Add verbose mode to boilerplate

hack/verify-boilerplate.sh -v will now print out why the file does
not match along with a diff if possible.

Note: boilerplate.py now has a unit test that is run along with
hack/verify-boilerplate.sh.

.gitignore

@@ -117,3 +117,4 @@ kubernetes.tar.gz
 !\.drone\.sec
 
 /bazel-*
+*.pyc

hack/boilerplate/boilerplate.py

@@ -17,6 +17,7 @@
 from __future__ import print_function
 
 import argparse
+import difflib
 import glob
 import json
 import mmap
@@ -25,16 +26,28 @@ import re
 import sys
 
 parser = argparse.ArgumentParser()
-parser.add_argument("filenames", help="list of files to check, all files if unspecified", nargs='*')
+parser.add_argument(
+    "filenames",
+    help="list of files to check, all files if unspecified",
+    nargs='*')
 
 rootdir = os.path.dirname(__file__) + "/../../"
 rootdir = os.path.abspath(rootdir)
-parser.add_argument("--rootdir", default=rootdir, help="root directory to examine")
+parser.add_argument(
+    "--rootdir", default=rootdir, help="root directory to examine")
 
 default_boilerplate_dir = os.path.join(rootdir, "hack/boilerplate")
-parser.add_argument("--boilerplate-dir", default=default_boilerplate_dir)
+parser.add_argument(
+    "--boilerplate-dir", default=default_boilerplate_dir)
+
+parser.add_argument(
+    "-v", "--verbose",
+    help="give verbose output regarding why a file does not pass",
+    action="store_true")
+
 args = parser.parse_args()
 
+verbose_out = sys.stderr if args.verbose else open("/dev/null", "w")
 
 def get_refs():
     refs = {}
@@ -52,7 +65,8 @@ def get_refs():
 def file_passes(filename, refs, regexs):
     try:
         f = open(filename, 'r')
-    except:
+    except Exception as exc:
+        print("Unable to open %s: %s" % (filename, exc), file=verbose_out)
         return False
 
     data = f.read()
@@ -79,6 +93,9 @@ def file_passes(filename, refs, regexs):
 
     # if our test file is smaller than the reference it surely fails!
     if len(ref) > len(data):
+        print('File %s smaller than reference (%d < %d)' %
+              (filename, len(data), len(ref)),
+              file=verbose_out)
         return False
 
     # trim our file to the same number of lines as the reference file
@@ -87,6 +104,7 @@ def file_passes(filename, refs, regexs):
     p = regexs["year"]
     for d in data:
         if p.search(d):
+            print('File %s is missing the year' % filename, file=verbose_out)
             return False
 
     # Replace all occurrences of the regex "2016|2015|2014" with "YEAR"
@@ -98,6 +116,12 @@ def file_passes(filename, refs, regexs):
 
     # if we don't match the reference at this point, fail
     if ref != data:
+        print("Header in %s does not match reference, diff:" % filename, file=verbose_out)
+        if args.verbose:
+            print(file=verbose_out)
+            for line in difflib.unified_diff(ref, data, 'reference', filename, lineterm=''):
+                print(line, file=verbose_out)
+            print(file=verbose_out)
         return False
 
     return True
@@ -105,7 +129,8 @@ def file_passes(filename, refs, regexs):
 def file_extension(filename):
     return os.path.splitext(filename)[1].split(".")[-1].lower()
 
-skipped_dirs = ['Godeps', 'third_party', '_gopath', '_output', '.git', 'cluster/env.sh', "vendor", "test/e2e/generated/bindata.go"]
+skipped_dirs = ['Godeps', 'third_party', '_gopath', '_output', '.git', 'cluster/env.sh',
+                "vendor", "test/e2e/generated/bindata.go", "hack/boilerplate/test"]
 
 def normalize_files(files):
     newfiles = []
@@ -166,5 +191,7 @@ def main():
         if not file_passes(filename, refs, regexs):
             print(filename, file=sys.stdout)
 
+    return 0
+
 if __name__ == "__main__":
   sys.exit(main())

hack/boilerplate/boilerplate_test.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+
+# Copyright 2016 The Kubernetes Authors.
+#
+# 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 boilerplate
+import unittest
+import StringIO
+import os
+import sys
+
+class TestBoilerplate(unittest.TestCase):
+  """
+  Note: run this test from the hack/boilerplate directory.
+
+  $ python -m unittest boilerplate_test
+  """
+
+  def test_boilerplate(self):
+    os.chdir("test/")
+
+    class Args(object):
+      def __init__(self):
+        self.filenames = []
+        self.rootdir = "."
+        self.boilerplate_dir = "../"
+        self.verbose = True
+
+    # capture stdout
+    old_stdout = sys.stdout
+    sys.stdout = StringIO.StringIO()
+
+    boilerplate.args = Args()
+    ret = boilerplate.main()
+
+    output = sorted(sys.stdout.getvalue().split())
+
+    sys.stdout = old_stdout
+
+    self.assertEquals(
+        output, ['././fail.go', '././fail.py'])

hack/boilerplate/test/fail.go

@@ -0,0 +1,19 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+fail
+
+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.
+*/
+
+package main

hack/boilerplate/test/fail.py

@@ -0,0 +1,17 @@
+#!/usr/bin/env python
+
+# Copyright 2015 The Kubernetes Authors.
+#
+# failed
+#
+# 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.

hack/boilerplate/test/pass.go

@@ -0,0 +1,17 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+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.
+*/
+
+package main

hack/boilerplate/test/pass.py

@@ -0,0 +1,17 @@
+#!/usr/bin/env python
+
+# Copyright 2015 The Kubernetes Authors.
+#
+# 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.
+
+True

hack/verify-boilerplate.sh

@@ -19,10 +19,29 @@ set -o nounset
 set -o pipefail
 
 KUBE_ROOT=$(dirname "${BASH_SOURCE}")/..
-boiler="${KUBE_ROOT}/hack/boilerplate/boilerplate.py"
+
+boilerDir="${KUBE_ROOT}/hack/boilerplate"
+boiler="${boilerDir}/boilerplate.py"
 
 files_need_boilerplate=($(${boiler} "$@"))
 
+# Run boilerplate.py unit tests
+unitTestOut="$(mktemp)"
+trap cleanup EXIT
+cleanup() {
+	rm "${unitTestOut}"
+}
+
+pushd "${boilerDir}" >/dev/null
+if ! python -m unittest boilerplate_test 2>"${unitTestOut}"; then
+	echo "boilerplate_test.py failed"
+	echo
+	cat "${unitTestOut}"
+	exit 1
+fi
+popd >/dev/null
+
+# Run boilerplate check
 if [[ ${#files_need_boilerplate[@]} -gt 0 ]]; then
   for file in "${files_need_boilerplate[@]}"; do
     echo "Boilerplate header is wrong for: ${file}"