Add scalars and simple async resolve functions.

README.md

@@ -133,7 +133,7 @@ import NIO
 let root = MessageAPI()
 let context = MessageStore()
 let service = try MessageService(root: root)
-let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
+let group = MultiThreadedEventLoopGroup(numberOfThreads: System.coreCount)
 
 defer {
     try? group.syncShutdownGracefully()

Sources/Graphiti/ComponentsInitializer.swift

@@ -1,3 +1,6 @@
+import Foundation
+import GraphQL
+
 public final class ComponentsInitializer<RootType : Keyable, Context> {
     var components: [Component<RootType, Context>] = []
 
@@ -168,4 +171,59 @@ public final class ComponentsInitializer<RootType : Keyable, Context> {
         components.append(component)
         return ComponentInitializer(component)
     }
+
+    @discardableResult
+    public func dateScalar(
+        formatter: Formatter
+    ) -> ComponentInitializer<RootType, Context> {
+        scalar(
+            Date.self,
+            serialize: { date in
+                guard let string = formatter.string(for: date) else {
+                    throw GraphQLError(message: "Invalid value for Date scalar. Cannot convert \"\(date)\" to string.")
+                }
+
+                return .string(string)
+            },
+            parse: { map in
+                guard let string = map.string else {
+                    throw GraphQLError(message: "Invalid type for Date scalar. Expected string, but got \(map.typeDescription)")
+                }
+
+                var date = Date()
+                let datePointer = AutoreleasingUnsafeMutablePointer<AnyObject?>(&date)
+
+                guard formatter.getObjectValue(datePointer, for: string, errorDescription: nil) else {
+                    throw GraphQLError(message: "Invalid date string for Date scalar.")
+                }
+
+                guard let formattedDate = datePointer.pointee as? Date else {
+                    throw GraphQLError(message: "Invalid date string for Date scalar.")
+                }
+
+                return formattedDate
+            }
+        )
+    }
+
+    @discardableResult
+    public func urlScalar() -> ComponentInitializer<RootType, Context> {
+        scalar(
+            URL.self,
+            serialize: { url in
+                .string(url.absoluteString)
+            },
+            parse: { map in
+                guard let string = map.string else {
+                    throw GraphQLError(message: "Invalid type for URL scalar.")
+                }
+
+                guard let url = URL(string: string) else {
+                    throw GraphQLError(message: "Invalid url string for URL scalar.")
+                }
+
+                return url
+            }
+        )
+    }
 }

Sources/Graphiti/FieldsInitializer.swift

@@ -1,3 +1,5 @@
+import NIO
+
 public final class FieldsInitializer<ObjectType, Keys : RawRepresentable, Context> where Keys.RawValue == String {
     var fields: [FieldComponent<ObjectType, Keys, Context>] = []
 
@@ -96,4 +98,37 @@ public final class FieldsInitializer<ObjectType, Keys : RawRepresentable, Contex
         fields.append(field)
         return FieldInitializer(field)
     }
+
+    @discardableResult
+    public func field<FieldType, ResolveType>(
+        _ name: Keys,
+        at function: @escaping SimpleAsyncResolve<ObjectType, Context, NoArguments, ResolveType>,
+        overridingType: FieldType.Type = FieldType.self
+    ) -> FieldInitializer<ObjectType, Keys, Context, NoArguments> {
+        let asyncResolve: AsyncResolve<ObjectType, Context, NoArguments, ResolveType> = { type in
+            return { context, arguments, group in
+                // We hop to guarantee that the future will
+                // return in the same event loop group of the execution.
+                try function(type)(context, arguments).hop(to: group.next())
+            }
+        }
+
+        return field(name, at: asyncResolve, overridingType: overridingType)
+    }
+
+    @discardableResult
+    public func field<Arguments : Decodable, ResolveType>(
+        _ name: Keys,
+        at function: @escaping SimpleAsyncResolve<ObjectType, Context, Arguments, ResolveType>
+    ) -> FieldInitializer<ObjectType, Keys, Context, Arguments> {
+        let asyncResolve: AsyncResolve<ObjectType, Context, Arguments, ResolveType> = { type in
+            return { context, arguments, group in
+                // We hop to guarantee that the future will
+                // return in the same event loop group of the execution.
+                try function(type)(context, arguments).hop(to: group.next())
+            }
+        }
+
+        return field(name, at: asyncResolve)
+    }
 }

Sources/Graphiti/SimpleAsyncResolve.swift

@@ -0,0 +1,8 @@
+import NIO
+
+public typealias SimpleAsyncResolve<ObjectType, Context, Arguments, ResolveType> = (
+    _ object: ObjectType
+)  -> (
+    _ context: Context,
+    _ arguments: Arguments
+) throws -> EventLoopFuture<ResolveType>

Tests/GraphitiTests/HelloWorldTests/HelloWorldTests.swift

@@ -146,7 +146,7 @@ struct HelloService : Service {
 
 class HelloWorldTests : XCTestCase {
     private let service = HelloService()
-    private var group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
+    private var group = MultiThreadedEventLoopGroup(numberOfThreads: System.coreCount)
 
     deinit {
         try? self.group.syncShutdownGracefully()

Tests/GraphitiTests/StarWarsTests/StarWarsIntrospectionTests.swift

@@ -6,14 +6,13 @@ import GraphQL
 
 class StarWarsIntrospectionTests : XCTestCase {
     private let service = StarWarsService()
+    private let group = MultiThreadedEventLoopGroup(numberOfThreads: System.coreCount)
+
+    deinit {
+        try? group.syncShutdownGracefully()
+    }
 
     func testIntrospectionTypeQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionTypeQuery {" +
                     "    __schema {" +
                     "        types {" +
@@ -95,12 +94,6 @@ class StarWarsIntrospectionTests : XCTestCase {
     }
 
     func testIntrospectionQueryTypeQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionQueryTypeQuery {" +
                     "    __schema {" +
                     "        queryType {" +
@@ -129,12 +122,6 @@ class StarWarsIntrospectionTests : XCTestCase {
     }
 
     func testIntrospectionDroidTypeQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionDroidTypeQuery {" +
                     "    __type(name: \"Droid\") {" +
                     "        name" +
@@ -159,12 +146,6 @@ class StarWarsIntrospectionTests : XCTestCase {
     }
 
     func testIntrospectionDroidKindQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionDroidKindQuery {" +
                     "    __type(name: \"Droid\") {" +
                     "        name" +
@@ -191,12 +172,6 @@ class StarWarsIntrospectionTests : XCTestCase {
     }
 
     func testIntrospectionCharacterKindQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionCharacterKindQuery {" +
                     "    __type(name: \"Character\") {" +
                     "        name" +
@@ -223,12 +198,6 @@ class StarWarsIntrospectionTests : XCTestCase {
     }
 
     func testIntrospectionDroidFieldsQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionDroidFieldsQuery {" +
                     "    __type(name: \"Droid\") {" +
                     "        name" +
@@ -304,12 +273,6 @@ class StarWarsIntrospectionTests : XCTestCase {
     }
 
     func testIntrospectionDroidNestedFieldsQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionDroidNestedFieldsQuery {" +
                     "    __type(name: \"Droid\") {" +
                     "        name" +
@@ -410,12 +373,6 @@ class StarWarsIntrospectionTests : XCTestCase {
     }
 
     func testIntrospectionFieldArgsQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionFieldArgsQuery {" +
                     "    __schema {" +
                     "        queryType {" +
@@ -529,12 +486,6 @@ class StarWarsIntrospectionTests : XCTestCase {
     }
 
     func testIntrospectionDroidDescriptionQuery() throws {
-        let group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
-
-        defer {
-            XCTAssertNoThrow(try group.syncShutdownGracefully())
-        }
-
         let query = "query IntrospectionDroidDescriptionQuery {" +
                     "    __type(name: \"Droid\") {" +
                     "        name" +

Tests/GraphitiTests/StarWarsTests/StarWarsQueryTests.swift

@@ -6,7 +6,7 @@ import GraphQL
 @available(OSX 10.15, *)
 class StarWarsQueryTests : XCTestCase {
     private let service = StarWarsService()
-    private var group = MultiThreadedEventLoopGroup(numberOfThreads: 1)
+    private var group = MultiThreadedEventLoopGroup(numberOfThreads: System.coreCount)
 
     deinit {
         try? self.group.syncShutdownGracefully()