Tests fail with "ImportError: cannot import name 'json_available' from 'flask'"

[sajith]

I am trying to have a GitHub Actions setup going for this repository (current progress here), and there are errors when running tests with Python 3.9:

$ python -m tox
  shell: /usr/bin/bash -e {0}
  env:
    pythonLocation: /opt/hostedtoolcache/Python/3.9.13/x64
    LD_LIBRARY_PATH: /opt/hostedtoolcache/Python/3.9.13/x64/lib

[...]

ERROR: Failure: ImportError (cannot import name 'json_available' from 'flask' (/home/runner/work/sdx-lc/sdx-lc/.tox/py3/lib/python3.9/site-packages/flask/__init__.py))
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/runner/work/sdx-lc/sdx-lc/.tox/py3/lib/python3.9/site-packages/nose/failure.py", line 39, in runTest
    raise self.exc_val.with_traceback(self.tb)
  File "/home/runner/work/sdx-lc/sdx-lc/.tox/py3/lib/python3.9/site-packages/nose/loader.py", line 417, in loadTestsFromName
    module = self.importer.importFromPath(
  File "/home/runner/work/sdx-lc/sdx-lc/.tox/py3/lib/python3.9/site-packages/nose/importer.py", line 47, in importFromPath
    return self.importFromDir(dir_path, fqname)
  File "/home/runner/work/sdx-lc/sdx-lc/.tox/py3/lib/python3.9/site-packages/nose/importer.py", line 94, in importFromDir
    mod = load_module(part_fqname, fh, filename, desc)
  File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/imp.py", line 244, in load_module
    return load_package(name, filename)
  File "/opt/hostedtoolcache/Python/3.9.13/x64/lib/python3.9/imp.py", line 216, in load_package
    return _load(spec)
  File "<frozen importlib._bootstrap>", line 711, in _load
  File "<frozen importlib._bootstrap>", line 680, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 850, in exec_module
  File "<frozen importlib._bootstrap>", line 228, in _call_with_frames_removed
  File "/home/runner/work/sdx-lc/sdx-lc/swagger_server/test/__init__.py", line 4, in <module>
    from flask_testing import TestCase
  File "/home/runner/work/sdx-lc/sdx-lc/.tox/py3/lib/python3.9/site-packages/flask_testing/__init__.py", line 13, in <module>
    from .utils import TestCase, LiveServerTestCase
  File "/home/runner/work/sdx-lc/sdx-lc/.tox/py3/lib/python3.9/site-packages/flask_testing/utils.py", line 38, in <module>
    from flask import json_available, templating, template_rendered
ImportError: cannot import name 'json_available' from 'flask' (/home/runner/work/sdx-lc/sdx-lc/.tox/py3/lib/python3.9/site-packages/flask/__init__.py)

----------------------------------------------------------------------
Ran 1 test in 0.581s

FAILED (errors=1)
ERROR: InvocationError for command /home/runner/work/sdx-lc/sdx-lc/.tox/py3/bin/nosetests (exited with code 1)

[sajith]

This error happens with all Python 3.x versions that I have tested with, except Python 3.10. (There's a different, unrelated error with Python 3.10, and that of course is a different discussion.)

This error happens because Flask 2.0.0 has dropped flask.json_available flag, and flask-testing also have subsequently removed it, here: jarus/flask-testing#136.

Upgrading flask-testing to 0.8.1 should handle this. I wiill make that PR once we have CI running.

[sajith]

This particular error is addressed in PR #17.