#841 added StatusWrapper interface

handler/src/main/java/com/networknt/handler/LightHttpHandler.java

@@ -19,7 +19,9 @@
 import com.networknt.config.Config;
 import com.networknt.handler.config.HandlerConfig;
 import com.networknt.httpstring.AttachmentConstants;
+import com.networknt.service.SingletonServiceFactory;
 import com.networknt.status.Status;
+import com.networknt.status.StatusWrapper;
 import com.networknt.utility.Constants;
 
 import io.undertow.server.HttpHandler;
@@ -76,6 +78,15 @@ default void setExchangeStatus(HttpServerExchange exchange, String code, final O
      * @param status error status
      */
     default void setExchangeStatus(HttpServerExchange exchange, Status status) {
+        // Wrap default status into custom status if the implementation of StatusWrapper was provided
+        StatusWrapper statusWrapper;
+        try {
+            statusWrapper = SingletonServiceFactory.getBean(StatusWrapper.class);
+        } catch (NoClassDefFoundError e) {
+            statusWrapper = null;
+        }
+        status = statusWrapper == null ? status : statusWrapper.wrap(status, exchange);
+
         exchange.setStatusCode(status.getStatusCode());
         exchange.getResponseHeaders().put(Headers.CONTENT_TYPE, "application/json");
         status.setDescription(status.getDescription().replaceAll("\\\\", "\\\\\\\\"));

status/pom.xml

@@ -69,6 +69,10 @@
             <artifactId>junit</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>io.undertow</groupId>
+            <artifactId>undertow-core</artifactId>
+        </dependency>
     </dependencies>
 
 </project>

status/src/main/java/com/networknt/status/StatusWrapper.java

@@ -0,0 +1,24 @@
+package com.networknt.status;
+
+import io.undertow.server.HttpServerExchange;
+
+/**
+ * Interface to allow custom Status and then inject the customized status into framework through SingletonFactory
+ * <p>
+ * Implement the interface and configure in service.yml
+ * - com.networknt.status.StatusWrapper
+ *  - custom implementation
+ *
+ * @author Jiachen Sun
+ */
+
+public interface StatusWrapper {
+    /**
+     * Encapsulate the default status of the framework as a custom status
+     *
+     * @param status   The status to be wrapped
+     * @param exchange The source of custom info used to wrap status
+     * @return the custom status
+     */
+    Status wrap(Status status, HttpServerExchange exchange);
+}

status/src/test/java/com/networknt/status/StatusWrapperTest.java

@@ -0,0 +1,66 @@
+package com.networknt.status;
+
+import com.networknt.config.Config;
+import com.networknt.service.SingletonServiceFactory;
+import org.junit.AfterClass;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import java.io.File;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+@RunWith(SeparateClassloaderTestRunner.class)
+public class StatusWrapperTest {
+    private static Config config = null;
+    private static final String homeDir = System.getProperty("user.home");
+
+    @BeforeClass
+    public static void setUp() throws Exception {
+        config = Config.getInstance();
+
+        // write a config file into the user home directory.
+        List<String> implementationList = new ArrayList<>();
+        implementationList.add("com.networknt.status.TestStatusWrapper");
+        Map<String, List<String>> implementationMap = new HashMap<>();
+        implementationMap.put("com.networknt.status.StatusWrapper", implementationList);
+        List<Map<String, List<String>>> interfaceList = new ArrayList<>();
+        interfaceList.add(implementationMap);
+        Map<String, Object> singletons = new HashMap<>();
+        singletons.put("singletons", interfaceList);
+        config.getMapper().writeValue(new File(homeDir + "/service.json"), singletons);
+
+        // Add home directory to the classpath of the system class loader.
+        AppURLClassLoader classLoader = new AppURLClassLoader(new URL[0], ClassLoader.getSystemClassLoader());
+        classLoader.addURL(new File(homeDir).toURI().toURL());
+        config.setClassLoader(classLoader);
+    }
+
+    @AfterClass
+    public static void tearDown() {
+        // Remove the service.yml from home directory
+        File test = new File(homeDir + "/service.json");
+        test.delete();
+    }
+
+    @Test
+    public void testStatusWrap() {
+        StatusWrapper statusWrapper = SingletonServiceFactory.getBean(StatusWrapper.class);
+        Status status = new Status("ERR10001");
+        status = statusWrapper.wrap(status, null);
+        Assert.assertEquals("{\"error\":{\"statusCode\":401,\"code\":\"ERR10001\",\"message\":\"AUTH_TOKEN_EXPIRED\",\"description\":\"Jwt token in authorization header expired\",\"customInfo\":\"custom_info\",\"severity\":\"ERROR\"}}", status.toString());
+    }
+
+    @Test
+    public void testStatusWrapWithArgs() {
+        StatusWrapper statusWrapper = SingletonServiceFactory.getBean(StatusWrapper.class);
+        Status status = new Status("ERR11000","arg1", "arg2");
+        status = statusWrapper.wrap(status, null);
+        Assert.assertEquals("{\"error\":{\"statusCode\":400,\"code\":\"ERR11000\",\"message\":\"VALIDATOR_REQUEST_PARAMETER_QUERY_MISSING\",\"description\":\"Query parameter arg1 is required on path arg2 but not found in request.\",\"customInfo\":\"custom_info\",\"severity\":\"ERROR\"}}", status.toString());
+    }
+}

status/src/test/java/com/networknt/status/TestStatusWrapper.java

@@ -0,0 +1,42 @@
+package com.networknt.status;
+
+import io.undertow.server.HttpServerExchange;
+
+public class TestStatusWrapper implements StatusWrapper {
+    @Override
+    public Status wrap(Status status, HttpServerExchange exchange) {
+        return new TestStatus(status, exchange);
+    }
+
+    private class TestStatus extends Status {
+        private String customInfo;
+
+        public TestStatus(Status status, HttpServerExchange exchange) {
+            this.setStatusCode(status.getStatusCode());
+            this.setCode(status.getCode());
+            this.setDescription(status.getDescription());
+            this.setMessage(status.getMessage());
+            this.setSeverity(status.getSeverity());
+            this.setCustomInfo("custom_info");
+        }
+
+        public String getCustomInfo() {
+            return customInfo;
+        }
+
+        public void setCustomInfo(String customInfo) {
+            this.customInfo = customInfo;
+        }
+
+        @Override
+        public String toString() {
+            String message = "{\"error\":" + "{\"statusCode\":" + getStatusCode()
+                    + ",\"code\":\"" + getCode()
+                    + "\",\"message\":\"" + getMessage()
+                    + "\",\"description\":\"" + getDescription()
+                    + "\",\"customInfo\":\"" + getCustomInfo()
+                    + "\",\"severity\":\"" + getSeverity() + "\"}" + "}";
+            return message;
+        }
+    }
+}