Add option to include OpenAPI generator (#18)

Author: adam-fowler

Package.swift

@@ -11,16 +11,36 @@ let package = Package(
     ],
     dependencies: [
         .package(url: "https://github.com/hummingbird-project/hummingbird.git", from: "2.0.0"),
-        .package(url: "https://github.com/apple/swift-argument-parser.git", from: "1.3.0")
+        .package(url: "https://github.com/apple/swift-argument-parser.git", from: "1.3.0"),
+{{#HB_OPENAPI}}
+        .package(url: "https://github.com/apple/swift-openapi-generator", from: "1.6.0"),
+        .package(url: "https://github.com/apple/swift-openapi-runtime", from: "1.7.0"),
+        .package(url: "https://github.com/swift-server/swift-openapi-hummingbird.git", from: "2.0.1"),
+{{/HB_OPENAPI}}
     ],
     targets: [
         .executableTarget(name: "{{HB_EXECUTABLE_NAME}}",
             dependencies: [
                 .product(name: "ArgumentParser", package: "swift-argument-parser"),
                 .product(name: "Hummingbird", package: "hummingbird"),
+{{#HB_OPENAPI}}
+                .byName(name: "{{HB_EXECUTABLE_NAME}}API"),
+                .product(name: "OpenAPIRuntime", package: "swift-openapi-runtime"),
+                .product(name: "OpenAPIHummingbird", package: "swift-openapi-hummingbird"),
+{{/HB_OPENAPI}}
             ],
             path: "Sources/App"
         ),
+{{#HB_OPENAPI}}
+        .target(
+            name: "{{HB_EXECUTABLE_NAME}}API",
+            dependencies: [
+                .product(name: "OpenAPIRuntime", package: "swift-openapi-runtime")
+            ],
+            path: "Sources/AppAPI",
+            plugins: [.plugin(name: "OpenAPIGenerator", package: "swift-openapi-generator")],
+        ),
+{{/HB_OPENAPI}}
         .testTarget(name: "{{HB_EXECUTABLE_NAME}}Tests",
             dependencies: [
                 .byName(name: "{{HB_EXECUTABLE_NAME}}"),

Sources/App/APIImplementation.swift

@@ -0,0 +1,10 @@
+{{#HB_OPENAPI}}
+import AppAPI
+import OpenAPIRuntime
+
+struct APIImplementation: APIProtocol {
+    func getHello(_ input: AppAPI.Operations.GetHello.Input) async throws -> AppAPI.Operations.GetHello.Output {
+        return .ok(.init(body: .plainText("Hello!")))
+    }
+}
+{{/HB_OPENAPI}}

Sources/App/Application+build.swift

@@ -1,5 +1,8 @@
 import Hummingbird
 import Logging
+{{#HB_OPENAPI}}
+import OpenAPIHummingbird
+{{/HB_OPENAPI}}
 
 /// Application arguments protocol. We use a protocol so we can call
 /// `buildApplication` inside Tests as well as in the App executable. 
@@ -26,7 +29,7 @@ public func buildApplication(_ arguments: some AppArguments) async throws -> som
             .info
         return logger
     }()
-    let router = buildRouter()
+    let router = try buildRouter()
     let app = Application(
         router: router,
         configuration: .init(
@@ -39,16 +42,27 @@ public func buildApplication(_ arguments: some AppArguments) async throws -> som
 }
 
 /// Build router
-func buildRouter() -> Router<AppRequestContext> {
+func buildRouter() throws -> Router<AppRequestContext> {
     let router = Router(context: AppRequestContext.self)
     // Add middleware
     router.addMiddleware {
         // logging middleware
         LogRequestsMiddleware(.info)
+{{#HB_OPENAPI}}
+        // store request context in TaskLocal
+        OpenAPIRequestContextMiddleware()
+{{/HB_OPENAPI}}
     }
+{{#HB_OPENAPI}}
+    // Add OpenAPI handlers
+    let api = APIImplementation()
+    try api.registerHandlers(on: router)
+{{/HB_OPENAPI}}
+{{^HB_OPENAPI}}
     // Add default endpoint
     router.get("/") { _,_ in
         return "Hello!"
     }
+{{/HB_OPENAPI}}
     return router
 }

Sources/App/OpenAPIRequestContextMiddleware.swift

@@ -0,0 +1,21 @@
+{{#HB_OPENAPI}}
+import Hummingbird
+
+extension AppRequestContext {
+    @TaskLocal static var current: AppRequestContext?
+}
+
+/// Middleware that adds the RequestContext as a TaskLocal so it is accessible from OpenAPI handlers.
+///
+/// This middleware should be the last in the middleware chain to ensure all edits to the RequestContext
+/// are passed to the Task Local
+struct OpenAPIRequestContextMiddleware: RouterMiddleware {
+    typealias Context = AppRequestContext
+
+    func handle(_ request: Request, context: Context, next: (Request, Context) async throws -> Response) async throws -> Response {
+        try await AppRequestContext.$current.withValue(context) {
+            try await next(request, context)
+        }
+    }
+}
+{{/HB_OPENAPI}}

Sources/AppAPI/AppAPI.swift

@@ -0,0 +1,3 @@
+{{#HB_OPENAPI}}
+// Empty swift file, needed for SwiftPM to recognize this is a Swift target
+{{/HB_OPENAPI}}

Sources/AppAPI/openapi-generator-config.yaml

@@ -0,0 +1,7 @@
+{{#HB_OPENAPI}}
+generate:
+  - types
+  - server
+accessModifier: package
+namingStrategy: idiomatic
+{{/HB_OPENAPI}}

Sources/AppAPI/openapi.yaml

@@ -0,0 +1,20 @@
+{{#HB_OPENAPI}}
+openapi: '3.1.0'
+info:
+  title: AppService
+  version: 1.0.0
+servers:
+  - url: https://example.com/api
+    description: App service deployment.
+paths:
+  /:
+    get:
+      operationId: getHello
+      responses:
+        '200':
+          description: Hello!
+          content:
+            text/plain:
+              schema:
+                type: string
+{{/HB_OPENAPI}}

configure.sh

@@ -84,7 +84,9 @@ run_mustache()
         if ! grep -q '[^[:space:]]' "$TEMP_FILE" ; then
             echo "Removing $FILE"
             rm "$TEMP_FILE"
-            rm "$TARGET_FOLDER/$FILE"
+            if [ "$IN_PLACE_EDIT" = true ]; then
+                rm "$TARGET_FOLDER/$FILE"
+            fi
         else
             echo "Copying $FILE"
             mv -f "$TEMP_FILE" "$TARGET_FOLDER/$FILE"
@@ -156,8 +158,15 @@ if [[ "$HB_EXECUTABLE_NAME" =~ [^a-zA-Z0-9_] ]]; then
     exitWithError "Invalid executable name: $HB_EXECUTABLE_NAME"
 fi
 
+echo -n "Do you want to use the OpenAPI generator: "
+read_yes_no "no"
+if [[ "$READ_INPUT_RETURN" == "yes" ]]; then
+    export HB_OPENAPI="yes"
+    mkdir -p "$TARGET_FOLDER"/Sources/AppAPI
+fi
+
 echo -n "Include Visual Studio Code snippets: "
-read_yes_no "yes"
+read_yes_no "no"
 if [[ "$READ_INPUT_RETURN" == "yes" ]]; then
     export HB_VSCODE_SNIPPETS="yes"
 fi