Support for conditional routing using expressions (#9094)

Adds a new `@RequestCondition` annotation which can make the route execution logic conditional.

benchmarks/src/jmh/java/io/micronaut/http/server/stack/FullHttpStackBenchmark.java

@@ -68,7 +68,6 @@ public static void main(String[] args) throws Exception {
             .measurementIterations(30)
             .mode(Mode.AverageTime)
             .timeUnit(TimeUnit.NANOSECONDS)
-            .addProfiler(AsyncProfiler.class, "libPath=/home/yawkat/bin/async-profiler-2.9-linux-x64/build/libasyncProfiler.so;output=flamegraph")
             .forks(1)
             .jvmArgsAppend("-Djmh.executor=CUSTOM", "-Djmh.executor.class=" + JmhFastThreadLocalExecutor.class.getName())
             .build();

core-processor/src/main/java/io/micronaut/expressions/parser/ast/access/ElementMethodCall.java

@@ -118,25 +118,27 @@ protected void generateBytecode(ExpressionVisitorContext ctx) {
     @Override
     protected CandidateMethod resolveUsedMethod(ExpressionVisitorContext ctx) {
         List<Type> argumentTypes = resolveArgumentTypes(ctx);
-        Type calleeType = callee.resolveType(ctx);
+        ClassElement classElement = callee.resolveClassElement(ctx);
+
+        if (isNullSafe() && classElement.isAssignable(Optional.class)) {
+            // safe navigate optional
+            classElement = classElement.getFirstTypeArgument().orElse(classElement);
+        }
+
 
         ElementQuery<MethodElement> methodQuery = buildMethodQuery();
-        List<CandidateMethod> candidateMethods =
-            ctx.visitorContext()
-                .getClassElement(calleeType.getClassName())
-                .stream()
-                .flatMap(element -> element.getEnclosedElements(methodQuery).stream())
+        List<CandidateMethod> candidateMethods = classElement.getEnclosedElements(methodQuery).stream()
                 .map(method -> toCandidateMethod(ctx, method, argumentTypes))
                 .filter(method -> method.isMatching(ctx.visitorContext()))
                 .toList();
 
         if (candidateMethods.isEmpty()) {
             throw new ExpressionCompilationException(
-                "No method [ " + name + stringifyArguments(ctx) + " ] available in class " + calleeType);
+                "No method [ " + name + stringifyArguments(ctx) + " ] available in class " + classElement.getName());
         } else if (candidateMethods.size() > 1) {
             throw new ExpressionCompilationException(
                 "Ambiguous method call. Found " + candidateMethods.size() +
-                    " matching methods: " + candidateMethods + " in class " + calleeType);
+                    " matching methods: " + candidateMethods + " in class " + classElement.getName());
         }
 
         return candidateMethods.iterator().next();

core-processor/src/main/java/io/micronaut/expressions/parser/ast/access/EnvironmentAccess.java

@@ -60,7 +60,7 @@ protected void generateBytecode(ExpressionVisitorContext ctx) {
     @Override
     protected ClassElement doResolveClassElement(ExpressionVisitorContext ctx) {
         resolveType(ctx);
-        return STRING_ELEMENT;
+        return ctx.visitorContext().getClassElement(String.class).orElse(STRING_ELEMENT);
     }
 
     @Override

core-processor/src/main/java/io/micronaut/expressions/parser/ast/conditional/TernaryExpression.java

@@ -116,7 +116,9 @@ public void generateBytecode(ExpressionVisitorContext ctx) {
 
     @Override
     protected ClassElement doResolveClassElement(ExpressionVisitorContext ctx) {
-        return ClassElement.of(doResolveType(ctx).getClassName());
+        String className = doResolveType(ctx).getClassName();
+        return ctx.visitorContext().getClassElement(className)
+            .orElse(ClassElement.of(className));
     }
 
     /**

core-processor/src/main/java/io/micronaut/expressions/parser/ast/literal/StringLiteral.java

@@ -50,7 +50,7 @@ public void generateBytecode(ExpressionVisitorContext ctx) {
 
     @Override
     protected ClassElement doResolveClassElement(ExpressionVisitorContext ctx) {
-        return STRING_ELEMENT;
+        return ctx.visitorContext().getClassElement(String.class).orElse(STRING_ELEMENT);
     }
 
     @Override

http-server-tck/src/main/java/io/micronaut/http/server/tck/tests/ExpressionTest.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2017-2023 original 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
+ *
+ * https://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 io.micronaut.http.server.tck.tests;
+
+import io.micronaut.context.annotation.Requires;
+import io.micronaut.http.HttpHeaders;
+import io.micronaut.http.HttpRequest;
+import io.micronaut.http.HttpStatus;
+import io.micronaut.http.MediaType;
+import io.micronaut.http.annotation.Controller;
+import io.micronaut.http.annotation.Get;
+import io.micronaut.http.annotation.RouteCondition;
+import io.micronaut.http.tck.AssertionUtils;
+import io.micronaut.http.tck.HttpResponseAssertion;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+
+import static io.micronaut.http.tck.TestScenario.asserts;
+
+@SuppressWarnings({
+    "java:S5960", // We're allowed assertions, as these are used in tests only
+    "checkstyle:MissingJavadocType",
+    "checkstyle:DesignForExtension"
+})
+public class ExpressionTest {
+    public static final String SPEC_NAME = "ExpressionTest";
+
+    @Test
+    void testConditionalGetRequest() throws IOException {
+        asserts(SPEC_NAME,
+            HttpRequest.GET("/expr/test"),
+            (server, request) -> AssertionUtils.assertThrows(server, request,
+                HttpResponseAssertion.builder()
+                    .status(HttpStatus.NOT_FOUND)
+                    .build()));
+
+        asserts(SPEC_NAME,
+            HttpRequest.GET("/expr/test")
+                .header(HttpHeaders.AUTHORIZATION, "foo"),
+            (server, request) -> AssertionUtils.assertDoesNotThrow(server, request,
+                HttpResponseAssertion.builder()
+                    .status(HttpStatus.OK)
+                    .body("ok")
+                    .build()));
+    }
+
+    @Controller("/expr")
+    @Requires(property = "spec.name", value = SPEC_NAME)
+    static class ExpressionController {
+        @Get(value = "/test")
+        @RouteCondition("#{request.headers.getFirst('Authorization')?.contains('foo')}")
+        String testGet() {
+            return "ok";
+        }
+    }
+}

http/src/main/java/io/micronaut/http/annotation/CustomHttpMethod.java

@@ -15,21 +15,21 @@
  */
 package io.micronaut.http.annotation;
 
+import io.micronaut.context.annotation.AliasFor;
+import io.micronaut.core.async.annotation.SingleResult;
+
 import java.lang.annotation.Documented;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Inherited;
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
-import io.micronaut.context.annotation.AliasFor;
-import io.micronaut.core.async.annotation.SingleResult;
-
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
 
 /**
  * This annotation is designed for non-standard http methods, that you
  * can provide by specifying the required {@link #method()} property.
- * 
+ *
  * @author spirit-1984
  * @since 1.3.0
  */

http/src/main/java/io/micronaut/http/annotation/Delete.java

@@ -15,8 +15,6 @@
  */
 package io.micronaut.http.annotation;
 
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
-
 import io.micronaut.context.annotation.AliasFor;
 import io.micronaut.core.async.annotation.SingleResult;
 
@@ -26,6 +24,8 @@
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
 /**
  * Annotation that can be applied to method to signify the method receives a {@link io.micronaut.http.HttpMethod#DELETE}.
  *

http/src/main/java/io/micronaut/http/annotation/Get.java

@@ -15,8 +15,6 @@
  */
 package io.micronaut.http.annotation;
 
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
-
 import io.micronaut.context.annotation.AliasFor;
 import io.micronaut.core.async.annotation.SingleResult;
 
@@ -26,6 +24,8 @@
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
 /**
  * Annotation that can be applied to method to signify the method receives a {@link io.micronaut.http.HttpMethod#GET}.
  *

http/src/main/java/io/micronaut/http/annotation/Head.java

@@ -15,8 +15,6 @@
  */
 package io.micronaut.http.annotation;
 
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
-
 import io.micronaut.context.annotation.AliasFor;
 
 import java.lang.annotation.Documented;
@@ -25,6 +23,8 @@
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
 /**
  * Annotation that can be applied to method to signify the method receives a {@link io.micronaut.http.HttpMethod#HEAD}.
  *

http/src/main/java/io/micronaut/http/annotation/Options.java

@@ -15,8 +15,6 @@
  */
 package io.micronaut.http.annotation;
 
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
-
 import io.micronaut.context.annotation.AliasFor;
 
 import java.lang.annotation.Documented;
@@ -25,6 +23,8 @@
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
 /**
  * Annotation that can be applied to method to signify the method receives a
  * {@link io.micronaut.http.HttpMethod#OPTIONS}.
@@ -67,4 +67,5 @@
      */
     @AliasFor(annotation = Consumes.class, member = "value")
     String[] consumes() default {};
+
 }

http/src/main/java/io/micronaut/http/annotation/Patch.java

@@ -15,8 +15,6 @@
  */
 package io.micronaut.http.annotation;
 
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
-
 import io.micronaut.context.annotation.AliasFor;
 import io.micronaut.core.async.annotation.SingleResult;
 
@@ -26,6 +24,8 @@
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
 /**
  * Annotation that can be applied to method to signify the method receives a {@link io.micronaut.http.HttpMethod#PATCH}.
  *

http/src/main/java/io/micronaut/http/annotation/Post.java

@@ -15,8 +15,6 @@
  */
 package io.micronaut.http.annotation;
 
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
-
 import io.micronaut.context.annotation.AliasFor;
 import io.micronaut.core.async.annotation.SingleResult;
 
@@ -26,6 +24,8 @@
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
 /**
  * Annotation that can be applied to method to signify the method receives a {@link io.micronaut.http.HttpMethod#POST}.
  *

http/src/main/java/io/micronaut/http/annotation/Put.java

@@ -15,8 +15,6 @@
  */
 package io.micronaut.http.annotation;
 
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
-
 import io.micronaut.context.annotation.AliasFor;
 import io.micronaut.core.async.annotation.SingleResult;
 
@@ -26,6 +24,8 @@
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
 /**
  * Annotation that can be applied to method to signify the method receives a {@link io.micronaut.http.HttpMethod#PUT}.
  *

http/src/main/java/io/micronaut/http/annotation/RouteCondition.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2017-2023 original 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
+ *
+ * https://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 io.micronaut.http.annotation;
+
+import io.micronaut.context.annotation.AnnotationExpressionContext;
+import io.micronaut.core.annotation.Experimental;
+import io.micronaut.http.expression.RequestConditionContext;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Allows defining a condition for this route to match using an expression.
+ *
+ * <p>Within the scope of the expression a {@code request} variable is available that references the {@link io.micronaut.http.HttpRequest}.</p>
+ *
+ * <p>When added to a method the condition will be evaluated during route matching and if the condition
+ * does not evaluate to {@code true} the route will not be matched resulting in a {@link io.micronaut.http.HttpStatus#NOT_FOUND} response.  </p>
+ *
+ * <p>Note that this annotation only applies to the server and is ignored when placed on declarative HTTP client routes.</p>
+ *
+ * @see io.micronaut.http.expression.RequestConditionContext
+ * @since 4.0.0
+ */
+@Target(ElementType.METHOD)
+@Retention(RetentionPolicy.RUNTIME)
+@AnnotationExpressionContext(RequestConditionContext.class)
+@Experimental
+public @interface RouteCondition {
+    /**
+     * An expression that evalutes to {@code true} or {@code false}.
+     * @return The expression
+     * @since 4.0.0
+     */
+    String value();
+}

http/src/main/java/io/micronaut/http/annotation/Trace.java

@@ -15,8 +15,6 @@
  */
 package io.micronaut.http.annotation;
 
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
-
 import io.micronaut.context.annotation.AliasFor;
 
 import java.lang.annotation.Documented;
@@ -25,6 +23,8 @@
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
 /**
  * Annotation that can be applied to method to signify the method receives a {@link io.micronaut.http.HttpMethod#TRACE}.
  *