Calculate required response header parameters for initialize

Sources/_OpenAPIGeneratorCore/Translator/Responses/translateResponse.swift

@@ -102,20 +102,23 @@ extension TypesFileTranslator {
             asSwiftSafeName: swiftSafeName
         )
 
-        let responseStructDecl = translateStructBlueprint(
-            .init(
-                comment: nil,
-                access: config.access,
-                typeName: typeName,
-                conformances: Constants.Operation.Output.Payload.conformances,
-                properties: [
-                    headersProperty,
-                    contentProperty,
-                ]
-            )
+        let structBlueprint: StructBlueprint = .init(
+            comment: nil,
+            access: config.access,
+            typeName: typeName,
+            conformances: Constants.Operation.Output.Payload.conformances,
+            properties: [
+                headersProperty,
+                contentProperty,
+            ]
         )
 
-        return responseStructDecl
+        let responseStructDecl = _calculateRequiredHeadersForInitialize(
+            with: headers,
+            from: translateStructBlueprint(structBlueprint)
+        )
+
+        return responseStructDecl.deprecate(if: structBlueprint.isDeprecated)
     }
 
     /// Returns a list of declarations for the specified reusable response
@@ -138,4 +141,82 @@ extension TypesFileTranslator {
             response: response
         )
     }
+
+    /// Calculate the necessary parameters for initializing the response headers
+    /// and return the list of specified reusable response declarations.
+    /// - Parameters:
+    ///   - headers: the typed response headers
+    ///   - responseStructDecl:　A structure declaration before calculate.
+    /// - Returns: A structure declaration.
+    private func _calculateRequiredHeadersForInitialize(
+        with headers: [TypedResponseHeader],
+        from responseStructDecl: Declaration
+    ) -> Declaration {
+        guard case .commentable(let comment, let structDec) = responseStructDecl,
+            case .struct(let structDescription) = structDec
+        else {
+            return responseStructDecl
+        }
+
+        let newMembers: [Declaration] = structDescription
+            .members
+            .reduce(into: [Declaration]()) { partialResult, member in
+                let labelHeaders = "headers"
+
+                if case .commentable(let memberComment, let memberDecl) = member,
+                    case .function(let memberFuncDescription) = memberDecl,
+                    memberFuncDescription.signature.kind == .initializer,
+                    memberFuncDescription.signature.parameters.first(where: { $0.label == labelHeaders }) != nil
+                {
+
+                    let initParameters: [ParameterDescription] = memberFuncDescription
+                        .signature
+                        .parameters
+                        .map { parameterDesc in
+                            guard parameterDesc.label == labelHeaders else {
+                                return parameterDesc
+                            }
+                            let defaultValue: Expression? = {
+                                if headers.isEmpty {
+                                    return PropertyBlueprint.DefaultValue.emptyInit.asExpression
+                                }
+                                if headers.first(where: { !$0.isOptional }) != nil {
+                                    return nil
+                                }
+                                return PropertyBlueprint.DefaultValue.emptyInit.asExpression
+                            }()
+                            return .init(
+                                label: parameterDesc.label,
+                                name: parameterDesc.name,
+                                type: parameterDesc.type,
+                                defaultValue: defaultValue
+                            )
+                        }
+
+                    let initDescription: FunctionDescription = .init(
+                        accessModifier: memberFuncDescription.signature.accessModifier,
+                        kind: memberFuncDescription.signature.kind,
+                        parameters: initParameters,
+                        keywords: memberFuncDescription.signature.keywords,
+                        returnType: memberFuncDescription.signature.returnType,
+                        body: memberFuncDescription.body
+                    )
+
+                    partialResult.append(
+                        .commentable(memberComment, .function(initDescription))
+                    )
+                } else {
+                    partialResult.append(member)
+                }
+            }
+
+        let structDescriptionWithCalc = StructDescription(
+            accessModifier: structDescription.accessModifier,
+            name: structDescription.name,
+            conformances: structDescription.conformances,
+            members: newMembers
+        )
+
+        return .commentable(comment, .struct(structDescriptionWithCalc))
+    }
 }

Tests/OpenAPIGeneratorReferenceTests/Resources/Docs/petstore.yaml

@@ -107,6 +107,13 @@ paths:
                 application/json:
                   schema:
                     $ref: '#/components/schemas/CodeError'
+            X-Extra-Arguments2:
+              required: true
+              description: "A description here."
+              content:
+                application/json:
+                  schema:
+                    $ref: '#/components/schemas/CodeError'
           content:
             application/json:
               schema:

Tests/OpenAPIGeneratorReferenceTests/Resources/ReferenceSources/Petstore/Client.swift

@@ -174,6 +174,11 @@ public struct Client: APIProtocol {
                             in: response.headerFields,
                             name: "X-Extra-Arguments",
                             as: Components.Schemas.CodeError.self
+                        ),
+                        X_Extra_Arguments2: try converter.getRequiredHeaderFieldAsJSON(
+                            in: response.headerFields,
+                            name: "X-Extra-Arguments2",
+                            as: Components.Schemas.CodeError.self
                         )
                     )
                     try converter.validateContentTypeIfPresent(

Tests/OpenAPIGeneratorReferenceTests/Resources/ReferenceSources/Petstore/Server.swift

@@ -220,6 +220,11 @@ fileprivate extension UniversalServer where APIHandler: APIProtocol {
                         name: "X-Extra-Arguments",
                         value: value.headers.X_Extra_Arguments
                     )
+                    try converter.setHeaderFieldAsJSON(
+                        in: &response.headerFields,
+                        name: "X-Extra-Arguments2",
+                        value: value.headers.X_Extra_Arguments2
+                    )
                     try converter.validateAcceptIfPresent(
                         "application/json",
                         in: request.headerFields

Tests/OpenAPIGeneratorReferenceTests/Resources/ReferenceSources/Petstore/Types.swift

@@ -686,7 +686,7 @@ public enum Components {
             ///   - headers: Received HTTP response headers
             ///   - body: Received HTTP response body
             public init(
-                headers: Components.Responses.ErrorBadRequest.Headers,
+                headers: Components.Responses.ErrorBadRequest.Headers = .init(),
                 body: Components.Responses.ErrorBadRequest.Body
             ) {
                 self.headers = headers
@@ -985,12 +985,18 @@ public enum Operations {
             public struct Created: Sendable, Equatable, Hashable {
                 public struct Headers: Sendable, Equatable, Hashable {
                     public var X_Extra_Arguments: Components.Schemas.CodeError?
+                    public var X_Extra_Arguments2: Components.Schemas.CodeError
                     /// Creates a new `Headers`.
                     ///
                     /// - Parameters:
                     ///   - X_Extra_Arguments:
-                    public init(X_Extra_Arguments: Components.Schemas.CodeError? = nil) {
+                    ///   - X_Extra_Arguments2:
+                    public init(
+                        X_Extra_Arguments: Components.Schemas.CodeError? = nil,
+                        X_Extra_Arguments2: Components.Schemas.CodeError
+                    ) {
                         self.X_Extra_Arguments = X_Extra_Arguments
+                        self.X_Extra_Arguments2 = X_Extra_Arguments2
                     }
                 }
                 /// Received HTTP response headers

Tests/OpenAPIGeneratorReferenceTests/SnippetBasedReferenceTests.swift

@@ -519,7 +519,7 @@ final class SnippetBasedReferenceTests: XCTestCase {
         )
     }
 
-    func testComponentsResponsesResponseWithHeader() throws {
+    func testComponentsResponsesResponseWithOptionalHeader() throws {
         try self.assertResponsesTranslation(
             """
             responses:
@@ -541,6 +541,42 @@ final class SnippetBasedReferenceTests: XCTestCase {
                     public var headers: Components.Responses.BadRequest.Headers
                     @frozen public enum Body: Sendable, Equatable, Hashable {}
                     public var body: Components.Responses.BadRequest.Body?
+                    public init(
+                        headers: Components.Responses.BadRequest.Headers = .init(),
+                        body: Components.Responses.BadRequest.Body? = nil
+                    ) {
+                        self.headers = headers
+                        self.body = body
+                    }
+                }
+            }
+            """
+        )
+    }
+
+    func testComponentsResponsesResponseWithRequiredHeader() throws {
+        try self.assertResponsesTranslation(
+            """
+            responses:
+              BadRequest:
+                description: Bad request
+                headers:
+                  X-Reason:
+                    schema:
+                      type: string
+                    required: true
+            """,
+            """
+            public enum Responses {
+                public struct BadRequest: Sendable, Equatable, Hashable {
+                    public struct Headers: Sendable, Equatable, Hashable {
+                        public var X_Reason: Swift.String
+                        public init(X_Reason: Swift.String) {
+                            self.X_Reason = X_Reason }
+                    }
+                    public var headers: Components.Responses.BadRequest.Headers
+                    @frozen public enum Body: Sendable, Equatable, Hashable {}
+                    public var body: Components.Responses.BadRequest.Body?
                     public init(
                         headers: Components.Responses.BadRequest.Headers,
                         body: Components.Responses.BadRequest.Body? = nil

Tests/PetstoreConsumerTests/Test_Client.swift

@@ -170,6 +170,7 @@ final class Test_Client: XCTestCase {
                 headers: [
                     .init(name: "content-type", value: "application/json; charset=utf-8"),
                     .init(name: "x-extra-arguments", value: #"{"code":1}"#),
+                    .init(name: "x-extra-arguments2", value: #"{"code":9999}"#),
                 ],
                 encodedBody: #"""
                     {
@@ -192,6 +193,7 @@ final class Test_Client: XCTestCase {
             return
         }
         XCTAssertEqual(value.headers.X_Extra_Arguments, .init(code: 1))
+        XCTAssertEqual(value.headers.X_Extra_Arguments2, .init(code: 9999))
         switch value.body {
         case .json(let pets):
             XCTAssertEqual(pets, .init(id: 1, name: "Fluffz"))

Tests/PetstoreConsumerTests/Test_Server.swift

@@ -137,7 +137,7 @@ final class Test_Server: XCTestCase {
                 return .created(
                     .init(
                         headers: .init(
-                            X_Extra_Arguments: .init(code: 1)
+                            X_Extra_Arguments2: .init(code: 1)
                         ),
                         body: .json(
                             .init(id: 1, name: "Fluffz")
@@ -166,7 +166,7 @@ final class Test_Server: XCTestCase {
         XCTAssertEqual(
             response.headerFields,
             [
-                .init(name: "X-Extra-Arguments", value: #"{"code":1}"#),
+                .init(name: "X-Extra-Arguments2", value: #"{"code":1}"#),
                 .init(name: "content-type", value: "application/json; charset=utf-8"),
             ]
         )