git-cl: Make request to upload logs more visible.

Print the message asking the user to upload gerrit logs for git-cl upload
failures after the exception.

Also, initialize the error logger only for git-cl upload, so that the
headers are not overwritten unless git-cl upload is executed again.

Bug: 881860
Change-Id: I8e63432eecca5253e56096e3ad0218eec4058e12
Reviewed-on: https://chromium-review.googlesource.com/c/1277426
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>

gerrit_util.py

@@ -47,6 +47,10 @@ GERRIT_PROTOCOL = 'https'
 # TODO(crbug.com/881860): Remove.
 GERRIT_ERR_LOGGER = logging.getLogger('GerritErrorLogs')
 GERRIT_ERR_LOG_FILE = os.path.join(tempfile.gettempdir(), 'GerritHeaders.txt')
+GERRIT_ERR_MESSAGE = (
+    'If you see this when running \'git cl upload\', please report this to '
+    'https://crbug.com/881860, and attach the failures in %s.\n' %
+    GERRIT_ERR_LOG_FILE)
 INTERESTING_HEADERS = frozenset([
     'x-google-backends',
     'x-google-errorfiltertrace',
@@ -480,15 +484,14 @@ def ReadHttpResponse(conn, accept_statuses=frozenset([200])):
   # end of retries loop
 
   if failed:
-    LOGGER.warn(
-        'If you see this when running \'git cl upload\', consider '
-        'reporting this to https://crbug.com/881860, and please attach the '
-        'failures in %s.\n', GERRIT_ERR_LOG_FILE)
+    LOGGER.warn(GERRIT_ERR_MESSAGE)
   if response.status not in accept_statuses:
     if response.status in (401, 403):
       print('Your Gerrit credentials might be misconfigured. Try: \n'
             '  git cl creds-check')
     reason = '%s: %s' % (response.reason, contents)
+    if failed:
+      reason += '\n' + GERRIT_ERR_MESSAGE
     raise GerritError(response.status, reason)
   return StringIO(contents)
 

git_cl.py

@@ -3170,6 +3170,15 @@ class _GerritChangelistImpl(_ChangelistCodereviewBase):
 
     try:
       # TODO(crbug.com/881860): Remove.
+      # Clear the log after each git-cl upload run by setting mode='w'.
+      handler = logging.FileHandler(gerrit_util.GERRIT_ERR_LOG_FILE, mode='w')
+      handler.setFormatter(logging.Formatter('%(asctime)s %(message)s'))
+
+      GERRIT_ERR_LOGGER.addHandler(handler)
+      GERRIT_ERR_LOGGER.setLevel(logging.INFO)
+      # Don't propagate to root logger, so that logs are not printed.
+      GERRIT_ERR_LOGGER.propagate = 0
+
       # Get interesting headers from git push, to be displayed to the user if
       # subsequent Gerrit RPC calls fail.
       env = os.environ.copy()
@@ -6258,16 +6267,6 @@ class OptionParser(optparse.OptionParser):
         format='[%(levelname).1s%(asctime)s %(process)d %(thread)d '
                '%(filename)s] %(message)s')
 
-    # TODO(crbug.com/881860): Remove.
-    # Clear the log after each git-cl run by setting mode='w'.
-    handler = logging.FileHandler(gerrit_util.GERRIT_ERR_LOG_FILE, mode='w')
-    handler.setFormatter(logging.Formatter('%(asctime)s %(message)s'))
-
-    GERRIT_ERR_LOGGER.addHandler(handler)
-    GERRIT_ERR_LOGGER.setLevel(logging.INFO)
-    # Don't propagate to root logger, so that logs are not printed.
-    GERRIT_ERR_LOGGER.propagate = 0
-
     return options, args