Use ScopedValue to retrieve the Request Context (#316)

* scoped value get

* workflow

* test and autocloseble

* Update CtxHolder.java

* Revert "autocloseble"

This reverts commit 775d9c8.

* test

* Make CtxHolder final and runWith() package private in java 25

- CtxHolder can be final
- Change runWith() visibility to match (package private) in both places

---------

Co-authored-by: Rob Bygrave <robin.bygrave@gmail.com>

Author: SentryMan

.github/workflows/build.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        java_version: [21]
+        java_version: [25]
         os: [ubuntu-latest]
 
     steps:

.github/workflows/jetty.yml

@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        java_version: [21]
+        java_version: [25]
         os: [ubuntu-latest]
 
     steps:

.github/workflows/robaho.yml

@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        java_version: [21]
+        java_version: [25]
         os: [ubuntu-latest]
 
     steps:

avaje-jex/pom.xml

@@ -72,4 +72,41 @@
       <scope>test</scope>
     </dependency>
   </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>compile-java-25</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <release>25</release>
+              <compileSourceRoots>
+                <compileSourceRoot>
+                  ${project.basedir}/src/main/java25</compileSourceRoot>
+              </compileSourceRoots>
+              <multiReleaseOutput>true</multiReleaseOutput>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <configuration>
+          <archive>
+            <manifestEntries>
+              <Multi-Release>true</Multi-Release>
+            </manifestEntries>
+          </archive>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
 </project>

avaje-jex/src/main/java/io/avaje/jex/core/CtxHolder.java

@@ -0,0 +1,23 @@
+package io.avaje.jex.core;
+import java.util.Optional;
+
+import io.avaje.jex.http.Context;
+
+public final class CtxHolder {
+  private static final ThreadLocal<Context> CTX = new ThreadLocal<>();
+
+  private CtxHolder() {}
+
+  static void runWith(Context ctx, Runnable task) {
+    CTX.set(ctx);
+    try {
+      task.run();
+    } finally {
+      CTX.remove();
+    }
+  }
+
+  public static Context ctx() {
+    return Optional.ofNullable(CTX.get()).orElseThrow();
+  }
+}

avaje-jex/src/main/java/io/avaje/jex/core/RoutingHandler.java

@@ -45,13 +45,16 @@ public void handle(HttpExchange exchange) {
       try {
         final Map<String, String> params = route.pathParams(uri);
         JdkContext ctx = new JdkContext(mgr, exchange, route.matchPath(), params, route.roles());
-        try {
-          ctx.setMode(Mode.BEFORE);
-          new BaseFilterChain(filters.iterator(), route.handler(), ctx, mgr).proceed();
-          handleNoResponse(exchange);
-        } catch (Exception e) {
-          mgr.handleException(ctx, e);
-        }
+        CtxHolder.runWith(ctx,
+            () -> {
+              try {
+                ctx.setMode(Mode.BEFORE);
+                new BaseFilterChain(filters.iterator(), route.handler(), ctx, mgr).proceed();
+                handleNoResponse(exchange);
+              } catch (Exception e) {
+                mgr.handleException(ctx, e);
+              }
+            });
       } finally {
         route.dec();
         exchange.close();

avaje-jex/src/main/java/io/avaje/jex/http/Context.java

@@ -23,6 +23,7 @@
 import com.sun.net.httpserver.HttpExchange;
 
 import io.avaje.jex.core.Constants;
+import io.avaje.jex.core.CtxHolder;
 import io.avaje.jex.core.json.JsonbOutput;
 import io.avaje.jex.security.BasicAuthCredentials;
 import io.avaje.jex.security.Role;
@@ -189,6 +190,11 @@ default Context contentType(ContentType contentType) {
    */
   Map<String, String> cookieMap();
 
+  /** Retrieve the context associated with the current http request. */
+  static Context currentRequest() {
+    return CtxHolder.ctx();
+  }
+
   /** Return the underlying JDK {@link HttpExchange} object backing the context */
   HttpExchange exchange();
 

avaje-jex/src/main/java25/io/avaje/jex/core/CtxHolder.java

@@ -0,0 +1,18 @@
+package io.avaje.jex.core;
+
+import io.avaje.jex.http.Context;
+
+public final class CtxHolder {
+
+  private static final ScopedValue<Context> SV = ScopedValue.newInstance();
+
+  private CtxHolder() {}
+
+  static void runWith(Context ctx, Runnable task) {
+    ScopedValue.where(SV, ctx).run(task);
+  }
+
+  public static Context ctx() {
+    return SV.get();
+  }
+}

avaje-jex/src/test/java/io/avaje/jex/http/CtxHolderTest.java

@@ -0,0 +1,29 @@
+package io.avaje.jex.http;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.util.NoSuchElementException;
+
+import org.junit.jupiter.api.Test;
+
+import io.avaje.jex.Jex;
+import io.avaje.jex.core.TestPair;
+
+class CtxHolderTest {
+  static TestPair init() {
+    final Jex app = Jex.create().get("/", __ -> Context.currentRequest().text("dummy"));
+    return TestPair.create(app);
+  }
+
+  @Test
+  void get() {
+    var pair = init();
+    assertEquals(200, pair.request().GET().asDiscarding().statusCode());
+  }
+
+  @Test
+  void notSet() {
+    assertThrows(NoSuchElementException.class, Context::currentRequest);
+  }
+}