.pytool/Plugin: Add a plugin LicenseCheck

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2691
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2833
Add a plugin to check license conflict for new added
files in a patch. It will report out errors when meeting
files which are not contributed under BSD-2-Clause-Patent.

Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Bret Barkelew <Bret.Barkelew@microsoft.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

.pytool/Plugin/LicenseCheck/LicenseCheck.py

@@ -0,0 +1,115 @@
+# @file LicenseCheck.py
+#
+# Copyright (c) 2020, Intel Corporation. All rights reserved.<BR>
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+##
+
+import os
+import logging
+import re
+from io import StringIO
+from typing import List, Tuple
+from edk2toolext.environment.plugintypes.ci_build_plugin import ICiBuildPlugin
+from edk2toolext.environment.var_dict import VarDict
+from edk2toollib.utility_functions import RunCmd
+
+
+class LicenseCheck(ICiBuildPlugin):
+
+    """
+    A CiBuildPlugin to check the license for new added files.
+
+    Configuration options:
+    "LicenseCheck": {
+        "IgnoreFiles": []
+    },
+    """
+
+    license_format_preflix = 'SPDX-License-Identifier'
+
+    bsd2_patent = 'BSD-2-Clause-Patent'
+
+    Readdedfileformat = re.compile(r'\+\+\+ b\/(.*)')
+
+    file_extension_list = [".c", ".h", ".inf", ".dsc", ".dec", ".py", ".bat", ".sh", ".uni", ".yaml",
+                           ".fdf", ".inc", "yml", ".asm", ".asm16", ".asl", ".vfr", ".s", ".S", ".aslc",
+                           ".nasm", ".nasmb", ".idf", ".Vfr", ".H"]
+
+    def GetTestName(self, packagename: str, environment: VarDict) -> tuple:
+        """ Provide the testcase name and classname for use in reporting
+            testclassname: a descriptive string for the testcase can include whitespace
+            classname: should be patterned <packagename>.<plugin>.<optionally any unique condition>
+
+            Args:
+              packagename: string containing name of package to build
+              environment: The VarDict for the test to run in
+            Returns:
+                a tuple containing the testcase name and the classname
+                (testcasename, classname)
+        """
+        return ("Check for license for " + packagename, packagename + ".LicenseCheck")
+
+    ##
+    # External function of plugin.  This function is used to perform the task of the ci_build_plugin Plugin
+    #
+    #   - package is the edk2 path to package.  This means workspace/packagepath relative.
+    #   - edk2path object configured with workspace and packages path
+    #   - PkgConfig Object (dict) for the pkg
+    #   - EnvConfig Object
+    #   - Plugin Manager Instance
+    #   - Plugin Helper Obj Instance
+    #   - Junit Logger
+    #   - output_stream the StringIO output stream from this plugin via logging
+    def RunBuildPlugin(self, packagename, Edk2pathObj, pkgconfig, environment, PLM, PLMHelper, tc, output_stream=None):
+        return_buffer = StringIO()
+        params = "diff --unified=0 origin/master HEAD"
+        RunCmd("git", params, outstream=return_buffer)
+        p = return_buffer.getvalue().strip()
+        patch = p.split("\n")
+        return_buffer.close()
+
+        ignore_files = []
+        if "IgnoreFiles" in pkgconfig:
+            ignore_files = pkgconfig["IgnoreFiles"]
+
+        self.ok = True
+        self.startcheck = False
+        self.license = True
+        self.all_file_pass = True
+        count = len(patch)
+        line_index = 0
+        for line in patch:
+            if line.startswith('--- /dev/null'):
+                nextline = patch[line_index + 1]
+                added_file = self.Readdedfileformat.search(nextline).group(1)
+                added_file_extension = os.path.splitext(added_file)[1]
+                if added_file_extension in self.file_extension_list and packagename in added_file:
+                    if (self.IsIgnoreFile(added_file, ignore_files)):
+                        line_index = line_index + 1
+                        continue
+                    self.startcheck = True
+                    self.license = False
+            if self.startcheck and self.license_format_preflix in line:
+                if self.bsd2_patent in line:
+                    self.license = True
+            if line_index + 1 == count or patch[line_index + 1].startswith('diff --') and self.startcheck:
+                if not self.license:
+                    self.all_file_pass = False
+                    error_message = "Invalid license in: " + added_file + " Hint: Only BSD-2-Clause-Patent is accepted."
+                    logging.error(error_message)
+                self.startcheck = False
+                self.license = True
+            line_index = line_index + 1
+
+        if self.all_file_pass:
+            tc.SetSuccess()
+            return 0
+        else:
+            tc.SetFailed("License Check {0} Failed. ".format(packagename), "LICENSE_CHECK_FAILED")
+            return 1
+
+    def IsIgnoreFile(self, file: str, ignore_files: List[str]) -> bool:
+        for f in ignore_files:
+            if f in file:
+                return True
+        return False

.pytool/Plugin/LicenseCheck/LicenseCheck_plug_in.yaml

@@ -0,0 +1,11 @@
+## @file
+# CiBuildPlugin used to check license issues for new added files
+#
+# Copyright (c) 2020, Intel Corporation. All rights reserved.
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+##
+{
+  "scope": "cibuild",
+  "name": "License Check Test",
+  "module": "LicenseCheck"
+}

.pytool/Plugin/LicenseCheck/Readme.md

@@ -0,0 +1,17 @@
+# License Check Plugin
+
+This CiBuildPlugin scans all new added files in a package to make sure code
+is contributed under BSD-2-Clause-Patent.
+
+## Configuration
+
+The plugin can be configured to ignore certain files.
+
+``` yaml
+"LicenseCheck": {
+    "IgnoreFiles": []
+}
+```
+### IgnoreFiles
+
+OPTIONAL List of file to ignore.