Add checker for signed off commits

Signed-off-by: Lukas Reschke <lukas@statuscode.ch>

.drone.yml

@@ -26,6 +26,13 @@ pipeline:
     when:
       matrix:
         TESTS: app-check-code
+  signed-off-check:
+    image: nextcloudci/php7.0:php7.0-2
+    commands:
+      - php ./build/signed-off-checker.php
+    when:
+      matrix:
+        TESTS: signed-off-check
   syntax-php5.6:
     image: nextcloudci/php5.6:php5.6-2
     commands:
@@ -153,6 +160,7 @@ pipeline:
 
 matrix:
   include:
+    - TESTS: signed-off-check
     - TESTS: integration
     - TESTS: jsunit
     - TESTS: check-autoloader

build/signed-off-checker.php

@@ -0,0 +1,120 @@
+<?php
+/**
+ * @copyright Copyright (c) 2016 Lukas Reschke <lukas@statuscode.ch>
+ *
+ * @author Lukas Reschke <lukas@statuscode.ch>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * Script to verify that all commits have been signed-off, if a commit doesn't end
+ * with a signed-off message the script is failing.
+ */
+$baseDir = __DIR__ . '/../';
+
+$pullRequestNumber = getenv('DRONE_PULL_REQUEST');
+
+if(!is_string($pullRequestNumber) || $pullRequestNumber === '') {
+	echo("The environment variable DRONE_PULL_REQUEST has no proper value.\n");
+	exit(1);
+}
+
+$ch = curl_init();
+curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+curl_setopt($ch, CURLOPT_URL, 'https://api.github.com/repos/nextcloud/server/pulls/'.$pullRequestNumber.'/commits');
+curl_setopt($ch, CURLOPT_USERAGENT, 'CI for Nextcloud (https://github.com/nextcloud/server)');
+$response = curl_exec($ch);
+curl_close($ch);
+
+shell_exec(
+	sprintf(
+		'cd %s && git fetch',
+		escapeshellarg($baseDir),
+		escapeshellarg($pullRequestNumber)
+	)
+);
+
+$decodedResponse = json_decode($response, true);
+if(!is_array($decodedResponse) || count($decodedResponse) === 0) {
+	echo("Could not decode JSON response from GitHub API.\n");
+	exit(1);
+}
+
+// Get all commits SHAs
+$commits = [];
+
+foreach($decodedResponse as $commit) {
+	if(!isset($commit['sha'])) {
+		echo("No SHA specified in $commit\n");
+		exit(1);
+	}
+	$commits[] = $commit['sha'];
+}
+
+
+if(count($commits) < 1) {
+	echo("Could not read commits.\n");
+	exit(1);
+}
+
+$notSignedCommits = [];
+foreach($commits as $commit) {
+	if($commit === '') {
+		continue;
+	}
+
+	$signOffMessage = false;
+	$commitMessageLines =
+		explode(
+			"\n",
+			shell_exec(
+				sprintf(
+					'cd %s && git rev-list --format=%%B --max-count=1 %s',
+					$baseDir,
+					$commit
+				)
+			)
+		);
+
+	foreach($commitMessageLines as $line) {
+		if(preg_match('/^Signed-off-by: .* <.*@.*>$/', $line)) {
+			echo "$commit is signed-off with \"$line\"\n";
+			$signOffMessage = true;
+			continue;
+		}
+	}
+	if($signOffMessage === true) {
+		continue;
+	}
+
+	$notSignedCommits[] = $commit;
+}
+
+if($notSignedCommits !== []) {
+	echo("\n");
+	echo("Some commits were not signed off!\n");
+	echo("Missing signatures on:\n");
+	foreach ($notSignedCommits as $commit) {
+		echo("- " . $commit . "\n");
+	}
+	echo("Build has failed\n");
+	exit(1);
+} else {
+	exit(0);
+}
+