Add retry logic to install-sysroot.py

build/linux/sysroot_scripts/install-sysroot.py

Index: build/linux/sysroot_scripts/install-sysroot.py
diff --git a/build/linux/sysroot_scripts/install-sysroot.py b/build/linux/sysroot_scripts/install-sysroot.py
index dc492c6a56efb84de9ccef7f9acfb0c20025a13d..e342364c1cd22f991e6efebb9cc58c0dfbad93cd 100755
--- a/build/linux/sysroot_scripts/install-sysroot.py
+++ b/build/linux/sysroot_scripts/install-sysroot.py
@@ -24,6 +24,7 @@ import re
 import shutil
 import subprocess
 import sys
+import time
 
 SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
 sys.path.append(os.path.dirname(os.path.dirname(SCRIPT_DIR)))
@@ -135,7 +136,14 @@ def InstallDefaultSysroots():
     InstallSysroot(target_arch)
 
 
-def main():
+def main(args):
+  parser = optparse.OptionParser('usage: %prog [OPTIONS]', description=__doc__)
+  parser.add_option('--running-as-hook', action='store_true',
+                    default=False, help='Used when running from gclient hooks.'
+                                        ' Installs default sysroot images.')
+  parser.add_option('--arch', type='choice', choices=valid_archs,
+                    help='Sysroot architecture: %s' % ', '.join(valid_archs))
+  options, _ = parser.parse_args(args)
   if options.running_as_hook and not sys.platform.startswith('linux'):
     return 0
 
@@ -143,13 +151,35 @@ def main():
     InstallDefaultSysroots()
   else:
     if not options.arch:
-      print 'You much specify either --arch or --running-as-hook'
-      return 1
+      raise Error('You much specify either --arch or --running-as-hook')
     InstallSysroot(options.arch)
 
   return 0
 
 
+def DownloadURL(url, filename):
+  print 'Downloading %s' % url
+  sys.stdout.flush()
+  sys.stderr.flush()
+
+  # Re-try download in order to mitigate network falkiness.

[Lei Zhang, 2016/02/17 20:49:51]

typo

+  num_retries = 3
+  retry_wait = 5  # Doubled at each retry.
+  cmd = ['curl', '--fail', '-L', url, '-o', filename]
+  while True:
+    rtn = subprocess.call(cmd)
+    if rtn == 0:
+      return
+    elif num_retries:

[Lei Zhang, 2016/02/17 20:49:51]

no elif / else after a return.

+      # Curl failed.  Retry
+      print 'Retrying in %d s ...' % retry_wait
+      time.sleep(retry_wait)
+      num_retries -= 1
+      retry_wait *= 2
+    else:
+      raise Error('download command failed (%s): %s' % (rtn, cmd))

[Lei Zhang, 2016/02/17 20:49:51]

%s seems to work, but shouldn't it be %d since |rtn| is an int?

+
+
 def InstallSysroot(target_arch):
   # The sysroot directory should match the one specified in build/common.gypi.
   # TODO(thestig) Consider putting this else where to avoid having to recreate
@@ -193,10 +223,7 @@ def InstallSysroot(target_arch):
     shutil.rmtree(sysroot)
   os.mkdir(sysroot)
   tarball = os.path.join(sysroot, tarball_filename)
-  print 'Downloading %s' % url
-  sys.stdout.flush()
-  sys.stderr.flush()
-  subprocess.check_call(['curl', '--fail', '-L', url, '-o', tarball])
+  DownloadURL(url, tarball)
   sha1sum = GetSha1(tarball)
   if sha1sum != tarball_sha1sum:
     raise Error('Tarball sha1sum is wrong.'
@@ -209,11 +236,8 @@ def InstallSysroot(target_arch):
 
 
 if __name__ == '__main__':
-  parser = optparse.OptionParser('usage: %prog [OPTIONS]', description=__doc__)
-  parser.add_option('--running-as-hook', action='store_true',
-                    default=False, help='Used when running from gclient hooks.'
-                                        ' Installs default sysroot images.')
-  parser.add_option('--arch', type='choice', choices=valid_archs,
-                    help='Sysroot architecture: %s' % ', '.join(valid_archs))
-  options, _ = parser.parse_args()
-  sys.exit(main())
+  try:
+    sys.exit(main(sys.argv[1:]))
+  except Error as e:
+    sys.stderr.write(str(e) + '\n')
+    sys.exit(1)