Update and add examples to new APIs (#228)

* take advantage of @main where possible
* move the top level Sample code to the examples subdirectory
* extract a few examples form the "LambdaFunctions" directory (which is really a deployment demo) and move them to the top level Examples directory
*  rename "LambdaFunctions" examples as "Deployments" to make their intent clearer
* add a sample that demonstrates how to test a lambda now that SwiftPM can test executables directly
* update the test-sample docker setup to build & test th new samples
* fix a few typos and In/Out typealias left overs
* remove LinuxMain since its no longer required

Author: tomerd

Examples/Benchmark/Package.swift

@@ -0,0 +1,28 @@
+// swift-tools-version:5.5
+
+import PackageDescription
+
+let package = Package(
+    name: "swift-aws-lambda-runtime-example",
+    platforms: [
+        .macOS(.v12),
+    ],
+    products: [
+        .executable(name: "MyLambda", targets: ["MyLambda"]),
+    ],
+    dependencies: [
+        // this is the dependency on the swift-aws-lambda-runtime library
+        // in real-world projects this would say
+        // .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime.git", from: "1.0.0")
+        .package(name: "swift-aws-lambda-runtime", path: "../.."),
+    ],
+    targets: [
+        .executableTarget(
+            name: "MyLambda",
+            dependencies: [
+                .product(name: "AWSLambdaRuntimeCore", package: "swift-aws-lambda-runtime"),
+            ],
+            path: "."
+        ),
+    ]
+)

Examples/Benchmark/main.swift

@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftAWSLambdaRuntime open source project
+//
+// Copyright (c) 2020 Apple Inc. and the SwiftAWSLambdaRuntime project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftAWSLambdaRuntime project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import AWSLambdaRuntimeCore
+import NIOCore
+
+// If you would like to benchmark Swift's Lambda Runtime,
+// use this example which is more performant.
+// `EventLoopLambdaHandler` does not offload the Lambda processing to a separate thread
+// while the closure-based handlers do.
+
+struct MyLambda: EventLoopLambdaHandler {
+    typealias Event = String
+    typealias Output = String
+
+    func handle(_ event: String, context: Lambda.Context) -> EventLoopFuture<String> {
+        context.eventLoop.makeSucceededFuture("hello, world!")
+    }
+}
+
+Lambda.run { $0.eventLoop.makeSucceededFuture(MyLambda()) }

Examples/LambdaFunctions/.dockerignore renamed to Examples/Deployment/.dockerignore

@@ -0,0 +1,3 @@
+FROM swift:5.5-amazonlinux2
+
+RUN yum -y install zip

Examples/Deployment/Dockerfile

@@ -13,9 +13,6 @@ let package = Package(
         // good for benchmarking
         .executable(name: "Benchmark", targets: ["Benchmark"]),
         // demonstrate different types of error handling
-        .executable(name: "ErrorHandling", targets: ["ErrorHandling"]),
-        // fully featured example with domain specific business logic
-        .executable(name: "CurrencyExchange", targets: ["CurrencyExchange"]),
     ],
     dependencies: [
         // this is the dependency on the swift-aws-lambda-runtime library
@@ -30,11 +27,5 @@ let package = Package(
         .executableTarget(name: "HelloWorld", dependencies: [
             .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
         ]),
-        .executableTarget(name: "ErrorHandling", dependencies: [
-            .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
-        ]),
-        .executableTarget(name: "CurrencyExchange", dependencies: [
-            .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
-        ]),
     ]
 )

Examples/LambdaFunctions/Package.swift renamed to Examples/Deployment/Package.swift

@@ -1,14 +1,14 @@
-# Lambda Functions Examples
+# Deployment Examples
 
 This sample project is a collection of Lambda functions that demonstrates
 how to write a simple Lambda function in Swift, and how to package and deploy it
 to the AWS Lambda platform.
 
-The scripts are prepared to work from the `LambdaFunctions` folder.
+The scripts are prepared to work from the `Deployment` folder.
 
 ```
 git clone https://github.com/swift-server/swift-aws-lambda-runtime.git
-cd swift-aws-lambda-runtime/Examples/LambdaFunctions
+cd swift-aws-lambda-runtime/Examples/Deployment
 ```
 
 Note: The example scripts assume you have [jq](https://stedolan.github.io/jq/download/) command line tool installed.
@@ -27,7 +27,7 @@ Steps to deploy this sample to AWS Lambda using the AWS CLI:
   ./scripts/deploy.sh
   ```
 
-  Notes: 
+  Notes:
   - This script assumes you have AWS CLI installed and credentials setup in `~/.aws/credentials`.
   - The default lambda function name is `SwiftSample`. You can specify a different one updating `lambda_name` in `deploy.sh`
   - Update `s3_bucket=swift-lambda-test` in `deploy.sh` before running (AWS S3 buckets require a unique global name)
@@ -129,7 +129,7 @@ The `serverless-deploy.sh` script passes through any parameters to the Serverles
 
 For the APIGateway sample:
 
-The Serverless template will provide an endpoint which you can use to test the Lambda. 
+The Serverless template will provide an endpoint which you can use to test the Lambda.
 
 Outuput example:
 
@@ -174,4 +174,4 @@ For all other samples use the AWS Lambda console.
   ./scripts/serverless-remove.sh
   ```
 
-The script will ask you which sample Lambda you wish to remove from the previous depolyment.
+The script will ask you which sample Lambda you wish to remove from the previous deployment.

Examples/LambdaFunctions/README.md renamed to Examples/Deployment/README.md

@@ -19,7 +19,6 @@ import NIO
 // use this example which is more performant.
 // `EventLoopLambdaHandler` does not offload the Lambda processing to a separate thread
 // while the closure-based handlers do.
-Lambda.run { $0.eventLoop.makeSucceededFuture(BenchmarkHandler()) }
 
 struct BenchmarkHandler: EventLoopLambdaHandler {
     typealias Event = String
@@ -29,3 +28,5 @@ struct BenchmarkHandler: EventLoopLambdaHandler {
         context.eventLoop.makeSucceededFuture("hello, world!")
     }
 }
+
+Lambda.run { $0.eventLoop.makeSucceededFuture(BenchmarkHandler()) }

Examples/LambdaFunctions/Sources/Benchmark/main.swift renamed to Examples/Deployment/Sources/Benchmark/main.swift

@@ -27,13 +27,13 @@ echo "done"
 echo "-------------------------------------------------------------------------"
 echo "building \"$executable\" lambda"
 echo "-------------------------------------------------------------------------"
-docker run --rm -v "$workspace":/workspace -w /workspace/Examples/LambdaFunctions builder \
+docker run --rm -v "$workspace":/workspace -w /workspace/Examples/Deployment builder \
        bash -cl "swift build --product $executable -c release"
 echo "done"
 
 echo "-------------------------------------------------------------------------"
 echo "packaging \"$executable\" lambda"
 echo "-------------------------------------------------------------------------"
-docker run --rm -v "$workspace":/workspace -w /workspace/Examples/LambdaFunctions builder \
+docker run --rm -v "$workspace":/workspace -w /workspace/Examples/Deployment builder \
        bash -cl "./scripts/package.sh $executable"
 echo "done"

Examples/LambdaFunctions/Sources/HelloWorld/HelloWorldHandler.swift renamed to Examples/Deployment/Sources/HelloWorld/HelloWorldHandler.swift

@@ -0,0 +1,32 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the SwiftAWSLambdaRuntime open source project
+//
+// Copyright (c) 2021 Apple Inc. and the SwiftAWSLambdaRuntime project authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See CONTRIBUTORS.txt for the list of SwiftAWSLambdaRuntime project authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import AWSLambdaRuntime
+
+// in this example we are receiving and responding with strings
+
+@main
+struct MyLambda: LambdaHandler {
+    typealias Event = String
+    typealias Output = String
+
+    init(context: Lambda.InitializationContext) async throws {
+        // setup your resources that you want to reuse for every invocation here.
+    }
+
+    func handle(_ input: String, context: Lambda.Context) async throws -> String {
+        // as an example, respond with the input's reversed
+        String(input.reversed())
+    }
+}

Examples/LambdaFunctions/scripts/SAM/APIGateway-template.yml renamed to Examples/Deployment/scripts/SAM/APIGateway-template.yml

@@ -0,0 +1,28 @@
+// swift-tools-version:5.5
+
+import PackageDescription
+
+let package = Package(
+    name: "swift-aws-lambda-runtime-example",
+    platforms: [
+        .macOS(.v12),
+    ],
+    products: [
+        .executable(name: "MyLambda", targets: ["MyLambda"]),
+    ],
+    dependencies: [
+        // this is the dependency on the swift-aws-lambda-runtime library
+        // in real-world projects this would say
+        // .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime.git", from: "1.0.0")
+        .package(name: "swift-aws-lambda-runtime", path: "../.."),
+    ],
+    targets: [
+        .executableTarget(
+            name: "MyLambda",
+            dependencies: [
+                .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
+            ],
+            path: "."
+        ),
+    ]
+)

Examples/LambdaFunctions/scripts/SAM/Benchmark-template.yml renamed to Examples/Deployment/scripts/SAM/Benchmark-template.yml

@@ -17,7 +17,7 @@ import AWSLambdaRuntime
 // MARK: - Run Lambda
 
 @main
-struct ErrorsHappenHandler: LambdaHandler {
+struct MyLambda: LambdaHandler {
     typealias Event = Request
     typealias Output = Response
 

Examples/LambdaFunctions/scripts/SAM/HelloWorld-template.yml renamed to Examples/Deployment/scripts/SAM/HelloWorld-template.yml

@@ -0,0 +1,28 @@
+// swift-tools-version:5.5
+
+import PackageDescription
+
+let package = Package(
+    name: "swift-aws-lambda-runtime-example",
+    platforms: [
+        .macOS(.v12),
+    ],
+    products: [
+        .executable(name: "MyLambda", targets: ["MyLambda"]),
+    ],
+    dependencies: [
+        // this is the dependency on the swift-aws-lambda-runtime library
+        // in real-world projects this would say
+        // .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime.git", from: "1.0.0")
+        .package(name: "swift-aws-lambda-runtime", path: "../.."),
+    ],
+    targets: [
+        .executableTarget(
+            name: "MyLambda",
+            dependencies: [
+                .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
+            ],
+            path: "."
+        ),
+    ]
+)

Examples/LambdaFunctions/scripts/build-and-package.sh renamed to Examples/Deployment/scripts/build-and-package.sh

@@ -24,7 +24,7 @@ import Logging
 // MARK: - Run Lambda
 
 @main
-struct CurrencyExchangeHandler: LambdaHandler {
+struct MyLambda: LambdaHandler {
     typealias Event = Request
     typealias Output = [Exchange]
 

Examples/LambdaFunctions/scripts/config.sh renamed to Examples/Deployment/scripts/config.sh

@@ -0,0 +1,28 @@
+// swift-tools-version:5.5
+
+import PackageDescription
+
+let package = Package(
+    name: "swift-aws-lambda-runtime-example",
+    platforms: [
+        .macOS(.v12),
+    ],
+    products: [
+        .executable(name: "MyLambda", targets: ["MyLambda"]),
+    ],
+    dependencies: [
+        // this is the dependency on the swift-aws-lambda-runtime library
+        // in real-world projects this would say
+        // .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime.git", from: "1.0.0")
+        .package(name: "swift-aws-lambda-runtime", path: "../.."),
+    ],
+    targets: [
+        .executableTarget(
+            name: "MyLambda",
+            dependencies: [
+                .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
+            ],
+            path: "."
+        ),
+    ]
+)

Examples/LambdaFunctions/scripts/deploy.sh renamed to Examples/Deployment/scripts/deploy.sh

@@ -2,7 +2,7 @@
 //
 // This source file is part of the SwiftAWSLambdaRuntime open source project
 //
-// Copyright (c) 2017-2020 Apple Inc. and the SwiftAWSLambdaRuntime project authors
+// Copyright (c) 2021 Apple Inc. and the SwiftAWSLambdaRuntime project authors
 // Licensed under Apache License v2.0
 //
 // See LICENSE.txt for license information
@@ -13,7 +13,6 @@
 //===----------------------------------------------------------------------===//
 
 import AWSLambdaRuntime
-import NIOCore
 
 struct Request: Codable {
     let body: String
@@ -24,23 +23,19 @@ struct Response: Codable {
 }
 
 // in this example we are receiving and responding with codables. Request and Response above are examples of how to use
-// codables to model your reqeuest and response objects
-struct Handler: EventLoopLambdaHandler {
+// codables to model your request and response objects
+
+@main
+struct MyLambda: LambdaHandler {
     typealias Event = Request
     typealias Output = Response
 
-    func handle(_ event: Request, context: Lambda.Context) -> EventLoopFuture<Response> {
+    init(context: Lambda.InitializationContext) async throws {
+        // setup your resources that you want to reuse for every invocation here.
+    }
+
+    func handle(_ event: Request, context: Lambda.Context) async throws -> Response {
         // as an example, respond with the input event's reversed body
-        context.eventLoop.makeSucceededFuture(Response(body: String(event.body.reversed())))
+        Response(body: String(event.body.reversed()))
     }
 }
-
-Lambda.run { $0.eventLoop.makeSucceededFuture(Handler()) }
-
-// MARK: - this can also be expressed as a closure:
-
-/*
- Lambda.run { (_, request: Request, callback) in
-   callback(.success(Response(body: String(request.body.reversed()))))
- }
- */

Examples/LambdaFunctions/scripts/package.sh renamed to Examples/Deployment/scripts/package.sh

@@ -0,0 +1,28 @@
+// swift-tools-version:5.5
+
+import PackageDescription
+
+let package = Package(
+    name: "swift-aws-lambda-runtime-example",
+    platforms: [
+        .macOS(.v12),
+    ],
+    products: [
+        .executable(name: "MyLambda", targets: ["MyLambda"]),
+    ],
+    dependencies: [
+        // this is the dependency on the swift-aws-lambda-runtime library
+        // in real-world projects this would say
+        // .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime.git", from: "1.0.0")
+        .package(name: "swift-aws-lambda-runtime", path: "../.."),
+    ],
+    targets: [
+        .executableTarget(
+            name: "MyLambda",
+            dependencies: [
+                .product(name: "AWSLambdaRuntime", package: "swift-aws-lambda-runtime"),
+            ],
+            path: "."
+        ),
+    ]
+)