Support for multipart contentType - OpenAPI v3.0

Sources/OpenAPIKit/Content/ContentEncoding.swift

@@ -27,8 +27,6 @@ extension OpenAPI.Content {
         /// where the values are anything codable.
         public var vendorExtensions: [String: AnyCodable]
 
-        /// The singular `contentType` argument is only provided for backwards compatibility and
-        /// using the plural `contentTypes` argument should be preferred.
         public init(
             contentTypes: [OpenAPI.ContentType] = [],
             headers: OpenAPI.Header.Map? = nil,

Sources/OpenAPIKit30/Content/ContentEncoding.swift

@@ -14,7 +14,7 @@ extension OpenAPI.Content {
     public struct Encoding: Equatable, CodableVendorExtendable, Sendable {
         public typealias Style = OpenAPI.Parameter.SchemaContext.Style
 
-        public let contentType: OpenAPI.ContentType?
+        public let contentTypes: [OpenAPI.ContentType]
         public let headers: OpenAPI.Header.Map?
         public let style: Style
         public let explode: Bool
@@ -27,30 +27,74 @@ extension OpenAPI.Content {
         /// where the values are anything codable.
         public var vendorExtensions: [String: AnyCodable]
 
+        /// Get the content type if only one is specified.
+        ///
+        /// - Important: This is **soft-deprecated**. Use the `contentTypes`
+        ///     property instead.
+        public var contentType: OpenAPI.ContentType? {
+            guard contentTypes.count == 1 else { return nil }
+            return contentTypes.first
+        }
+
+        /// - Important: This is **soft-deprecated**. Use the initializer
+        ///    that takes a `contentTypes` array instead.
+        public init(
+            contentType: OpenAPI.ContentType?,
+            headers: OpenAPI.Header.Map? = nil,
+            style: Style = Self.defaultStyle,
+            allowReserved: Bool = false,
+            vendorExtensions: [String: AnyCodable] = [:]
+        ) {
+            self.contentTypes = contentType.map { [$0] } ?? []
+            self.headers = headers
+            self.style = style
+            self.explode = style.defaultExplode
+            self.allowReserved = allowReserved
+            self.vendorExtensions = vendorExtensions
+        }
+
         public init(
-            contentType: OpenAPI.ContentType? = nil,
+            contentTypes: [OpenAPI.ContentType] = [],
             headers: OpenAPI.Header.Map? = nil,
             style: Style = Self.defaultStyle,
             allowReserved: Bool = false,
             vendorExtensions: [String: AnyCodable] = [:]
         ) {
-            self.contentType = contentType
+            self.contentTypes = contentTypes
             self.headers = headers
             self.style = style
             self.explode = style.defaultExplode
             self.allowReserved = allowReserved
             self.vendorExtensions = vendorExtensions
         }
 
+        /// - Important: This is **soft-deprecated**. Use the initializer
+        ///    that takes a `contentTypes` array instead.
         public init(
-            contentType: OpenAPI.ContentType? = nil,
+            contentType: OpenAPI.ContentType?,
             headers: OpenAPI.Header.Map? = nil,
             style: Style = Self.defaultStyle,
             explode: Bool,
             allowReserved: Bool = false,
             vendorExtensions: [String: AnyCodable] = [:]
         ) {
-            self.contentType = contentType
+            self.contentTypes = contentType.map { [$0] } ?? []
+            self.headers = headers
+            self.style = style
+            self.explode = explode
+            self.allowReserved = allowReserved
+            self.vendorExtensions = vendorExtensions
+        }
+
+        public init(
+            contentTypes: [OpenAPI.ContentType] = [],
+            headers: OpenAPI.Header.Map? = nil,
+            style: Style = Self.defaultStyle,
+            explode: Bool,
+            allowReserved: Bool = false,
+            vendorExtensions: [String: AnyCodable] = [:]
+        ) {
+            self.contentTypes = contentTypes
             self.headers = headers
             self.style = style
             self.explode = explode
@@ -67,7 +111,12 @@ extension OpenAPI.Content.Encoding: Encodable {
     public func encode(to encoder: Encoder) throws {
         var container = encoder.container(keyedBy: CodingKeys.self)
 
-        try container.encodeIfPresent(contentType, forKey: .contentType)
+        if contentTypes.count > 0 {
+            let contentTypesString = contentTypes
+                .map(\.rawValue)
+                .joined(separator: ", ")
+            try container.encode(contentTypesString, forKey: .contentType)
+        }
         try container.encodeIfPresent(headers, forKey: .headers)
 
         if style != Self.defaultStyle {
@@ -90,7 +139,16 @@ extension OpenAPI.Content.Encoding: Decodable {
     public init(from decoder: Decoder) throws {
         let container = try decoder.container(keyedBy: CodingKeys.self)
 
-        contentType = try container.decodeIfPresent(OpenAPI.ContentType.self, forKey: .contentType)
+        let contentTypesString = try container.decodeIfPresent(String.self, forKey: .contentType)
+        if let contentTypesString {
+            contentTypes = contentTypesString
+                .split(separator: ",")
+                .compactMap { string in
+                    OpenAPI.ContentType.init(rawValue: string.trimmingCharacters(in: .whitespaces))
+                }
+        } else {
+            contentTypes = []
+        }
 
         headers = try container.decodeIfPresent(OpenAPI.Header.Map.self, forKey: .headers)
 

Sources/OpenAPIKitCompat/Compat30To31.swift

@@ -234,7 +234,7 @@ extension OpenAPIKit30.OpenAPI.Parameter.SchemaContext.Style: To31 {
 extension OpenAPIKit30.OpenAPI.Content.Encoding: To31 {
     fileprivate func to31() -> OpenAPIKit.OpenAPI.Content.Encoding {
         OpenAPIKit.OpenAPI.Content.Encoding(
-            contentTypes: [contentType].compactMap { $0 },
+            contentTypes: contentTypes,
             headers: headers?.mapValues(eitherRefTo31),
             style: style.to31(),
             explode: explode,

Tests/OpenAPIKit30Tests/Content/ContentTests.swift

@@ -69,7 +69,7 @@ final class ContentTests: XCTestCase {
             example: nil,
             encoding: [
                 "hello": .init(
-                    contentType: .json,
+                    contentTypes: [.json],
                     headers: [
                         "world": .init(OpenAPI.Header(schemaOrContent: .init(.header(.string))))
                     ],
@@ -358,7 +358,7 @@ extension ContentTests {
     func test_encodingAndSchema_encode() {
         let content = OpenAPI.Content(
             schema: .init(.string),
-            encoding: ["json": .init(contentType: .json)]
+            encoding: ["json": .init(contentTypes: [.json])]
         )
         let encodedContent = try! orderUnstableTestStringFromEncoding(of: content)
 
@@ -400,7 +400,7 @@ extension ContentTests {
             content,
             OpenAPI.Content(
                 schema: .init(.string),
-                encoding: ["json": .init(contentType: .json)]
+                encoding: ["json": .init(contentTypes: [.json])]
             )
         )
     }
@@ -503,18 +503,18 @@ extension ContentTests {
     func test_encodingInit() {
         let _ = OpenAPI.Content.Encoding()
 
-        let _ = OpenAPI.Content.Encoding(contentType: .json)
+        let _ = OpenAPI.Content.Encoding(contentTypes: [.json])
 
         let _ = OpenAPI.Content.Encoding(headers: ["special": .a(.external(URL(string: "hello.yml")!))])
 
         let _ = OpenAPI.Content.Encoding(allowReserved: true)
 
-        let _ = OpenAPI.Content.Encoding(contentType: .form,
+        let _ = OpenAPI.Content.Encoding(contentTypes: [.form],
                                          headers: ["special": .a(.external(URL(string: "hello.yml")!))],
                                          allowReserved: true)
-        let _ = OpenAPI.Content.Encoding(contentType: .json,
+        let _ = OpenAPI.Content.Encoding(contentTypes: [.json],
                                          style: .form)
-        let _ = OpenAPI.Content.Encoding(contentType: .json,
+        let _ = OpenAPI.Content.Encoding(contentTypes: [.json],
                                          style: .form,
                                          explode: true)
     }
@@ -545,7 +545,7 @@ extension ContentTests {
     }
 
     func test_encoding_contentType_encode() throws {
-        let encoding = OpenAPI.Content.Encoding(contentType: .csv)
+        let encoding = OpenAPI.Content.Encoding(contentTypes: [.csv])
 
         let encodedEncoding = try! orderUnstableTestStringFromEncoding(of: encoding)
 
@@ -568,7 +568,34 @@ extension ContentTests {
         """.data(using: .utf8)!
         let encoding = try! orderUnstableDecode(OpenAPI.Content.Encoding.self, from: encodingData)
 
-        XCTAssertEqual(encoding, OpenAPI.Content.Encoding(contentType: .csv))
+        XCTAssertEqual(encoding, OpenAPI.Content.Encoding(contentTypes: [.csv]))
+    }
+
+    func test_encoding_multiple_contentTypes_encode() throws {
+        let encoding = OpenAPI.Content.Encoding(contentTypes: [.csv, .json])
+
+        let encodedEncoding = try! orderUnstableTestStringFromEncoding(of: encoding)
+
+        assertJSONEquivalent(
+            encodedEncoding,
+            """
+            {
+              "contentType" : "text\\/csv, application\\/json"
+            }
+            """
+        )
+    }
+
+    func test_encoding_multiple_contentTypes_decode() throws {
+        let encodingData =
+        """
+        {
+            "contentType": "text/csv, application/json"
+        }
+        """.data(using: .utf8)!
+        let encoding = try! orderUnstableDecode(OpenAPI.Content.Encoding.self, from: encodingData)
+
+        XCTAssertEqual(encoding, OpenAPI.Content.Encoding(contentTypes: [.csv, .json]))
     }
 
     func test_encoding_headers_encode() throws {
@@ -711,7 +738,7 @@ extension ContentTests {
 
     func test_encoding_vendorExtensions_encode() throws {
         let encoding = OpenAPI.Content.Encoding(
-            contentType: .json,
+            contentTypes: [.json],
             vendorExtensions: [
                 "x-custom": "value",
                 "x-nested": .init(["key": 123])
@@ -747,6 +774,7 @@ extension ContentTests {
         """.data(using: .utf8)!
         let encoding = try orderUnstableDecode(OpenAPI.Content.Encoding.self, from: encodingData)
 
+        XCTAssertEqual(encoding.contentTypes, [.json])
         XCTAssertEqual(encoding.contentType, .json)
         XCTAssertEqual(encoding.vendorExtensions["x-custom"]?.value as? String, "value")
         XCTAssertEqual((encoding.vendorExtensions["x-nested"]?.value as? [String: Int])?["key"], 123)

Tests/OpenAPIKitCompatTests/DocumentConversionTests.swift

@@ -841,6 +841,31 @@ final class DocumentConversionTests: XCTestCase {
         try assertEqualNewToOld(newParameter2, parameter2)
     }
 
+    func test_ContentEncoding() throws {
+        let encoding1 = OpenAPIKit30.OpenAPI.Content.Encoding(
+            contentTypes: [.json, .txt], headers: ["Content-Type": .header(.init(schema: .string))],
+            style: .form, allowReserved: false)
+        let encoding2 = OpenAPIKit30.OpenAPI.Content.Encoding(contentTypes: [.json], )
+
+        let content = OpenAPIKit30.OpenAPI.Content(
+            schema: .string, encoding: ["one": encoding1, "two": encoding2])
+
+        let oldDoc = OpenAPIKit30.OpenAPI.Document(
+            info: .init(title: "test", version: "1.0.0"),
+            servers: [],
+            paths: [
+                "/root": .init(
+                    summary: "path one", description: "the first path", servers: [], parameters: [],
+                    get: .init(requestBody: .init(content: [.json: content]), responses: [:]))
+            ],
+            components: .noComponents
+        )
+
+        let newDoc = oldDoc.convert(to: .v3_2_0)
+
+        try assertEqualNewToOld(newDoc, oldDoc)
+    }
+
     // TODO: more tests
 }
 
@@ -1302,7 +1327,7 @@ fileprivate func assertEqualNewToOld(_ newExample: OpenAPIKit.OpenAPI.Example, _
 }
 
 fileprivate func assertEqualNewToOld(_ newEncoding: OpenAPIKit.OpenAPI.Content.Encoding, _ oldEncoding: OpenAPIKit30.OpenAPI.Content.Encoding) throws {
-    XCTAssertEqual(newEncoding.contentTypes.first, oldEncoding.contentType)
+    XCTAssertEqual(newEncoding.contentTypes, oldEncoding.contentTypes)
     if let newEncodingHeaders = newEncoding.headers {
         let oldEncodingHeaders = try XCTUnwrap(oldEncoding.headers)
         for ((newKey, newHeader), (oldKey, oldHeader)) in zip(newEncodingHeaders, oldEncodingHeaders) {