Add new service builder codegen

codegen-server/src/main/kotlin/software/amazon/smithy/rust/codegen/server/smithy/generators/ServerOperationGenerator.kt

@@ -0,0 +1,76 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.server.smithy.generators
+
+import software.amazon.smithy.model.shapes.OperationShape
+import software.amazon.smithy.rust.codegen.rustlang.RustWriter
+import software.amazon.smithy.rust.codegen.rustlang.Writable
+import software.amazon.smithy.rust.codegen.rustlang.asType
+import software.amazon.smithy.rust.codegen.rustlang.documentShape
+import software.amazon.smithy.rust.codegen.rustlang.rust
+import software.amazon.smithy.rust.codegen.rustlang.rustTemplate
+import software.amazon.smithy.rust.codegen.rustlang.writable
+import software.amazon.smithy.rust.codegen.server.smithy.ServerCargoDependency
+import software.amazon.smithy.rust.codegen.smithy.CoreCodegenContext
+import software.amazon.smithy.rust.codegen.util.toPascalCase
+
+class ServerOperationGenerator(
+    coreCodegenContext: CoreCodegenContext,
+    private val operation: OperationShape,
+) {
+    private val runtimeConfig = coreCodegenContext.runtimeConfig
+    private val codegenScope =
+        arrayOf(
+            "SmithyHttpServer" to
+                ServerCargoDependency.SmithyHttpServer(runtimeConfig).asType(),
+        )
+    private val symbolProvider = coreCodegenContext.symbolProvider
+    private val model = coreCodegenContext.model
+
+    private val operationName = symbolProvider.toSymbol(operation).name.toPascalCase()
+    private val operationId = operation.id
+
+    /** Returns `std::convert::Infallible` if the model provides no errors. */
+    private fun operationError(): Writable = writable {
+        if (operation.errors.isEmpty()) {
+            rust("std::convert::Infallible")
+        } else {
+            rust("crate::error::${operationName}Error")
+        }
+    }
+
+    /** Returns a `Writable` containing the operation struct definition and its `OperationShape` implementation. */
+    private fun operation(): Writable = writable {
+        documentShape(operation, model)
+
+        rustTemplate(
+            """
+            pub struct $operationName;
+
+            impl #{SmithyHttpServer}::operation::OperationShape for $operationName {
+                const NAME: &'static str = "${operationId.toString().replace("#", "##")}";
+
+                type Input = crate::input::${operationName}Input;
+                type Output = crate::output::${operationName}Output;
+                type Error = #{Error:W};
+            }
+            """,
+            "Error" to operationError(),
+            *codegenScope,
+        )
+    }
+
+    fun render(writer: RustWriter) {
+        writer.rustTemplate(
+            """
+            #{Operation:W}
+            """,
+            "Operation" to operation(),
+        )
+        // Adds newline to end of render
+        writer.rust("")
+    }
+}

codegen-server/src/main/kotlin/software/amazon/smithy/rust/codegen/server/smithy/generators/ServerServiceGenerator.kt

@@ -7,8 +7,12 @@ package software.amazon.smithy.rust.codegen.server.smithy.generators
 
 import software.amazon.smithy.model.knowledge.TopDownIndex
 import software.amazon.smithy.model.shapes.OperationShape
+import software.amazon.smithy.rust.codegen.rustlang.Attribute
+import software.amazon.smithy.rust.codegen.rustlang.RustMetadata
 import software.amazon.smithy.rust.codegen.rustlang.RustModule
 import software.amazon.smithy.rust.codegen.rustlang.RustWriter
+import software.amazon.smithy.rust.codegen.rustlang.Visibility
+import software.amazon.smithy.rust.codegen.server.smithy.generators.protocol.ServerProtocol
 import software.amazon.smithy.rust.codegen.server.smithy.generators.protocol.ServerProtocolTestGenerator
 import software.amazon.smithy.rust.codegen.smithy.CoreCodegenContext
 import software.amazon.smithy.rust.codegen.smithy.RustCrate
@@ -66,6 +70,36 @@ open class ServerServiceGenerator(
         ) { writer ->
             renderOperationRegistry(writer, operations)
         }
+
+        // TODO(https://github.com/awslabs/smithy-rs/issues/1707): Remove, this is temporary.
+        rustCrate.withModule(
+            RustModule(
+                "operation_shape",
+                RustMetadata(
+                    visibility = Visibility.PUBLIC,
+                    additionalAttributes = listOf(
+                        Attribute.DocHidden,
+                    ),
+                ),
+                null,
+            ),
+        ) { writer ->
+            for (operation in operations) {
+                ServerOperationGenerator(coreCodegenContext, operation).render(writer)
+            }
+        }
+
+        // TODO(https://github.com/awslabs/smithy-rs/issues/1707): Remove, this is temporary.
+        rustCrate.withModule(
+            RustModule("service", RustMetadata(visibility = Visibility.PUBLIC, additionalAttributes = listOf(Attribute.DocHidden)), null),
+        ) { writer ->
+            val serverProtocol = ServerProtocol.fromCoreProtocol(coreCodegenContext, protocol)
+            ServerServiceGeneratorV2(
+                coreCodegenContext,
+                serverProtocol,
+            ).render(writer)
+        }
+
         renderExtras(operations)
     }