Fix #217: Add User-Agent header parser

http-common/pom.xml

@@ -19,6 +19,10 @@
             <artifactId>jakarta.servlet-api</artifactId>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>org.slf4j</groupId>
+            <artifactId>slf4j-api</artifactId>
+        </dependency>
 
         <dependency>
             <groupId>org.springframework.boot</groupId>

http-common/src/main/java/com/wultra/core/http/common/headers/UserAgent.java

@@ -0,0 +1,98 @@
+/*
+ * Copyright 2023 Wultra s.r.o.
+ *
+ * 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 com.wultra.core.http.common.headers;
+
+import lombok.Data;
+import lombok.extern.slf4j.Slf4j;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * Utility class for processing our standard user agent strings.
+ *
+ * @author Petr Dvorak, [email protected]
+ */
+@Slf4j
+public final class UserAgent {
+
+    @Data
+    public static class Device {
+        private String networkVersion;
+        private String language;
+        private String connection;
+        private String product;
+        private String version;
+        private String platform;
+        private String os;
+        private String osVersion;
+        private String model;
+    }
+
+    private UserAgent() {
+    }
+
+    private static final Pattern patternPrefix = Pattern.compile("^PowerAuthNetworking/(?<networkVersion>[0-9]+\\.[0-9]+\\.[0-9]+).*");
+    private static final Pattern patternV1 = Pattern.compile("^PowerAuthNetworking/(?<networkVersion>[0-9]+\\.[0-9]+\\.[0-9]+) " +
+            "\\((?<language>[a-zA-Z]{2}); (?<connection>[a-zA-Z0-9]+)\\) " +
+            "(?<product>[a-zA-Z0-9-_.]+)/(?<version>[0-9.]+) .*" +
+            "\\((?<platform>[^;]+); (?<os>[^/]+)/(?<osVersion>[^;]+); (?<model>[^)]+)\\)$");
+
+    public static Device parse(String userAgent) {
+        // Identify if the user agent is ours and in what version
+        logger.debug("Parsing user agent value: {}", userAgent);
+        final Matcher matcherPrefix = patternPrefix.matcher(userAgent);
+        if (!matcherPrefix.matches()) {
+            return null;
+        }
+        final String networkVersion = matcherPrefix.group("networkVersion");
+        logger.debug("Declared networkVersion: {}", networkVersion);
+        if (!networkVersion.startsWith("1.")) { // simplistic matching for current v1.x clients
+            return null;
+        }
+
+        // Parse the device object
+        return parseUserAgentV1(userAgent);
+
+    }
+
+    /**
+     * Private method for parsing client user from the v1.x mobile clients. It is added for convenience
+     * when new versions with another formats will be eventually introduced.
+     *
+     * @param userAgent User-Agent Header String
+     * @return Parsed device info, or null if the user agent header cannot be parsed.
+     */
+    private static Device parseUserAgentV1(String userAgent) {
+        final Matcher matcher = patternV1.matcher(userAgent);
+        if (matcher.matches()) {
+            final Device device = new Device();
+            device.setNetworkVersion(matcher.group("networkVersion"));
+            device.setLanguage(matcher.group("language"));
+            device.setConnection(matcher.group("connection"));
+            device.setProduct(matcher.group("product"));
+            device.setVersion(matcher.group("version"));
+            device.setPlatform(matcher.group("platform"));
+            device.setOs(matcher.group("os"));
+            device.setOsVersion(matcher.group("osVersion"));
+            device.setModel(matcher.group("model"));
+            return device;
+        }
+        logger.debug("The user agent value does not match v1 client format");
+        return null;
+    }
+
+}

http-common/src/test/java/com/wultra/core/http/common/headers/UserAgentTest.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2023 Wultra s.r.o.
+ *
+ * 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 com.wultra.core.http.common.headers;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+/**
+ * Test for the user agent parser.
+ *
+ * @author Petr Dvorak, [email protected]
+ */
+class UserAgentTest {
+
+    @Test
+    void parse() {
+        final String sample = "PowerAuthNetworking/1.1.7 (en; cellular) com.wultra.app.Mobile-Token.wultra_test/2.0.0 (Apple; iOS/16.6.1; iphone12,3)";
+        final UserAgent.Device device = UserAgent.parse(sample);
+        assertNotNull(device);
+        assertEquals("1.1.7", device.getNetworkVersion());
+        assertEquals("en", device.getLanguage());
+        assertEquals("cellular", device.getConnection());
+        assertEquals("com.wultra.app.Mobile-Token.wultra_test", device.getProduct());
+        assertEquals("2.0.0", device.getVersion());
+        assertEquals("Apple", device.getPlatform());
+        assertEquals("iOS", device.getOs());
+        assertEquals("16.6.1", device.getOsVersion());
+        assertEquals("iphone12,3", device.getModel());
+    }
+}