Add default error handler for HTTP requests with status 404.

calohmn · calohmn · commit aa425dce5500 · 2022-06-14T12:12:09.000+02:00
Signed-off-by: Carsten Lohmann &lt;carsten.lohmann@bosch.io&gt;
diff --git a/adapters/http-base/src/main/java/org/eclipse/hono/adapter/http/AbstractVertxBasedHttpProtocolAdapter.java b/adapters/http-base/src/main/java/org/eclipse/hono/adapter/http/AbstractVertxBasedHttpProtocolAdapter.java
@@ -298,6 +298,7 @@ protected Router createRouter() {
             }
             ctx.next();
         });
+        HttpUtils.addDefault404ErrorHandler(router);
         return router;
     }
 
diff --git a/service-base/src/main/java/org/eclipse/hono/service/http/HttpServiceBase.java b/service-base/src/main/java/org/eclipse/hono/service/http/HttpServiceBase.java
@@ -207,6 +207,7 @@ protected Router createRouter() {
             ctx.next();
         });
         addAuthHandler(router);
+        HttpUtils.addDefault404ErrorHandler(router);
         return router;
     }
 
diff --git a/service-base/src/main/java/org/eclipse/hono/service/http/HttpUtils.java b/service-base/src/main/java/org/eclipse/hono/service/http/HttpUtils.java
@@ -30,13 +30,17 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import io.netty.handler.codec.http.HttpHeaderNames;
+import io.netty.handler.codec.http.HttpResponseStatus;
 import io.opentracing.Span;
 import io.vertx.core.buffer.Buffer;
 import io.vertx.core.http.HttpHeaders;
+import io.vertx.core.http.HttpMethod;
 import io.vertx.core.http.HttpServerRequest;
 import io.vertx.core.http.HttpServerResponse;
 import io.vertx.core.json.JsonArray;
 import io.vertx.core.json.JsonObject;
+import io.vertx.ext.web.Router;
 import io.vertx.ext.web.RoutingContext;
 
 /**
@@ -371,4 +375,27 @@ public static void logErrorIfInvalidURI(final HttpServerRequest req, final Span
             TracingHelper.logError(span, "invalid request URI", e);
         }
     }
+
+    /**
+     * Adds an error handler for {@code 404} status requests to the given router.
+     * The handler adds an error log entry in the request span and sets a response body (if it's not a HEAD request).
+     *
+     * @param router The router to add the error handler to.
+     * @throws NullPointerException if router is {@code null}.
+     */
+    public static void addDefault404ErrorHandler(final Router router) {
+        Objects.requireNonNull(router);
+        router.errorHandler(404, ctx -> {
+            ctx.response().setStatusCode(404);
+            Optional.ofNullable(HttpServerSpanHelper.serverSpan(ctx))
+                    .ifPresent(span -> TracingHelper.logError(span, HttpResponseStatus.valueOf(404).reasonPhrase()));
+            if (ctx.request().method() != HttpMethod.HEAD) {
+                ctx.response()
+                        .putHeader(HttpHeaderNames.CONTENT_TYPE, "text/html; charset=utf-8")
+                        .end("<html><body><h1>Resource not found</h1></body></html>");
+            } else {
+                ctx.response().end();
+            }
+        });
+    }
 }

Original file line number	Diff line number	Diff line change
`@@ -298,6 +298,7 @@ protected Router createRouter() {`
`298`	`298`	`}`
`299`	`299`	`ctx.next();`
`300`	`300`	`});`
	`301`	`+ HttpUtils.addDefault404ErrorHandler(router);`
`301`	`302`	`return router;`
`302`	`303`	`}`
`303`	`304`
Original file line number	Diff line number	Diff line change
`@@ -207,6 +207,7 @@ protected Router createRouter() {`
`207`	`207`	`ctx.next();`
`208`	`208`	`});`
`209`	`209`	`addAuthHandler(router);`
	`210`	`+ HttpUtils.addDefault404ErrorHandler(router);`
`210`	`211`	`return router;`
`211`	`212`	`}`
`212`	`213`