Make swift-form-signature testable

Moved the body of bin/swift-form-signature into
swift/cli/form_signature.py, like was done with swift-ring-builder and
others. Added a couple basic tests; there's not 100% coverage, but
it's better than the 0% coverage we had before.

It's almost a straight forklift, but I changed exit() calls to return
statements.

Change-Id: Ie2f702c070da24d9cdface83b9e838e9e2965085

3 files changed, 160 insertions, 67 deletions

diff --git a/bin/swift-form-signature b/bin/swift-form-signature
index 91c76699f..15a077791 100755
--- a/bin/swift-form-signature
+++ b/bin/swift-form-signature
@@ -12,72 +12,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import hmac
-from hashlib import sha1
-from os.path import basename
-from sys import argv, exit
-from time import time
+import sys
+import swift.cli.form_signature
 
 
-if __name__ == '__main__':
-    if len(argv) != 7:
-        prog = basename(argv[0])
-        print 'Syntax: %s <path> <redirect> <max_file_size> ' \
-              '<max_file_count> <seconds> <key>' % prog
-        print
-        print 'Where:'
-        print '  <path>            The prefix to use for form uploaded'
-        print '                    objects. For example:'
-        print '                    /v1/account/container/object_prefix_ would'
-        print '                    ensure all form uploads have that path'
-        print '                    prepended to the browser-given file name.'
-        print '  <redirect>        The URL to redirect the browser to after'
-        print '                    the uploads have completed.'
-        print '  <max_file_size>   The maximum file size per file uploaded.'
-        print '  <max_file_count>  The maximum number of uploaded files'
-        print '                    allowed.'
-        print '  <seconds>         The number of seconds from now to allow'
-        print '                    the form post to begin.'
-        print '  <key>             The X-Account-Meta-Temp-URL-Key for the'
-        print '                    account.'
-        print
-        print 'Example output:'
-        print '    Expires: 1323842228'
-        print '  Signature: 18de97e47345a82c4dbfb3b06a640dbb'
-        exit(1)
-    path, redirect, max_file_size, max_file_count, seconds, key = argv[1:]
-    try:
-        max_file_size = int(max_file_size)
-    except ValueError:
-        max_file_size = -1
-    if max_file_size < 0:
-        print 'Please use a <max_file_size> value greater than or equal to 0.'
-        exit(1)
-    try:
-        max_file_count = int(max_file_count)
-    except ValueError:
-        max_file_count = 0
-    if max_file_count < 1:
-        print 'Please use a positive <max_file_count> value.'
-        exit(1)
-    try:
-        expires = int(time() + int(seconds))
-    except ValueError:
-        expires = 0
-    if expires < 1:
-        print 'Please use a positive <seconds> value.'
-        exit(1)
-    parts = path.split('/', 4)
-    # Must be four parts, ['', 'v1', 'a', 'c'], must be a v1 request, have
-    # account and container values, and optionally have an object prefix.
-    if len(parts) < 4 or parts[0] or parts[1] != 'v1' or not parts[2] or \
-            not parts[3]:
-        print '<path> must point to a container at least.'
-        print 'For example: /v1/account/container'
-        print '         Or: /v1/account/container/object_prefix'
-        exit(1)
-    sig = hmac.new(key, '%s\n%s\n%s\n%s\n%s' % (path, redirect, max_file_size,
-                                                max_file_count, expires),
-                   sha1).hexdigest()
-    print '  Expires:', expires
-    print 'Signature:', sig
+if __name__ == "__main__":
+    sys.exit(swift.cli.form_signature.main(sys.argv))
diff --git a/swift/cli/form_signature.py b/swift/cli/form_signature.py
new file mode 100644
index 000000000..20452f36c
--- /dev/null
+++ b/swift/cli/form_signature.py
@@ -0,0 +1,86 @@
+# Copyright (c) 2010-2012 OpenStack Foundation
+# 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.
+
+"""
+Script for generating a form signature for use with FormPost middleware.
+"""
+import hmac
+from hashlib import sha1
+from os.path import basename
+from time import time
+
+
+def main(argv):
+    if len(argv) != 7:
+        prog = basename(argv[0])
+        print 'Syntax: %s <path> <redirect> <max_file_size> ' \
+              '<max_file_count> <seconds> <key>' % prog
+        print
+        print 'Where:'
+        print '  <path>            The prefix to use for form uploaded'
+        print '                    objects. For example:'
+        print '                    /v1/account/container/object_prefix_ would'
+        print '                    ensure all form uploads have that path'
+        print '                    prepended to the browser-given file name.'
+        print '  <redirect>        The URL to redirect the browser to after'
+        print '                    the uploads have completed.'
+        print '  <max_file_size>   The maximum file size per file uploaded.'
+        print '  <max_file_count>  The maximum number of uploaded files'
+        print '                    allowed.'
+        print '  <seconds>         The number of seconds from now to allow'
+        print '                    the form post to begin.'
+        print '  <key>             The X-Account-Meta-Temp-URL-Key for the'
+        print '                    account.'
+        print
+        print 'Example output:'
+        print '    Expires: 1323842228'
+        print '  Signature: 18de97e47345a82c4dbfb3b06a640dbb'
+        return 1
+    path, redirect, max_file_size, max_file_count, seconds, key = argv[1:]
+    try:
+        max_file_size = int(max_file_size)
+    except ValueError:
+        max_file_size = -1
+    if max_file_size < 0:
+        print 'Please use a <max_file_size> value greater than or equal to 0.'
+        return 1
+    try:
+        max_file_count = int(max_file_count)
+    except ValueError:
+        max_file_count = 0
+    if max_file_count < 1:
+        print 'Please use a positive <max_file_count> value.'
+        return 1
+    try:
+        expires = int(time() + int(seconds))
+    except ValueError:
+        expires = 0
+    if expires < 1:
+        print 'Please use a positive <seconds> value.'
+        return 1
+    parts = path.split('/', 4)
+    # Must be four parts, ['', 'v1', 'a', 'c'], must be a v1 request, have
+    # account and container values, and optionally have an object prefix.
+    if len(parts) < 4 or parts[0] or parts[1] != 'v1' or not parts[2] or \
+            not parts[3]:
+        print '<path> must point to a container at least.'
+        print 'For example: /v1/account/container'
+        print '         Or: /v1/account/container/object_prefix'
+        return 1
+    sig = hmac.new(key, '%s\n%s\n%s\n%s\n%s' % (path, redirect, max_file_size,
+                                                max_file_count, expires),
+                   sha1).hexdigest()
+    print '  Expires:', expires
+    print 'Signature:', sig
+    return 0
diff --git a/test/unit/cli/test_form_signature.py b/test/unit/cli/test_form_signature.py
new file mode 100644
index 000000000..fa2c9da90
--- /dev/null
+++ b/test/unit/cli/test_form_signature.py
@@ -0,0 +1,70 @@
+# -*- coding: utf-8 -*-
+# Copyright (c) 2014 Samuel Merritt <sam@swiftstack.com>
+#
+# 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 hashlib
+import hmac
+import mock
+import unittest
+from StringIO import StringIO
+
+from swift.cli import form_signature
+
+
+class TestFormSignature(unittest.TestCase):
+    def test_prints_signature(self):
+        the_time = 1406143563.020043
+        key = 'secret squirrel'
+        expires = 3600
+        path = '/v1/a/c/o'
+        redirect = 'https://example.com/done.html'
+        max_file_size = str(int(1024 * 1024 * 1024 * 3.14159))  # π GiB
+        max_file_count = '3'
+
+        expected_signature = hmac.new(
+            key,
+            "\n".join((
+                path, redirect, max_file_size, max_file_count,
+                str(int(the_time + expires)))),
+            hashlib.sha1).hexdigest()
+
+        out = StringIO()
+        with mock.patch('swift.cli.form_signature.time', lambda: the_time):
+            with mock.patch('sys.stdout', out):
+                exitcode = form_signature.main([
+                    '/path/to/swift-form-signature',
+                    path, redirect, max_file_size,
+                    max_file_count, str(expires), key])
+
+        self.assertEqual(exitcode, 0)
+        self.assertTrue("Signature: %s" % expected_signature
+                        in out.getvalue())
+        self.assertTrue("Expires: %d" % (the_time + expires,)
+                        in out.getvalue())
+
+    def test_too_few_args(self):
+        out = StringIO()
+        with mock.patch('sys.stdout', out):
+            exitcode = form_signature.main([
+                '/path/to/swift-form-signature',
+                '/v1/a/c/o', '', '12', '34', '3600'])
+
+        self.assertNotEqual(exitcode, 0)
+        usage = 'Syntax: swift-form-signature <path>'
+        self.assertTrue(usage in out.getvalue())
+
+
+if __name__ == '__main__':
+    unittest.main()