[client] support custom classloader (#607)

Author: rbygrave

http-client/src/main/java/io/avaje/http/client/DHttpApi.java

@@ -19,11 +19,11 @@ final class DHttpApi {
   private final Map<Class<?>, HttpApiProvider<?>> providerMap = new HashMap<>();
 
   DHttpApi() {
-    init();
+    this(Thread.currentThread().getContextClassLoader());
   }
 
-  void init() {
-    for (final var apiProvider : ServiceLoader.load(GeneratedComponent.class)) {
+  DHttpApi(ClassLoader classLoader) {
+    for (final var apiProvider : ServiceLoader.load(GeneratedComponent.class, classLoader)) {
       apiProvider.register(providerMap);
     }
     log.log(DEBUG, "providers for {0}", providerMap.keySet());
@@ -46,4 +46,9 @@ <T> T provideFor(Class<T> type, HttpClient httpClient) {
   static <T> T get(Class<T> type, HttpClient httpClient) {
     return INSTANCE.provideFor(type, httpClient);
   }
+
+  static <T> T get(Class<T> clientInterface, HttpClient httpClient, ClassLoader classLoader) {
+    return new DHttpApi(classLoader).provideFor(clientInterface, httpClient);
+  }
+
 }

http-client/src/main/java/io/avaje/http/client/DHttpClientContext.java

@@ -79,6 +79,11 @@ public <T> T create(Class<T> clientInterface) {
     return DHttpApi.get(clientInterface, this);
   }
 
+  @Override
+  public <T> T create(Class<T> clientInterface, ClassLoader classLoader) {
+    return DHttpApi.get(clientInterface, this, classLoader);
+  }
+
   @Override
   public HttpClientRequest request() {
     return retryHandler == null

http-client/src/main/java/io/avaje/http/client/HttpClient.java

@@ -62,6 +62,16 @@ static Builder builder() {
    */
   <T> T create(Class<T> clientInterface);
 
+  /**
+   * Return the http client API implementation using the given ClassLoader.
+   *
+   * @param clientInterface A <code>@Client</code> interface with annotated API methods.
+   * @param classLoader     The ClassLoader to use to service load the implementation
+   * @param <T>             The service type.
+   * @return The http client API implementation.
+   */
+  <T> T create(Class<T> clientInterface, ClassLoader classLoader);
+
   /**
    * Create a new request.
    */

http-client/src/test/java/io/avaje/http/client/DHttpApiTest.java

@@ -18,14 +18,14 @@ class DHttpApiTest {
   @Test
   void test_github_listRepos() {
 
-    final var clientContext = HttpClient.builder()
+    final var client = HttpClient.builder()
       .baseUrl("https://api.github.com")
       .bodyAdapter(new JacksonBodyAdapter())
       .build();
 
     DHttpApi httpApi = new DHttpApi();
     httpApi.addProvider(Simple.class, Simple$HttpClient::new);
-    final Simple simple = httpApi.provideFor(Simple.class, clientContext);
+    final Simple simple = httpApi.provideFor(Simple.class, client);
 
     final List<Repo> repos = simple.listRepos("rbygrave", "junk");
     assertThat(repos).isNotEmpty();
@@ -44,7 +44,7 @@ void jsonb_github_listRepos() {
       .bodyAdapter(new JsonbBodyAdapter(jsonb))
       .build();
 
-    DHttpApi httpApi = new DHttpApi();
+    DHttpApi httpApi = new DHttpApi(Thread.currentThread().getContextClassLoader());
     httpApi.addProvider(Simple.class, Simple$HttpClient::new);
     final Simple simple = httpApi.provideFor(Simple.class, client);