generate service interface

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/service/ProtocolGenerator.java

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+/*
+ * Copyright 2024 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file 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 software.amazon.smithy.go.codegen.service;
+
+import software.amazon.smithy.go.codegen.GoWriter;
+
+public interface ProtocolGenerator {
+    /**
+     * Generate the operation routing logic for this protocol.
+     * @return The writable operation handler.
+     */
+    GoWriter.Writable generateHandler();
+}

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/service/ServiceInterface.java

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+/*
+ * Copyright 2024 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file 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 software.amazon.smithy.go.codegen.service;
+
+import static software.amazon.smithy.go.codegen.GoWriter.goTemplate;
+
+import software.amazon.smithy.codegen.core.SymbolProvider;
+import software.amazon.smithy.go.codegen.GoStdlibTypes;
+import software.amazon.smithy.go.codegen.GoWriter;
+import software.amazon.smithy.model.Model;
+import software.amazon.smithy.model.knowledge.TopDownIndex;
+import software.amazon.smithy.model.shapes.OperationShape;
+import software.amazon.smithy.model.shapes.ServiceShape;
+import software.amazon.smithy.utils.MapUtils;
+
+/**
+ * Generates the interface that describes the service API.
+ */
+public final class ServiceInterface implements GoWriter.Writable {
+    public static final String NAME = "Service";
+
+    private final Model model;
+    private final ServiceShape service;
+    private final SymbolProvider symbolProvider;
+
+    public ServiceInterface(Model model, ServiceShape service, SymbolProvider symbolProvider) {
+        this.model = model;
+        this.service = service;
+        this.symbolProvider = symbolProvider;
+    }
+
+    @Override
+    public void accept(GoWriter writer) {
+        writer.write(generateInterface());
+    }
+
+    private GoWriter.Writable generateInterface() {
+        return goTemplate("""
+                type $L interface {
+                    $W
+                }
+                """, NAME, generateOperations());
+    }
+
+    private GoWriter.Writable generateOperations() {
+        return GoWriter.ChainWritable.of(
+                TopDownIndex.of(model).getContainedOperations(service).stream()
+                        .map(this::generateOperation)
+                        .toList()
+        ).compose(false);
+    }
+
+    private GoWriter.Writable generateOperation(OperationShape operation) {
+        return goTemplate(
+                "$operation:T($context:L, $input:P) ($output:P, error)",
+                MapUtils.of(
+                        "operation", symbolProvider.toSymbol(operation),
+                        "context", GoStdlibTypes.Context.Context,
+                        "input", symbolProvider.toSymbol(model.expectShape(operation.getInputShape())),
+                        "output", symbolProvider.toSymbol(model.expectShape(operation.getOutputShape()))
+                )
+        );
+    }
+}