[POC] Allow more flexible factories via FactoryContext

.claude/skills/xds-dev/SKILL.md

@@ -0,0 +1,16 @@
+---
+name: xds-dev
+description: Build and test all xDS-related modules. Useful during xDS development to verify changes compile and pass tests across the full xDS module set.
+---
+
+# xDS Development
+
+Build and test commands for all xDS-related modules.
+
+## Commands
+
+### Test all xDS modules
+
+```
+./gradlew --parallel -Pretry=true :xds:test :xds-api:test :xds-validator:test :it:xds-client:test :it:xds-controlplane-api:test :it:xds-no-validation:test :it:xds-istio:test
+```

it/xds-client/src/test/java/com/linecorp/armeria/xds/client/endpoint/HttpProtocolOptionsTest.java

@@ -0,0 +1,129 @@
+/*
+ * Copyright 2026 LY Corporation
+ *
+ * LY Corporation licenses this file to you 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 com.linecorp.armeria.xds.client.endpoint;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.extension.RegisterExtension;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import com.linecorp.armeria.client.BlockingWebClient;
+import com.linecorp.armeria.client.WebClient;
+import com.linecorp.armeria.common.HttpResponse;
+import com.linecorp.armeria.common.SessionProtocol;
+import com.linecorp.armeria.server.ServerBuilder;
+import com.linecorp.armeria.testing.junit5.server.ServerExtension;
+import com.linecorp.armeria.xds.XdsBootstrap;
+import com.linecorp.armeria.xds.it.XdsResourceReader;
+
+import io.envoyproxy.envoy.config.bootstrap.v3.Bootstrap;
+
+class HttpProtocolOptionsTest {
+
+    @RegisterExtension
+    static ServerExtension server = new ServerExtension() {
+        @Override
+        protected void configure(ServerBuilder sb) {
+            sb.http(0);
+            sb.service("/", (ctx, req) -> HttpResponse.of("OK"));
+        }
+    };
+
+    // language=YAML
+    private static final String BOOTSTRAP_TEMPLATE =
+            """
+            static_resources:
+              listeners:
+              - name: my-listener
+                api_listener:
+                  api_listener:
+                    "@type": type.googleapis.com/envoy.extensions.filters.network.\
+            http_connection_manager.v3.HttpConnectionManager
+                    stat_prefix: http
+                    route_config:
+                      name: local_route
+                      virtual_hosts:
+                      - name: local_service
+                        domains: [ "*" ]
+                        routes:
+                          - match:
+                              prefix: /
+                            route:
+                              cluster: my-cluster
+                    http_filters:
+                    - name: envoy.filters.http.router
+                      typed_config:
+                        "@type": type.googleapis.com/envoy.extensions.filters.\
+            http.router.v3.Router
+              clusters:
+              - name: my-cluster
+                type: STATIC
+                load_assignment:
+                  cluster_name: my-cluster
+                  endpoints:
+                  - lb_endpoints:
+                    - endpoint:
+                        address:
+                          socket_address:
+                            address: 127.0.0.1
+                            port_value: %d
+                typed_extension_protocol_options:
+                  envoy.extensions.upstreams.http.v3.HttpProtocolOptions:
+                    "@type": type.googleapis.com/envoy.extensions.upstreams.\
+            http.v3.HttpProtocolOptions
+                    %s
+            """;
+
+    static Stream<Arguments> sessionProtocolSelection() {
+        return Stream.of(
+                Arguments.of("explicit_http_config:\n  http2_protocol_options: {}",
+                             SessionProtocol.H2C),
+                Arguments.of("explicit_http_config:\n  http_protocol_options: {}",
+                             SessionProtocol.H1C),
+                Arguments.of("auto_config: {}", SessionProtocol.HTTP)
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource
+    void sessionProtocolSelection(String protocolConfig,
+                                  SessionProtocol expectedProtocol) {
+        final String yaml = BOOTSTRAP_TEMPLATE.formatted(
+                server.httpPort(), protocolConfig.indent(20).strip());
+        final Bootstrap bootstrap = XdsResourceReader.fromYaml(yaml, Bootstrap.class);
+        final AtomicReference<SessionProtocol> protocolRef = new AtomicReference<>();
+        try (XdsBootstrap xdsBootstrap = XdsBootstrap.of(bootstrap);
+             XdsHttpPreprocessor preprocessor =
+                     XdsHttpPreprocessor.ofListener("my-listener", xdsBootstrap)) {
+            final BlockingWebClient client =
+                    WebClient.builder(preprocessor)
+                             .decorator((delegate, ctx, req) -> {
+                                 protocolRef.set(ctx.sessionProtocol());
+                                 return delegate.execute(ctx, req);
+                             })
+                             .build()
+                             .blocking();
+            client.get("/");
+            assertThat(protocolRef.get()).isEqualTo(expectedProtocol);
+        }
+    }
+}