functional-tests: Show a better error when we can't extract a file
The functional-tests assume that all necessary dependencies are installed. If you are missing one, you'll get an error.
Previously the error looked like this:
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ERROR: nctional-tests/test-extraction-data/images/xmp-loaded-1.expe (__main__.GenericExtractionTestCase)
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Traceback (most recent call last):
File "/home/parallels/newrepos/tracker-miners/tests/functional-tests/common/utils/extractor.py", line 73, in get_tracker_extract_jsonld_output
data = json.loads(output)
File "/usr/lib/python3.6/json/__init__.py", line 354, in loads
return _default_decoder.decode(s)
File "/usr/lib/python3.6/json/decoder.py", line 339, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "/usr/lib/python3.6/json/decoder.py", line 357, in raw_decode
raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "./400-extractor-metadata.py", line 85, in generic_test_extraction
result = get_tracker_extract_jsonld_output(self.file_to_extract)
File "/home/parallels/newrepos/tracker-miners/tests/functional-tests/common/utils/extractor.py", line 76, in get_tracker_extract_jsonld_output
"Output was: %s" % (e, output))
RuntimeError: tracker-extract did not return valid JSON data: Expecting value: line 1 column 1 (char 0)
Output was:
Now it is a bit clearer:
======================================================================
ERROR: nctional-tests/test-extraction-data/images/test-image-1.expe (__main__.GenericExtractionTestCase)
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Traceback (most recent call last):
File "./400-extractor-metadata.py", line 85, in generic_test_extraction
result = get_tracker_extract_jsonld_output(self.file_to_extract)
File "/home/sam/src/tracker-miners/tests/functional-tests/common/utils/extractor.py", line 77, in get_tracker_extract_jsonld_output
"Error output was: %s" % error_output)
RuntimeError: tracker-extract didn't return any data.
Error output was: file:///home/sam/src/tracker-miners/tests/functional-tests/test-extraction-data/images/test-image-1.jpg: No metadata or extractor modules found to handle this file