Add skeletton for a categorizer plugin #357

Signed-off-by: Philippe Ombredanne <pombredanne@nexb.com>

src/summarycode/plugin_category.py

@@ -0,0 +1,152 @@
+#
+# Copyright (c) 2018 nexB Inc. and others. All rights reserved.
+# http://nexb.com and https://github.com/nexB/scancode-toolkit/
+# The ScanCode software is licensed under the Apache License version 2.0.
+# Data generated with ScanCode require an acknowledgment.
+# ScanCode is a trademark of nexB Inc.
+#
+# You may not use this software except in compliance with the License.
+# You may obtain a copy of the License at: http://apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software distributed
+# under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+# CONDITIONS OF ANY KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations under the License.
+#
+# When you publish or redistribute any data created with ScanCode or any ScanCode
+# derivative work, you must accompany this data with the following acknowledgment:
+#
+#  Generated with ScanCode and provided on an "AS IS" BASIS, WITHOUT WARRANTIES
+#  OR CONDITIONS OF ANY KIND, either express or implied. No content created from
+#  ScanCode should be considered or used as legal advice. Consult an Attorney
+#  for any legal advice.
+#  ScanCode is a free software code scanning tool from nexB Inc. and others.
+#  Visit https://github.com/nexB/scancode-toolkit/ for support and download.
+
+from __future__ import absolute_import
+from __future__ import unicode_literals
+
+import attr
+
+from plugincode.pre_scan import PreScanPlugin
+from plugincode.pre_scan import pre_scan_impl
+from scancode import CommandLineOption
+from scancode import PRE_SCAN_GROUP
+
+# Tracing flag
+TRACE = True
+
+
+def logger_debug(*args):
+    pass
+
+
+if TRACE:
+    import logging
+    import sys
+
+    logger = logging.getLogger(__name__)
+    logging.basicConfig(stream=sys.stdout)
+    logger.setLevel(logging.DEBUG)
+
+    def logger_debug(*args):
+        return logger.debug(' '.join(isinstance(a, unicode) and a or repr(a) for a in args))
+
+"""
+Assign a category to a file.
+
+A category is defined by functions that can check for multiple things such as:
+- file type information (form info)
+- file content
+... and assign a
+
+The known categories are:
+    -
+"""
+
+KNOWN_CATEGORIES = set([
+    'source',
+    'script',
+    'script',
+    'binary',
+    'compiled',
+    'toplevel',
+    'metadata',
+    'build',
+    'tool',
+    'doc',
+    'data',
+    'test',
+    'thirdparty',
+    'legal',
+    'generated',
+])
+
+
+@pre_scan_impl
+class Categorize(PreScanPlugin):
+    """
+    Assign one or more categories to each file or directory.
+    """
+
+    attributes = dict(categories=attr.ib(default=attr.Factory(list)))
+
+    sort_order = 25
+
+    options = [
+        CommandLineOption(('--categorize',),
+           is_flag=True,
+           help='Add categories to files using built-in rules.',
+           help_group=PRE_SCAN_GROUP,
+           sort_order=85,
+        )
+    ]
+
+    def is_enabled(self, categorize, **kwargs):
+        if TRACE:
+            logger_debug('is_enabled: categorize:', categorize)
+        return categorize
+
+    def process_codebase(self, codebase, categorize, **kwargs):
+        """
+        Add categories to resources
+        """
+
+        if not categorize:
+            return
+
+        def update_categories(res, cats):
+            """Update the `res` Resource categories with the `cats` categories."""
+            if res.is_file:
+                updated_categories = set(res.categories)
+                updated_categories.update(cats)
+                updated_categories = sorted(updated_categories)
+                if res.categories != updated_categories:
+                    res.categories = updated_categories
+                    res.save(codebase)
+
+        # Walk the codebase and set the categories for each resource
+        for resource in codebase.walk(topdown=True):
+            categories = get_categories(resource)
+            if not categories:
+                continue
+
+            update_categories(resource, categories)
+
+            for child in resource.children(codebase, categories):
+                update_categories(child)
+
+
+def get_categories(resource, categorizers=()):
+    """
+    Return a sorted list of unique facet strings for `path` using the
+    `facet_definitions` mapping of {pattern: [facet, facet]}.
+    """
+
+    categories = []
+    for categorizer in categorizers:
+        categories.extend(categorizer(resource))
+    return categories
+
+
+
+