Make mock matcher take a record

This record makes matching more extensible, and also no provides the
ApiOperation being invoked, allowing for more operation-specific
mocking.

Author: mtdowling

client-core/src/test/java/software/amazon/smithy/java/client/core/plugins/InjectIdempotencyTokenPluginTest.java

@@ -81,7 +81,7 @@ public void injectsToken() {
     private String callAndGetToken(String operation, Document input) {
         var mock = MockPlugin.builder()
             .addMatcher(
-                (ctx, i) -> new MockedResult.Response(
+                request -> new MockedResult.Response(
                     HttpResponse.builder()
                         .statusCode(200)
                         .headers(HttpHeaders.of(Map.of("content-type", List.of("application/json"))))

mock-client-plugin/src/main/java/software/amazon/smithy/java/client/http/mock/MatcherRequest.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.java.client.http.mock;
+
+import software.amazon.smithy.java.context.Context;
+import software.amazon.smithy.java.core.schema.ApiOperation;
+import software.amazon.smithy.java.core.schema.SerializableStruct;
+
+/**
+ * The input to a {@link MockPlugin.Builder#addMatcher} function.
+ *
+ * @param context Context of the call.
+ * @param operation Operation being called.
+ * @param input Input of the call.
+ */
+public record MatcherRequest(Context context, ApiOperation<?, ?> operation, SerializableStruct input) {}

mock-client-plugin/src/main/java/software/amazon/smithy/java/client/http/mock/MockPlugin.java

@@ -13,7 +13,6 @@
 import java.util.NoSuchElementException;
 import java.util.ServiceLoader;
 import java.util.concurrent.CompletableFuture;
-import java.util.function.BiFunction;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 import software.amazon.smithy.java.client.core.ClientConfig;
@@ -64,7 +63,7 @@ public final class MockPlugin implements ClientPlugin {
         .map(ServiceLoader.Provider::get)
         .collect(Collectors.toMap(ServerProtocolProvider::getProtocolId, Function.identity()));
 
-    private final List<BiFunction<Context, SerializableStruct, MockedResult>> matchers = new ArrayList<>();
+    private final List<Function<MatcherRequest, MockedResult>> matchers = new ArrayList<>();
     private final List<MockedRequest> requests = Collections.synchronizedList(new ArrayList<>());
     private final Service mockService;
 
@@ -109,7 +108,7 @@ public void clearRequests() {
      * Creates a MockPlugin.
      */
     public static final class Builder {
-        private final List<BiFunction<Context, SerializableStruct, MockedResult>> matchers = new ArrayList<>();
+        private final List<Function<MatcherRequest, MockedResult>> matchers = new ArrayList<>();
 
         private Builder() {}
 
@@ -128,10 +127,10 @@ public MockPlugin build() {
          * <p>If null is returned, then subsequent matchers will attempt to match and intercept the request. If no
          * matcher intercepts the request, {@link NoSuchElementException} is thrown.
          *
-         * @param matcher Matcher that receives the context and input shape, and returns a result or null.
+         * @param matcher Matcher that returns a result or null based on the request.
          * @return the builder.
          */
-        public Builder addMatcher(BiFunction<Context, SerializableStruct, MockedResult> matcher) {
+        public Builder addMatcher(Function<MatcherRequest, MockedResult> matcher) {
             matchers.add(matcher);
             return this;
         }
@@ -147,7 +146,7 @@ public Builder addMatcher(BiFunction<Context, SerializableStruct, MockedResult>
          * @return the builder.
          */
         public Builder addQueue(MockQueue resultQueue) {
-            matchers.add((context, input) -> resultQueue.poll());
+            matchers.add(request -> resultQueue.poll());
             return this;
         }
     }
@@ -225,8 +224,13 @@ public CompletableFuture<HttpResponse> send(Context context, HttpRequest request
             requests.add(currentRequest.request());
 
             MockedResult result = null;
+            var matcherRequest = new MatcherRequest(
+                context,
+                currentRequest.operation().getApiOperation(),
+                currentRequest.request().input()
+            );
             for (var matcher : matchers) {
-                result = matcher.apply(context, currentRequest.request().input());
+                result = matcher.apply(matcherRequest);
                 if (result != null) {
                     break;
                 }

mock-client-plugin/src/test/java/software/amazon/smithy/java/client/http/mock/MockPluginTest.java

@@ -185,16 +185,16 @@ public void returnsResultsBasedOnPredicates() throws URISyntaxException {
         var bQueue = new MockQueue();
 
         var mock = MockPlugin.builder()
-            .addMatcher((ctx, i) -> {
-                if (i instanceof Document d) {
+            .addMatcher(request -> {
+                if (request.input() instanceof Document d) {
                     if (d.getMember("id").asString().equals("a")) {
                         return aQueue.poll();
                     }
                 }
                 return null;
             })
-            .addMatcher((ctx, i) -> {
-                if (i instanceof Document d) {
+            .addMatcher(request -> {
+                if (request.input() instanceof Document d) {
                     if (d.getMember("id").asString().equals("b")) {
                         return bQueue.poll();
                     }