[infra] gcb: Add cancel.py

Also recognize CANCELLED status in wait_for_build.

infra/gcb/cancel.py

@@ -0,0 +1,41 @@
+#!/usr/bin/python2
+
+"""Cancels project build on Google Cloud Builder.
+
+Usage: cancel.py <build_id>
+"""
+
+import base64
+import collections
+import datetime
+import os
+import subprocess
+import sys
+import time
+import urllib
+import yaml
+
+from oauth2client.client import GoogleCredentials
+from oauth2client.service_account import ServiceAccountCredentials
+from googleapiclient.discovery import build
+
+def usage():
+  sys.stderr.write(
+    "Usage: " + sys.argv[0] + " <build_id>\n")
+  exit(1)
+
+
+def main():
+  if len(sys.argv) != 2:
+    usage()
+
+  build_id = sys.argv[1]
+
+  credentials = GoogleCredentials.get_application_default()
+  cloudbuild = build('cloudbuild', 'v1', credentials=credentials)
+  print cloudbuild.projects().builds().cancel(
+      projectId='clusterfuzz-external', id=build_id, body={}).execute()
+
+
+if __name__ == "__main__":
+  main()

infra/gcb/wait_for_build.py

@@ -12,7 +12,6 @@ import datetime
 from googleapiclient.discovery import build
 from oauth2client.client import GoogleCredentials
 
-
 POLL_INTERVAL = 15
 cloudbuild = None
 
@@ -29,7 +28,12 @@ def get_build(build_id, cloudbuild):
 
 
 def wait_for_build(build_id):
-  global cloudbuild
+  DONE_STATUSES = [
+      'SUCCESS',
+      'FAILURE',
+      'INTERNAL_ERROR',
+      'CANCELLED',
+  ]
 
   status = None
   while True:
@@ -40,7 +44,7 @@ def wait_for_build(build_id):
         print datetime.datetime.now(), current_status
         sys.stdout.flush()
     status = current_status
-    if status == 'SUCCESS' or status == 'FAILURE' or status == 'INTERNAL_ERROR':
+    if status in DONE_STATUSES:
       return status == 'SUCCESS'
 
     time.sleep(POLL_INTERVAL)