MQTT REGEX util

+/**
+ * Copyright © 2016-2020 The Thingsboard 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 org.thingsboard.server.transport.mqtt.util;
+
+import lombok.extern.slf4j.Slf4j;
+
+import java.util.regex.Pattern;
+
+@Slf4j
+public class MqttTopicRegexUtil {
+
+    public static Pattern toRegex(String topicFilter) {
+        String regex = topicFilter
+                .replace("\\", "\\\\")
+                .replace("+", "[^/]+")
+                .replace("/#", "($|/.*)");
+        log.debug("Converting [{}] to [{}]", topicFilter, regex);
+        return Pattern.compile(regex);
+    }
+
+}

+/**
+ * Copyright © 2016-2020 The Thingsboard 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 org.thingsboard.server.transport.mqtt.util;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.runners.MockitoJUnitRunner;
+
+import javax.script.ScriptException;
+import java.util.regex.Pattern;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+@RunWith(MockitoJUnitRunner.class)
+public class MqttTopicRegexUtilTest {
+
+    private static String TEST_STR_1 = "Sensor/Temperature/House/48";
+    private static String TEST_STR_2 = "Sensor/Temperature";
+    private static String TEST_STR_3 = "Sensor/Temperature2/House/48";
+
+    @Test
+    public void metadataCanBeUpdated() throws ScriptException {
+        Pattern filter = MqttTopicRegexUtil.toRegex("Sensor/Temperature/House/+");
+        assertTrue(filter.matcher(TEST_STR_1).matches());
+        assertFalse(filter.matcher(TEST_STR_2).matches());
+
+        filter = MqttTopicRegexUtil.toRegex("Sensor/+/House/#");
+        assertTrue(filter.matcher(TEST_STR_1).matches());
+        assertFalse(filter.matcher(TEST_STR_2).matches());
+
+        filter = MqttTopicRegexUtil.toRegex("Sensor/#");
+        assertTrue(filter.matcher(TEST_STR_1).matches());
+        assertTrue(filter.matcher(TEST_STR_2).matches());
+        assertTrue(filter.matcher(TEST_STR_3).matches());
+
+        filter = MqttTopicRegexUtil.toRegex("Sensor/Temperature/#");
+        assertTrue(filter.matcher(TEST_STR_1).matches());
+        assertTrue(filter.matcher(TEST_STR_2).matches());
+        assertFalse(filter.matcher(TEST_STR_3).matches());
+    }
+
+}