add verbose and quiet options to command line for debugging

Also set up scanner tests to capture the logging output.

Change-Id: Ib8def5082bb50b019a2f7b8772314dd2f5bd5589

releasenotes/notes/add-verbose-flag-88d72cb01812c616.yaml

@@ -0,0 +1,3 @@
+---
+features:
+  - Add the ``--verbose``, ``-v``, and ``-q`` options to the command line tool for producing different levels of debug output.

reno/lister.py

@@ -12,12 +12,17 @@
 
 from __future__ import print_function
 
+import logging
+
 from reno import scanner
 from reno import utils
 
+LOG = logging.getLogger(__name__)
+
 
 def list_cmd(args):
     "List notes files based on query arguments"
+    LOG.debug('starting list')
     reporoot = args.reporoot.rstrip('/') + '/'
     notesdir = utils.get_notes_dir(args)
     notes = scanner.get_notes_by_version(reporoot, notesdir, args.branch)

reno/main.py

@@ -11,6 +11,7 @@
 # under the License.
 
 import argparse
+import logging
 import sys
 
 from reno import create
@@ -21,6 +22,21 @@ from reno import report
 
 def main(argv=sys.argv[1:]):
     parser = argparse.ArgumentParser()
+    parser.add_argument(
+        '-v', '--verbose',
+        dest='verbosity',
+        default=logging.INFO,
+        help='produce more output',
+        action='store_const',
+        const=logging.DEBUG,
+    )
+    parser.add_argument(
+        '-q', '--quiet',
+        dest='verbosity',
+        action='store_const',
+        const=logging.WARN,
+        help='produce less output',
+    )
     parser.add_argument(
         '--rel-notes-dir', '-d',
         dest='relnotesdir',
@@ -89,4 +105,10 @@ def main(argv=sys.argv[1:]):
     do_report.set_defaults(func=report.report_cmd)
 
     args = parser.parse_args()
+
+    logging.basicConfig(
+        level=args.verbosity,
+        format='%(message)s',
+    )
+
     return args.func(args)

reno/scanner.py

@@ -13,6 +13,7 @@
 from __future__ import print_function
 
 import collections
+import logging
 import os.path
 import re
 import subprocess
@@ -21,6 +22,7 @@ import sys
 from reno import utils
 
 _TAG_PAT = re.compile('tag: ([\d\.]+)')
+LOG = logging.getLogger(__name__)
 
 
 def _get_current_version(reporoot, branch=None):
@@ -87,13 +89,15 @@ def get_notes_by_version(reporoot, notesdir, branch=None):
     they were available, regardless of whether they changed later.
     """
 
+    LOG.debug('scanning %s/%s (branch=%s)' % (reporoot, notesdir, branch))
+
     versions = []
     earliest_seen = collections.OrderedDict()
 
     # Determine the current version, which might be an unreleased or dev
     # version.
     current_version = _get_current_version(reporoot, branch)
-    # print('current_version = %s' % current_version)
+    LOG.debug('current repository version: %s' % current_version)
 
     # Remember the most current filename for each id, to allow for
     # renames.
@@ -105,6 +109,7 @@ def get_notes_by_version(reporoot, notesdir, branch=None):
     if branch is not None:
         log_cmd.append(branch)
     log_cmd.extend(['--', notesdir + '/*.yaml'])
+    LOG.debug('running %s' % ' '.join(log_cmd))
     history_results = utils.check_output(log_cmd, cwd=reporoot)
     history = history_results.split('\x00')
     current_version = current_version
@@ -121,34 +126,43 @@ def get_notes_by_version(reporoot, notesdir, branch=None):
         sha = hlines[0].split(' ')[0]
         tags = _TAG_PAT.findall(hlines[0])
         filenames = hlines[2:]
+        LOG.debug('%s contains files %s' % (sha, filenames))
 
         # If there are no tags in this block, assume the most recently
         # seen version.
         if not tags:
+            LOG.debug('%s is untagged, using %s' % (sha, current_version))
             tags = [current_version]
         else:
             current_version = tags[0]
+            LOG.debug('%s has tags, updating current version to %s' %
+                      (sha, current_version))
 
         # Remember each version we have seen.
         if current_version not in versions:
+            LOG.debug('%s is a new version' % current_version)
             versions.append(current_version)
 
         # Remember the files seen, using their UUID suffix as a unique id.
         for f in filenames:
             # Updated as older tags are found, handling edits to release
             # notes.
+            LOG.debug('setting earliest reference to %s to %s' %
+                      (f, tags[0]))
             uniqueid = _get_unique_id(f)
             earliest_seen[uniqueid] = tags[0]
             if uniqueid in last_name_by_id:
                 # We already have a filename for this id from a
                 # new commit, so use that one in case the name has
                 # changed.
+                LOG.debug('%s was seen before' % f)
                 continue
             if _file_exists_at_commit(reporoot, f, sha):
                 # Remember this filename as the most recent version of
                 # the unique id we have seen, in case the name
                 # changed from an older commit.
                 last_name_by_id[uniqueid] = (f, sha)
+                LOG.debug('remembering %s as filename for %s' % (f, uniqueid))
 
     # Invert earliest_seen to make a list of notes files for each
     # version.

reno/tests/test_scanner.py

@@ -13,6 +13,7 @@
 # under the License.
 
 import itertools
+import logging
 import os.path
 import re
 import subprocess
@@ -156,6 +157,13 @@ class Base(base.TestCase):
 
     def setUp(self):
         super(Base, self).setUp()
+        self.logger = self.useFixture(
+            fixtures.FakeLogger(
+                format='%(levelname)8s %(name)s %(message)s',
+                level=logging.DEBUG,
+                nuke_handlers=True,
+            )
+        )
         # Older git does not have config --local, so create a temporary home
         # directory to permit using git config --global without stepping on
         # developer configuration.