Merge pull request #889 from tfranzel/improved_warnings

improve trace messages / warnings & add color #866

README.rst

@@ -156,7 +156,7 @@ Generate your schema with the CLI:
 
 .. code:: bash
 
-    $ ./manage.py spectacular --file schema.yml
+    $ ./manage.py spectacular --color --file schema.yml
     $ docker run -p 80:8080 -e SWAGGER_JSON=/schema.yml -v ${PWD}/schema.yml:/schema.yml swaggerapi/swagger-ui
 
 If you also want to validate your schema add the ``--validate`` flag. Or serve your schema directly

drf_spectacular/contrib/django_filters.py

@@ -57,7 +57,7 @@ def get_schema_operation_parameters(self, auto_schema, *args, **kwargs):
             return []
 
         result = []
-        with add_trace_message(filterset_class.__name__):
+        with add_trace_message(filterset_class):
             for field_name, filter_field in filterset_class.base_filters.items():
                 result += self.resolve_filter_field(
                     auto_schema, model, filterset_class, field_name, filter_field

drf_spectacular/drainage.py

@@ -1,5 +1,6 @@
 import contextlib
 import functools
+import inspect
 import sys
 from collections import defaultdict
 from typing import DefaultDict
@@ -8,9 +9,13 @@
 class GeneratorStats:
     _warn_cache: DefaultDict[str, int] = defaultdict(int)
     _error_cache: DefaultDict[str, int] = defaultdict(int)
+    _blue = ''
+    _red = ''
+    _yellow = ''
+    _clear = ''
 
     def __getattr__(self, name):
-        if not self.__dict__:
+        if 'silent' not in self.__dict__:
             from drf_spectacular.settings import spectacular_settings
             self.silent = spectacular_settings.DISABLE_ERRORS_AND_WARNINGS
         try:
@@ -33,12 +38,25 @@ def reset(self):
         self._warn_cache.clear()
         self._error_cache.clear()
 
+    def enable_color(self):
+        self._blue = '\033[0;34m'
+        self._red = '\033[0;31m'
+        self._yellow = '\033[0;33m'
+        self._clear = '\033[0m'
+
     def emit(self, msg, severity):
         assert severity in ['warning', 'error']
-        msg = _get_current_trace() + str(msg)
         cache = self._warn_cache if severity == 'warning' else self._error_cache
+
+        source_location, breadcrumbs = _get_current_trace()
+        prefix = f'{self._blue}{source_location}: ' if source_location else ''
+        prefix += self._yellow if severity == 'warning' else self._red
+        prefix += f'{severity.capitalize()}'
+        prefix += f' [{breadcrumbs}]: ' if breadcrumbs else ': '
+
+        msg = prefix + self._clear + str(msg)
         if not self.silent and msg not in cache:
-            print(f'{severity.capitalize()} #{len(cache)}: {msg}', file=sys.stderr)
+            print(msg, file=sys.stderr)
         cache[msg] += 1
 
     def emit_summary(self):
@@ -80,17 +98,34 @@ def reset_generator_stats():
 
 
 @contextlib.contextmanager
-def add_trace_message(trace_message):
+def add_trace_message(obj):
     """
     Adds a message to be used as a prefix when emitting warnings and errors.
     """
-    _TRACES.append(trace_message)
+    sourcefile, lineno = _get_source_location(obj)
+    _TRACES.append((sourcefile, lineno, obj.__name__))
     yield
     _TRACES.pop()
 
 
+@functools.lru_cache(maxsize=1000)
+def _get_source_location(obj):
+    try:
+        sourcefile = inspect.getsourcefile(obj)
+        lineno = inspect.getsourcelines(obj)[1]
+        return sourcefile, lineno
+    except:  # noqa: E722
+        return None, None
+
+
 def _get_current_trace():
-    return ''.join(f"{trace}: " for trace in _TRACES if trace)
+    source_locations = [t for t in _TRACES if t[0]]
+    if source_locations:
+        source_location = f"{source_locations[-1][0]}:{source_locations[-1][1]}"
+    else:
+        source_location = ''
+    breadcrumbs = ' > '.join(t[2] for t in _TRACES)
+    return source_location, breadcrumbs
 
 
 def has_override(obj, prop):

drf_spectacular/generators.py

@@ -235,7 +235,7 @@ def parse(self, input_request, public):
                 f'DEFAULT_SCHEMA_CLASS pointing to "drf_spectacular.openapi.AutoSchema" '
                 f'or any other drf-spectacular compatible AutoSchema?'
             )
-            with add_trace_message(getattr(view, '__class__', view).__name__):
+            with add_trace_message(getattr(view, '__class__', view)):
                 operation = view.schema.get_operation(
                     path, path_regex, path_prefix, method, self.registry
                 )

drf_spectacular/management/commands/spectacular.py

@@ -40,13 +40,17 @@ def add_arguments(self, parser):
         parser.add_argument('--validate', dest="validate", default=False, action='store_true')
         parser.add_argument('--api-version', dest="api_version", default=None, type=str)
         parser.add_argument('--lang', dest="lang", default=None, type=str)
+        parser.add_argument('--color', dest="color", default=False, action='store_true')
 
     def handle(self, *args, **options):
         if options['generator_class']:
             generator_class = import_string(options['generator_class'])
         else:
             generator_class = spectacular_settings.DEFAULT_GENERATOR_CLASS
 
+        if options['color']:
+            GENERATOR_STATS.enable_color()
+
         generator = generator_class(
             urlconf=options['urlconf'],
             api_version=options['api_version'],

drf_spectacular/openapi.py

@@ -1497,7 +1497,7 @@ def resolve_serializer(self, serializer, direction, bypass_extensions=False) ->
         assert_basic_serializer(serializer)
         serializer = force_instance(serializer)
 
-        with add_trace_message(serializer.__class__.__name__):
+        with add_trace_message(serializer.__class__):
             component = ResolvedComponent(
                 name=self._get_serializer_name(serializer, direction, bypass_extensions),
                 type=ResolvedComponent.SCHEMA,

tests/test_command.py

@@ -19,7 +19,7 @@ def test_command_plain(capsys):
     assert 'paths' in schema
 
 
-def test_command_parameterized(capsys):
+def test_command_parameterized():
     with tempfile.NamedTemporaryFile() as fh:
         management.call_command(
             'spectacular',
@@ -44,10 +44,25 @@ def test_command_fail(capsys):
             '--urlconf=tests.test_command',
         )
     stderr = capsys.readouterr().err
-    assert 'Error #0: func: unable to guess serializer' in stderr
+    assert 'Error [func]: unable to guess serializer' in stderr
     assert 'Schema generation summary:' in stderr
 
 
+def test_command_color(capsys):
+    management.call_command(
+        'spectacular',
+        '--color',
+        '--urlconf=tests.test_command',
+    )
+    stderr = capsys.readouterr().err
+    assert '\033[0;31mError [func]:' in stderr
+
+    # undo global state change
+    from drf_spectacular.drainage import GENERATOR_STATS
+    GENERATOR_STATS._red = GENERATOR_STATS._blue = ''
+    GENERATOR_STATS._yellow = GENERATOR_STATS._clear = ''
+
+
 def test_command_check(capsys):
     management.call_command('check', '--deploy')
     stderr = capsys.readouterr().err

tests/test_warnings.py

@@ -122,7 +122,9 @@ class XViewset(mixins.ListModelMixin, viewsets.GenericViewSet):
         pass  # pragma: no cover
 
     generate_schema('x', XViewset)
-    assert 'XViewset: exception raised while getting serializer.' in capsys.readouterr().err
+    assert (
+        'Error [XViewset]: exception raised while getting serializer.'
+    ) in capsys.readouterr().err
 
 
 def test_extend_schema_unknown_class(capsys):
@@ -157,7 +159,7 @@ def get(self, request):
             pass  # pragma: no cover
 
     generate_schema('x', view=XView)
-    assert 'XView: unable to guess serializer.' in capsys.readouterr().err
+    assert 'Error [XView]: unable to guess serializer.' in capsys.readouterr().err
 
 
 def test_unable_to_follow_field_source_through_intermediate_property_warning(capsys):
@@ -180,7 +182,7 @@ def get(self, request):
 
     generate_schema('x', view=XAPIView)
     assert (
-        'XAPIView: XSerializer: could not follow field source through intermediate property'
+        '[XAPIView > XSerializer]: could not follow field source through intermediate property'
     ) in capsys.readouterr().err
 
 
@@ -208,8 +210,8 @@ def get(self, request):
 
     generate_schema('x', view=XAPIView)
     stderr = capsys.readouterr().err
-    assert 'XAPIView: XSerializer: unable to resolve type hint for function "x"' in stderr
-    assert 'XAPIView: XSerializer: unable to resolve type hint for function "get_y"' in stderr
+    assert '[XAPIView > XSerializer]: unable to resolve type hint for function "x"' in stderr
+    assert '[XAPIView > XSerializer]: unable to resolve type hint for function "get_y"' in stderr
 
 
 def test_unable_to_traverse_union_type_hint(capsys):