GSUtil.py wrapper script

tests/gsutil_test.py

Index: tests/gsutil_test.py
diff --git a/tests/gsutil_test.py b/tests/gsutil_test.py
new file mode 100755
index 0000000000000000000000000000000000000000..0b26be8beaa9ffed0c485833f43bf2c4faaf4da3
--- /dev/null
+++ b/tests/gsutil_test.py
@@ -0,0 +1,172 @@
+#!/usr/bin/env python
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Test gsutil.py."""
+
+
+import __builtin__
+import unittest
+import hashlib
+import zipfile
+import shutil
+import sys
+import base64
+import tempfile
+import json
+import os
+import urllib
+
+
+# Add depot_tools to path
+THIS_DIR = os.path.dirname(os.path.abspath(__file__))
+DEPOT_TOOLS_DIR = os.path.dirname(THIS_DIR)
+sys.path.append(DEPOT_TOOLS_DIR)
+
+import gsutil
+
+
+class TestError(Exception):
+  pass
+
+
+class Buffer(object):
+  def __init__(self):
+    self.data = ''
+
+  def write(self, buf):
+    self.data += buf
+
+  def read(self, amount=None):
+    if not amount:
+      amount = len(self.data)
+    result = self.data[:amount]
+    self.data = self.data[amount:]
+    return result
+
+
+class FakeOpen(object):
+  def __init__(self):
+    self.expectations = []
+
+  def add_expectation(self, filename, data):
+    self.expectations.append((filename, data))
+
+  def urlopen(self, url):
+    exp_url, exp_data = self.expectations.pop(0)
+    if url != exp_url:
+      raise TestError('%s incorrect, expected %s' % (
+          url, exp_url))
+
+    buf = Buffer()
+    buf.write(exp_data)
+    return buf
+
+
+class GsutilUnitTests(unittest.TestCase):
+  def setUp(self):
+    self.fake_open = FakeOpen()
+    self.tempdir = tempfile.mkdtemp()
+    self.old_urlopen = getattr(urllib, 'urlopen')
+    setattr(urllib, 'urlopen', self.fake_open.urlopen)
+
+  def tearDown(self):
+    shutil.rmtree(self.tempdir)
+    setattr(urllib, 'urlopen', self.old_urlopen)
+
+  def test_download_gsutil(self):
+    version = '4.2'
+    filename = 'gsutil_%s.zip' % version
+    full_filename = os.path.join(self.tempdir, filename)
+    fake_file = 'This is gsutil.zip'
+    fake_file2 = 'This is other gsutil.zip'
+    url = '%s%s' % (gsutil.GSUTIL_URL, filename)
+    self.fake_open.add_expectation(url, fake_file)
+
+    self.assertEquals(
+        gsutil.download_gsutil(version, self.tempdir), full_filename)
+    with open(full_filename, 'r') as f:
+      self.assertEquals(fake_file, f.read())
+
+    metadata_url = gsutil.API_URL + filename
+    md5_calc = hashlib.md5()
+    md5_calc.update(fake_file)
+    b64_md5 = base64.b64encode(md5_calc.hexdigest())
+    self.fake_open.add_expectation(metadata_url, json.dumps({
+        'md5Hash': b64_md5
+    }))
+    self.assertEquals(
+        gsutil.download_gsutil(version, self.tempdir), full_filename)
+    with open(full_filename, 'r') as f:
+      self.assertEquals(fake_file, f.read())
+    self.assertEquals(self.fake_open.expectations, [])
+
+    self.fake_open.add_expectation(metadata_url, json.dumps({
+        'md5Hash': base64.b64encode('aaaaaaa')  # Bad MD5
+    }))
+    self.fake_open.add_expectation(url, fake_file2)
+    self.assertEquals(
+        gsutil.download_gsutil(version, self.tempdir), full_filename)
+    with open(full_filename, 'r') as f:
+      self.assertEquals(fake_file2, f.read())
+    self.assertEquals(self.fake_open.expectations, [])
+
+  def test_ensure_gsutil_full(self):
+    version = '4.2'
+    gsutil_dir = os.path.join(self.tempdir, 'gsutil_%s' % version, 'gsutil')
+    gsutil_bin = os.path.join(gsutil_dir, 'gsutil')
+    os.makedirs(gsutil_dir)
+
+    # Mock out call().
+    old_call = getattr(gsutil, 'call')

[dnj, 2014/11/20 19:58:27]

If this test raises an exception, 'call' will stay mocked out. Any reason why
you don't use a mock library, where you can ensure this is undone in 'tearDown'?

[hinoka, 2014/11/20 21:20:15]

My (and Sergey's) experience with mock libraries are they're confusing,
unpredictable, and ultimately easily replaceable with setattr/getattrs.

I'll turn this into a more generic mock.

+    def fake_call(args, **kwargs):
+      self.assertEquals(args, [gsutil_bin, 'version'])
+      self.assertEquals(kwargs, {'verbose': False})
+      raise gsutil.SubprocessError()
+    setattr(gsutil, 'call', fake_call)
+
+    with open(gsutil_bin, 'w') as f:
+      f.write('Foobar')
+    zip_filename = 'gsutil_%s.zip' % version
+    url = '%s%s' % (gsutil.GSUTIL_URL, zip_filename)
+    _, tempzip = tempfile.mkstemp()
+    fake_gsutil = 'Fake gsutil'
+    with zipfile.ZipFile(tempzip, 'w') as zf:
+      zf.writestr('gsutil/gsutil', fake_gsutil)
+    with open(tempzip, 'rb') as f:
+      self.fake_open.add_expectation(url, f.read())
+
+    # This should delete the old bin and rewrite it with 'Fake gsutil'
+    self.assertRaises(
+        gsutil.InvalidGsutilError, gsutil.ensure_gsutil, version, self.tempdir)
+    self.assertTrue(os.path.isdir(os.path.join(self.tempdir, '.cache_dir')))
+    self.assertTrue(os.path.exists(gsutil_bin))
+    with open(gsutil_bin, 'r') as f:
+      self.assertEquals(f.read(), fake_gsutil)
+
+    setattr(gsutil, 'call', old_call)
+
+  def test_ensure_gsutil_short(self):
+    version = '4.2'
+    gsutil_dir = os.path.join(self.tempdir, 'gsutil_%s' % version, 'gsutil')
+    gsutil_bin = os.path.join(gsutil_dir, 'gsutil')
+    os.makedirs(gsutil_dir)
+
+    # Mock out call().
+    old_call = getattr(gsutil, 'call')
+    def fake_call(args, **kwargs):
+      self.assertEquals(args, [gsutil_bin, 'version'])
+      self.assertEquals(kwargs, {'verbose': False})
+      return True
+    setattr(gsutil, 'call', fake_call)
+
+    with open(gsutil_bin, 'w') as f:
+      f.write('Foobar')
+    self.assertEquals(
+        gsutil.ensure_gsutil(version, self.tempdir), gsutil_bin)
+
+    setattr(gsutil, 'call', old_call)
+
+if __name__ == '__main__':
+  unittest.main()