_source(source_path, source, module)  # type: ignore
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/app/lib/fedc/src/lib/externaldata.py", line 172, in from_source
    return data_cls.from_source_impl(source_path, source, module)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/app/lib/fedc/src/lib/externaldata.py", line 346, in from_source_impl
    checksum = MultiDigest.from_source(source)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/app/lib/fedc/src/lib/checksums.py", line 23, in from_source
    assert digests, source
           ^^^^^^^
AssertionError: ordereddict([('type', 'archive'), ('url', 'https://github.com/ArtifexSoftware/ghostpdl-downloads/releases/download/gs10030/ghostpdl-10.03.0.tar.xz'), ('x-checker-data', ordereddict([('type', 'json'), ('url', 'https://api.github.com/repos/ArtifexSoftware/ghostpdl-downloads/releases/latest'), ('version-query', '.name | split(" ") | .[1]'), ('url-query', '.assets[] | select(.name|test("^ghostscript-(.*).tar.xz$")) | .browser_download_url')]))])

With the sha256 specified:

alexander@PC:~/Technik/Development/flathub/org.octave.Octave> flatpak run org.flathub.flatpak-external-data-checker org.octave.Octave.yaml
INFO    src.manifest: Checking 1 external data items
INFO    src.manifest: Started check [1/1] archive ghostscript/ghostpdl-10.03.0.tar.xz (from org.octave.Octave.yaml)
INFO    src.lib.externaldata: Source ghostpdl-10.03.0.tar.xz: got new version 10.03.1
INFO    src.manifest: Finished check [1/1] archive ghostscript/ghostpdl-10.03.0.tar.xz (from org.octave.Octave.yaml)
OUTDATED: ghostpdl-10.03.0.tar.xz
 Has a new version:
  URL:       https://github.com/ArtifexSoftware/ghostpdl-downloads/releases/download/gs10031/ghostscript-10.03.1.tar.xz
  MD5:       248294abc5aee3ca8161012853d73b52
  SHA1:      caa78ad32521b6aace1843e8590fa9c6340de25b
  SHA256:    157212edc96b8ccc409475dce2e49833fb4427f150c455258ded9632c106abee
  SHA512:    59e071cd23aed246b51317d3cccd9ccf8e1e84c4ecf9b22fb938e561eff42cec61915b0bdd96a313a3ea27750579c54ca0d0862b65edd306a621731c0063ffd3
  Size:      68048612
  Version:   10.03.1
  Timestamp: 2024-05-17 11:30:52

INFO    src.main: Check finished with 0 error(s)

[bbhtt]

Linting the manifest is not x-checker's job though, you can use flatpak-builder-lint manifest for that which does proper jsonschema validation of most properties.

Added a basic handling since it reaches the ugly assertion which should not be reached.

[wjt]

Should be solved by #423. Thanks @bbhtt!