[lib] Avoid infinite loop on 500 errors in file chooser popup
Traceback (most recent call last):
File "/usr/share/hue/build/env/lib/python3.6/site-packages/django/core/handlers/exception.py", line 47, in inner
response = get_response(request)
File "/usr/share/hue/build/env/lib/python3.6/site-packages/django/utils/deprecation.py", line 114, in __call__
response = response or self.get_response(request)
File "/usr/share/hue/build/env/lib/python3.6/site-packages/django/core/handlers/exception.py", line 49, in inner
response = response_for_exception(request, exc)
File "/usr/share/hue/build/env/lib/python3.6/site-packages/django/core/handlers/exception.py", line 103, in response_for_exception
response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
File "/usr/share/hue/build/env/lib/python3.6/site-packages/django/core/handlers/exception.py", line 142, in handle_uncaught_exception
return callback(request, **param_dict)
File "/usr/share/hue/desktop/core/src/desktop/views.py", line 454, in serve_500_error
return render("500.mako", request, {'traceback': traceback.extract_tb(exc_info[2])})
File "/usr/share/hue/desktop/core/src/desktop/lib/django_util.py", line 239, in render
return render_json(data, request.GET.get("callback"), status=status)
File "/usr/share/hue/desktop/core/src/desktop/lib/django_util.py", line 319, in render_json
json = encode_json(data, indent)
File "/usr/share/hue/desktop/core/src/desktop/lib/django_util.py", line 291, in encode_json
return json.dumps(data, indent=indent, cls=Encoder)
File "/usr/lib/python3.6/json/__init__.py", line 238, in dumps
**kw).encode(obj)
File "/usr/lib/python3.6/json/encoder.py", line 201, in encode
chunks = list(chunks)
File "/usr/lib/python3.6/json/encoder.py", line 430, in _iterencode
yield from _iterencode_dict(o, _current_indent_level)
File "/usr/lib/python3.6/json/encoder.py", line 404, in _iterencode_dict
yield from chunks
File "/usr/lib/python3.6/json/encoder.py", line 325, in _iterencode_list
yield from chunks
File "/usr/lib/python3.6/json/encoder.py", line 437, in _iterencode
o = _default(o)
File "/usr/share/hue/desktop/core/src/desktop/lib/django_util.py", line 89, in default
return json.JSONEncoder.default(self, o)
File "/usr/lib/python3.6/json/encoder.py", line 180, in default
o.__class__.__name__)
TypeError: Object of type 'FrameSummary' is not JSON serializable