add find_stack_traces tool

this is useful to go and collect all the stack traces found for a
particular test run. Helps us easily identify when stack traces
are being generated even on good runs.

Change-Id: Ia5b95be7bc1a425630fba06c7c65cbaa9fa7079f
diff --git a/tools/find_stack_traces.py b/tools/find_stack_traces.py
new file mode 100755
index 0000000..e6c1990
--- /dev/null
+++ b/tools/find_stack_traces.py
@@ -0,0 +1,83 @@
+#!/usr/bin/env python
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2013 IBM Corp.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.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.
+
+import gzip
+import re
+import StringIO
+import sys
+import urllib2
+
+
+def hunt_for_stacktrace(url):
+    """Return TRACE or ERROR lines out of logs."""
+    page = urllib2.urlopen(url)
+    buf = StringIO.StringIO(page.read())
+    f = gzip.GzipFile(fileobj=buf)
+    content = f.read()
+    traces = re.findall('^(.*? (TRACE|ERROR) .*?)$', content, re.MULTILINE)
+    tracelist = map(lambda x: x[0], traces)
+    # filter out log definitions as false possitives
+    return filter(lambda x: not re.search('logging_exception_prefix', x),
+                  tracelist)
+
+
+def log_url(url, log):
+    return "%s/%s" % (url, log)
+
+
+def collect_logs(url):
+    page = urllib2.urlopen(url)
+    content = page.read()
+    logs = re.findall('(screen-[\w-]+\.txt\.gz)</a>', content)
+    return logs
+
+
+def usage():
+    print """
+Usage: find_stack_traces.py <logurl>
+
+Hunts for stack traces in a devstack run. Must provide it a base log url
+from a tempest devstack run. Should start with http and end with /logs/.
+
+Returns a report listing stack traces out of the various files where
+they are found.
+"""
+    sys.exit(0)
+
+
+def main():
+    if len(sys.argv) == 2:
+        url = sys.argv[1]
+        loglist = collect_logs(url)
+
+        # probably wrong base url
+        if not loglist:
+            usage()
+
+        for log in loglist:
+            logurl = log_url(url, log)
+            traces = hunt_for_stacktrace(logurl)
+            if traces:
+                print "\n\nTRACES found in %s\n" % log
+                for line in traces:
+                    print line
+    else:
+        usage()
+
+if __name__ == '__main__':
+    main()