Add verify_boilerplate script to CI

Signed-off-by: James Munnelly <james.munnelly@jetstack.io>

Makefile

@@ -81,6 +81,8 @@ generate_verify:
 # Hack targets
 ##############
 hack_verify:
+	@echo Running boilerplate header checker
+	$(HACK_DIR)/verify_boilerplate.py
 	@echo Running href checker
 	$(HACK_DIR)/verify-links.sh
 	@echo Running errexit checker

hack/verify_boilerplate.py

@@ -0,0 +1,209 @@
+#!/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.
+
+# Verifies that all source files contain the necessary copyright boilerplate
+# snippet.
+
+from __future__ import print_function
+
+import argparse
+import glob
+import os
+import re
+import sys
+
+
+def get_args():
+    parser = argparse.ArgumentParser()
+    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")
+
+    default_boilerplate_dir = os.path.join(rootdir, "hack/boilerplate")
+    parser.add_argument("--boilerplate-dir", default=default_boilerplate_dir)
+    return parser.parse_args()
+
+
+def get_refs():
+    refs = {}
+
+    for path in glob.glob(os.path.join(ARGS.boilerplate_dir, "boilerplate.*.txt")):
+        extension = os.path.basename(path).split(".")[1]
+
+        ref_file = open(path, 'r')
+        ref = ref_file.read().splitlines()
+        ref_file.close()
+        refs[extension] = ref
+
+    return refs
+
+
+def file_passes(filename, refs, regexs):  # pylint: disable=too-many-locals
+    try:
+        with open(filename, 'r') as fp:
+            data = fp.read()
+    except IOError:
+        return False
+
+    basename = os.path.basename(filename)
+    extension = file_extension(filename)
+    if extension != "":
+        ref = refs[extension]
+    else:
+        ref = refs[basename]
+
+    # remove build tags from the top of Go files
+    if extension == "go":
+        con = regexs["go_build_constraints"]
+        (data, found) = con.subn("", data, 1)
+
+    # remove shebang from the top of shell files
+    if extension == "sh" or extension == "py":
+        she = regexs["shebang"]
+        (data, found) = she.subn("", data, 1)
+
+    data = data.splitlines()
+
+    # if our test file is smaller than the reference it surely fails!
+    if len(ref) > len(data):
+        return False
+
+    # trim our file to the same number of lines as the reference file
+    data = data[:len(ref)]
+
+    year = regexs["year"]
+    for datum in data:
+        if year.search(datum):
+            return False
+
+    # Replace all occurrences of the regex "2017|2016|2015|2014" with "YEAR"
+    when = regexs["date"]
+    for idx, datum in enumerate(data):
+        (data[idx], found) = when.subn('YEAR', datum)
+        if found != 0:
+            break
+
+    # if we don't match the reference at this point, fail
+    if ref != data:
+        return False
+
+    return True
+
+
+def file_extension(filename):
+    return os.path.splitext(filename)[1].split(".")[-1].lower()
+
+
+SKIPPED_DIRS = [
+    'Godeps', 'third_party', '_gopath', '_output',
+    '.git', 'vendor', '__init__.py', 'node_modules'
+]
+
+# even when generated by bazel we will complain about some generated files
+# not having the headers. since they're just generated, ignore them
+IGNORE_HEADERS = [
+    '// Code generated by go-bindata.'
+]
+
+
+def has_ignored_header(pathname):
+    with open(pathname, 'r') as myfile:
+        data = myfile.read()
+        for header in IGNORE_HEADERS:
+            if data.startswith(header):
+                return True
+    return False
+
+
+def normalize_files(files):
+    newfiles = []
+    for pathname in files:
+        if any(x in pathname for x in SKIPPED_DIRS):
+            continue
+        newfiles.append(pathname)
+    for idx, pathname in enumerate(newfiles):
+        if not os.path.isabs(pathname):
+            newfiles[idx] = os.path.join(ARGS.rootdir, pathname)
+    return newfiles
+
+
+def get_files(extensions):
+    files = []
+    if ARGS.filenames:
+        files = ARGS.filenames
+    else:
+        for root, dirs, walkfiles in os.walk(ARGS.rootdir):
+            # don't visit certain dirs. This is just a performance improvement
+            # as we would prune these later in normalize_files(). But doing it
+            # cuts down the amount of filesystem walking we do and cuts down
+            # the size of the file list
+            for dpath in SKIPPED_DIRS:
+                if dpath in dirs:
+                    dirs.remove(dpath)
+
+            for name in walkfiles:
+                pathname = os.path.join(root, name)
+                files.append(pathname)
+
+    files = normalize_files(files)
+    outfiles = []
+    for pathname in files:
+        basename = os.path.basename(pathname)
+        extension = file_extension(pathname)
+        if extension in extensions or basename in extensions:
+            if not has_ignored_header(pathname):
+                outfiles.append(pathname)
+    return outfiles
+
+
+def get_regexs():
+    regexs = {}
+    # Search for "YEAR" which exists in the boilerplate, but shouldn't in the real thing
+    regexs["year"] = re.compile('YEAR')
+    # dates can be 2014, 2015, 2016 or 2017, company holder names can be anything
+    regexs["date"] = re.compile('(2014|2015|2016|2017|2018)')
+    # strip // +build \n\n build constraints
+    regexs["go_build_constraints"] = re.compile(
+        r"^(// \+build.*\n)+\n", re.MULTILINE)
+    # strip #!.* from shell/python scripts
+    regexs["shebang"] = re.compile(r"^(#!.*\n)\n*", re.MULTILINE)
+    return regexs
+
+
+def main():
+    regexs = get_regexs()
+    refs = get_refs()
+    filenames = get_files(refs.keys())
+    nonconforming_files = []
+    for filename in filenames:
+        if not file_passes(filename, refs, regexs):
+            nonconforming_files.append(filename)
+
+    if nonconforming_files:
+        print('%d files have incorrect boilerplate headers:' %
+              len(nonconforming_files))
+        for filename in sorted(nonconforming_files):
+            print(os.path.relpath(filename, ARGS.rootdir))
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    ARGS = get_args()
+    main()