Allow extensions to contribute actions to the error page

core/runtime/src/main/java/io/quarkus/runtime/ErrorPageAction.java

@@ -0,0 +1,5 @@
+package io.quarkus.runtime;
+
+public record ErrorPageAction(String name, String url) {
+
+}

core/runtime/src/main/java/io/quarkus/runtime/TemplateHtmlBuilder.java

@@ -115,6 +115,7 @@ public class TemplateHtmlBuilder {
             + "<header>\n" +
             "    <div class=\"exception-message\">\n" +
             "        <h2 class=\"container\">%2$s</h2>\n" +
+            "        <div class=\"actions\">%3$s</div>\n" +
             "    </div>\n" +
             "</header>\n" +
             "<div class=\"container content\">\n";
@@ -176,25 +177,37 @@ public class TemplateHtmlBuilder {
     private String baseUrl;
 
     public TemplateHtmlBuilder(String title, String subTitle, String details) {
-        this(null, title, subTitle, details, null, Collections.emptyList());
+        this(null, title, subTitle, details, Collections.emptyList(), null, Collections.emptyList());
     }
 
-    public TemplateHtmlBuilder(String baseUrl, String title, String subTitle, String details) {
-        this(baseUrl, title, subTitle, details, null, Collections.emptyList());
+    public TemplateHtmlBuilder(String title, String subTitle, String details, List<ErrorPageAction> actions) {
+        this(null, title, subTitle, details, actions, null, Collections.emptyList());
     }
 
-    public TemplateHtmlBuilder(String title, String subTitle, String details, String redirect,
+    public TemplateHtmlBuilder(String baseUrl, String title, String subTitle, String details, List<ErrorPageAction> actions) {
+        this(baseUrl, title, subTitle, details, actions, null, Collections.emptyList());
+    }
+
+    public TemplateHtmlBuilder(String title, String subTitle, String details, List<ErrorPageAction> actions, String redirect,
             List<CurrentConfig> config) {
-        this(null, title, subTitle, details, null, Collections.emptyList());
+        this(null, title, subTitle, details, actions, null, Collections.emptyList());
     }
 
-    public TemplateHtmlBuilder(String baseUrl, String title, String subTitle, String details, String redirect,
+    public TemplateHtmlBuilder(String baseUrl, String title, String subTitle, String details, List<ErrorPageAction> actions,
+            String redirect,
             List<CurrentConfig> config) {
         this.baseUrl = baseUrl;
+
         loadCssFile();
+
+        StringBuilder actionLinks = new StringBuilder();
+        for (ErrorPageAction epa : actions) {
+            actionLinks.append(buildLink(epa.name(), epa.url()));
+        }
+
         result = new StringBuilder(String.format(HTML_TEMPLATE_START, escapeHtml(title),
                 subTitle == null || subTitle.isEmpty() ? "" : " - " + escapeHtml(subTitle), CSS));
-        result.append(String.format(HEADER_TEMPLATE, escapeHtml(title), escapeHtml(details)));
+        result.append(String.format(HEADER_TEMPLATE, escapeHtml(title), escapeHtml(details), actionLinks.toString()));
         if (!config.isEmpty()) {
             result.append(String.format(CONFIG_EDITOR_HEAD, redirect));
             for (CurrentConfig i : config) {
@@ -379,4 +392,8 @@ public void loadCssFile() {
             }
         }
     }
+
+    private String buildLink(String name, String url) {
+        return "<a href=" + url + ">" + name + "</a>";
+    }
 }

extensions/vertx-http/deployment/src/main/java/io/quarkus/vertx/http/deployment/ErrorPageActionsBuildItem.java

@@ -0,0 +1,29 @@
+package io.quarkus.vertx.http.deployment;
+
+import java.util.List;
+
+import io.quarkus.builder.item.MultiBuildItem;
+import io.quarkus.runtime.ErrorPageAction;
+
+/**
+ * Allows extensions to contribute an action (button) to the error page
+ */
+public final class ErrorPageActionsBuildItem extends MultiBuildItem {
+    private final List<ErrorPageAction> actions;
+
+    public ErrorPageActionsBuildItem(String name, String url) {
+        this(new ErrorPageAction(name, url));
+    }
+
+    public ErrorPageActionsBuildItem(ErrorPageAction errorPageAction) {
+        this(List.of(errorPageAction));
+    }
+
+    public ErrorPageActionsBuildItem(List<ErrorPageAction> errorPageAction) {
+        this.actions = errorPageAction;
+    }
+
+    public List<ErrorPageAction> getActions() {
+        return actions;
+    }
+}

extensions/vertx-http/deployment/src/main/java/io/quarkus/vertx/http/deployment/VertxHttpProcessor.java

@@ -51,6 +51,7 @@
 import io.quarkus.deployment.pkg.steps.NoopNativeImageBuildRunner;
 import io.quarkus.kubernetes.spi.KubernetesPortBuildItem;
 import io.quarkus.netty.runtime.virtual.VirtualServerChannel;
+import io.quarkus.runtime.ErrorPageAction;
 import io.quarkus.runtime.LaunchMode;
 import io.quarkus.runtime.LiveReloadConfig;
 import io.quarkus.runtime.RuntimeValue;
@@ -338,6 +339,7 @@ ServiceStartBuildItem finalizeRouter(
             HttpBuildTimeConfig httpBuildTimeConfig,
             List<RequireBodyHandlerBuildItem> requireBodyHandlerBuildItems,
             BodyHandlerBuildItem bodyHandlerBuildItem,
+            List<ErrorPageActionsBuildItem> errorPageActionsBuildItems,
             BuildProducer<ShutdownListenerBuildItem> shutdownListenerBuildItemBuildProducer,
             ShutdownConfig shutdownConfig,
             LiveReloadConfig lrc,
@@ -391,6 +393,12 @@ ServiceStartBuildItem finalizeRouter(
             }
         }
 
+        // Combine all error actions from exceptions
+        List<ErrorPageAction> combinedActions = new ArrayList<>();
+        for (ErrorPageActionsBuildItem errorPageActionsBuildItem : errorPageActionsBuildItems) {
+            combinedActions.addAll(errorPageActionsBuildItem.getActions());
+        }
+
         recorder.finalizeRouter(beanContainer.getValue(),
                 defaultRoute.map(DefaultRouteBuildItem::getRoute).orElse(null),
                 listOfFilters, listOfManagementInterfaceFilters,
@@ -401,7 +409,8 @@ ServiceStartBuildItem finalizeRouter(
                 nonApplicationRootPathBuildItem.getNonApplicationRootPath(),
                 launchMode.getLaunchMode(),
                 getBodyHandlerRequiredConditions(requireBodyHandlerBuildItems), bodyHandlerBuildItem.getHandler(),
-                gracefulShutdownFilter, shutdownConfig, executorBuildItem.getExecutorProxy());
+                gracefulShutdownFilter, shutdownConfig, executorBuildItem.getExecutorProxy(),
+                combinedActions);
 
         return new ServiceStartBuildItem("vertx-http");
     }

extensions/vertx-http/runtime/src/main/java/io/quarkus/vertx/http/runtime/QuarkusErrorHandler.java

@@ -18,6 +18,7 @@
 
 import io.netty.handler.codec.http.HttpHeaderNames;
 import io.netty.handler.codec.http.HttpResponseStatus;
+import io.quarkus.runtime.ErrorPageAction;
 import io.quarkus.runtime.TemplateHtmlBuilder;
 import io.quarkus.security.AuthenticationException;
 import io.quarkus.security.ForbiddenException;
@@ -43,12 +44,20 @@ public class QuarkusErrorHandler implements Handler<RoutingContext> {
     private final boolean showStack;
     private final boolean decorateStack;
     private final Optional<HttpConfiguration.PayloadHint> contentTypeDefault;
+    private final List<ErrorPageAction> actions;
 
     public QuarkusErrorHandler(boolean showStack, boolean decorateStack,
             Optional<HttpConfiguration.PayloadHint> contentTypeDefault) {
+        this(showStack, decorateStack, contentTypeDefault, List.of());
+    }
+
+    public QuarkusErrorHandler(boolean showStack, boolean decorateStack,
+            Optional<HttpConfiguration.PayloadHint> contentTypeDefault,
+            List<ErrorPageAction> actions) {
         this.showStack = showStack;
         this.decorateStack = decorateStack;
         this.contentTypeDefault = contentTypeDefault;
+        this.actions = actions;
     }
 
     @Override
@@ -200,10 +209,12 @@ private void jsonResponse(RoutingContext event, String contentType, String detai
 
     private void htmlResponse(RoutingContext event, String details, Throwable exception) {
         event.response().headers().set(HttpHeaderNames.CONTENT_TYPE, "text/html; charset=utf-8");
-        final TemplateHtmlBuilder htmlBuilder = new TemplateHtmlBuilder("Internal Server Error", details, details);
+        final TemplateHtmlBuilder htmlBuilder = new TemplateHtmlBuilder("Internal Server Error", details, details,
+                this.actions);
         if (showStack && exception != null) {
             htmlBuilder.stack(exception);
         }
+
         writeResponse(event, htmlBuilder.toString());
     }
 

extensions/vertx-http/runtime/src/main/java/io/quarkus/vertx/http/runtime/VertxHttpRecorder.java

@@ -54,6 +54,7 @@
 import io.quarkus.netty.runtime.virtual.VirtualAddress;
 import io.quarkus.netty.runtime.virtual.VirtualChannel;
 import io.quarkus.netty.runtime.virtual.VirtualServerChannel;
+import io.quarkus.runtime.ErrorPageAction;
 import io.quarkus.runtime.LaunchMode;
 import io.quarkus.runtime.LiveReloadConfig;
 import io.quarkus.runtime.QuarkusBindException;
@@ -377,7 +378,8 @@ public void finalizeRouter(BeanContainer container, Consumer<Route> defaultRoute
             LaunchMode launchMode, BooleanSupplier[] requireBodyHandlerConditions,
             Handler<RoutingContext> bodyHandler,
             GracefulShutdownFilter gracefulShutdownFilter, ShutdownConfig shutdownConfig,
-            Executor executor) {
+            Executor executor,
+            List<ErrorPageAction> actions) {
         HttpConfiguration httpConfiguration = this.httpConfiguration.getValue();
         // install the default route at the end
         Router httpRouteRouter = httpRouterRuntimeValue.getValue();
@@ -415,8 +417,7 @@ public void finalizeRouter(BeanContainer container, Consumer<Route> defaultRoute
         applyCompression(httpBuildTimeConfig.enableCompression, httpRouteRouter);
         httpRouteRouter.route().last().failureHandler(
                 new QuarkusErrorHandler(launchMode.isDevOrTest(), decorateStacktrace(launchMode, httpConfiguration),
-                        httpConfiguration.unhandledErrorContentTypeDefault));
-
+                        httpConfiguration.unhandledErrorContentTypeDefault, actions));
         for (BooleanSupplier requireBodyHandlerCondition : requireBodyHandlerConditions) {
             if (requireBodyHandlerCondition.getAsBoolean()) {
                 //if this is set then everything needs the body handler installed
@@ -535,7 +536,7 @@ public void handle(RoutingContext event) {
 
             mr.route().last().failureHandler(
                     new QuarkusErrorHandler(launchMode.isDevOrTest(), decorateStacktrace(launchMode, httpConfiguration),
-                            httpConfiguration.unhandledErrorContentTypeDefault));
+                            httpConfiguration.unhandledErrorContentTypeDefault, actions));
 
             mr.route().order(RouteConstants.ROUTE_ORDER_BODY_HANDLER_MANAGEMENT)
                     .handler(createBodyHandlerForManagementInterface());

extensions/vertx-http/runtime/src/main/java/io/quarkus/vertx/http/runtime/devmode/ReplacementDebugPage.java

@@ -64,7 +64,7 @@ public static String generateHtml(final Throwable exception, String currentUri)
         }
 
         TemplateHtmlBuilder builder = new TemplateHtmlBuilder("Error restarting Quarkus", exception.getClass().getName(),
-                generateHeaderMessage(exception), currentUri, toEdit);
+                generateHeaderMessage(exception), List.of(), currentUri, toEdit);
         builder.stack(exception);
         return builder.toString();
     }

extensions/vertx-http/runtime/src/main/java/io/quarkus/vertx/http/runtime/devmode/ResourceNotFoundData.java

@@ -75,7 +75,7 @@ public String getHTMLContent() {
 
         List<RouteDescription> combinedRoutes = getCombinedRoutes();
         TemplateHtmlBuilder builder = new TemplateHtmlBuilder(this.baseUrl,
-                HEADING, "", "Resources overview");
+                HEADING, "", "Resources overview", List.of());
 
         builder.resourcesStart(RESOURCE_ENDPOINTS);