Add Swift stubs

.gitignore

@@ -0,0 +1,6 @@
+.DS_Store
+/.build
+/Packages
+/*.xcodeproj
+xcuserdata/
+protoc_plugins/

Makefile

@@ -1,6 +1,43 @@
-build:
+PROTOS    := $(shell find ./speechly -name *.proto)
+SWIFT_PROTOS_DIR :=  ./Sources/SpeechlyAPI
+SWIFT_BUILD_DIR := ./.build
+SWIFT_LIB_VERSION := 1.0.0-alpha.20
+SWIFT_PLUGINS_DIR := ./protoc_plugins
+SWIFT_PROTOC_GEN_SWIFT := $(SWIFT_PLUGINS_DIR)/bin/protoc-gen-swift
+SWIFT_PROTOC_GEN_GRPC_SWIFT := $(SWIFT_PLUGINS_DIR)/bin/protoc-gen-grpc-swift
+
+build: build-swift
 	@echo "Generating code stubs"
 	@make -C go
 	@make -C python
 	@make -C javascript
 .PHONY: build
+
+build-swift: $(SWIFT_BUILD_DIR)
+.PHONY: build-swift
+
+clean-swift:
+	@rm -rf $(SWIFT_BUILD_DIR) $(SWIFT_PROTOS_DIR) $(SWIFT_PLUGINS_DIR) || true
+.PHONY: clean-swift
+
+$(SWIFT_BUILD_DIR): $(SWIFT_PROTOS_DIR)
+	@swift build
+	@touch $@
+
+$(SWIFT_PROTOS_DIR): $(PROTOS) $(SWIFT_PLUGINS_DIR)
+	@mkdir -p $(SWIFT_PROTOS_DIR)
+	@protoc \
+		-I . \
+		--plugin=$(SWIFT_PROTOC_GEN_SWIFT) \
+		--plugin=$(SWIFT_PROTOC_GEN_GRPC_SWIFT) \
+		--swift_out="$(SWIFT_PROTOS_DIR)" \
+		--swift_opt=Visibility=Public \
+		--grpc-swift_out="$(SWIFT_PROTOS_DIR)" \
+		--grpc-swift_opt=Visibility=Public \
+		$(PROTOS)
+
+$(SWIFT_PLUGINS_DIR):
+	@mkdir $(SWIFT_PLUGINS_DIR)
+	@curl -L https://github.com/grpc/grpc-swift/releases/download/$(SWIFT_LIB_VERSION)/protoc-grpc-swift-plugins-$(SWIFT_LIB_VERSION).zip -o $(SWIFT_PLUGINS_DIR)/plugins.zip
+	@unzip $(SWIFT_PLUGINS_DIR)/plugins.zip -d $(SWIFT_PLUGINS_DIR)
+	@rm $(SWIFT_PLUGINS_DIR)/plugins.zip

Package.swift

@@ -0,0 +1,22 @@
+// swift-tools-version:5.3
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "speechly-api",
+    products: [
+        .library(name: "SpeechlyAPI", targets: ["SpeechlyAPI"]),
+    ],
+    dependencies: [
+        .package(url: "https://github.com/grpc/grpc-swift.git", from: "1.0.0-alpha.20"),
+    ],
+    targets: [
+        .target(
+            name: "SpeechlyAPI",
+            dependencies: [
+                .product(name: "GRPC", package: "grpc-swift"),
+            ]
+        ),
+    ]
+)

README.md

@@ -4,11 +4,77 @@ This repository stores the definitions and generated code for Speechly public AP
 
 Protocol buffers definitions are located in `speechly/`.
 
-Generated Go code and the module is located in `go/`, Python code and package in `python/`, Javascript code and package in `javascript/`.
+Generated Go code and the module is located in `go/`, Python code and package in `python/`, Javascript code and package in `javascript/` and Swift code in `Sources/`. Swift Package Manager requires the manifest to be in the root of the repository, hence why Swift code is not put into its dedicated subdirectory.
 
 Make sure to check language-specific READMEs.
 
 ## Building
 
 You can run the build for all languages with `make build` from the root of this repo.
 
+## Using Swift stubs
+
+You can add Swift stubs to your project using Swift Package Manager. Here's an example configuration:
+
+```swift
+// swift-tools-version:5.3
+
+import PackageDescription
+
+let package = Package(
+  name: "my-package",
+  products: [
+    .executable(name: "SomeName", targets: ["SomeTarget"]),
+  ],
+  dependencies: [
+    .package(url: "https://github.com/speechly/api.git", from: "1.0.0-alpha.1"),
+  ],
+  targets: [
+    .target(
+      name: "SomeTarget",
+      dependencies: [
+        .product(name: "SpeechlyAPI", package: "speechly-api"),
+      ]),
+  ]
+)
+```
+
+Thereafter you can use the stubs in your code (you will most likely need to add `grpc-swift` and `swift-nio` dependencies to write gRPC clients):
+
+```swift
+import NIO
+import GRPC
+import SpeechlyAPI
+
+class IdentityClient {
+  let client: SpeechlyAPI.Speechly_Identity_V1_IdentityClient
+
+  init() {
+    let group = GRPC.PlatformSupport.makeEventLoopGroup(loopCount: 1)
+    let channel = GRPC.ClientConnection.secure(group: group).connect(host: "api.speechly.com", port: 443)
+
+    self.client = SpeechlyAPI.Speechly_Identity_V1_IdentityClient(channel: channel)
+  }
+
+  func login(appId: String, deviceId: String) -> NIO.EventLoopFuture<String> {
+    let request = SpeechlyAPI.Speechly_Identity_V1_LoginRequest.with {
+      $0.appID = appId
+      $0.deviceID = deviceId
+    }
+
+    return self.client.login(request).response.map({ (response: SpeechlyAPI.Speechly_Identity_V1_LoginResponse) -> String in
+      return response.token
+    })
+  }
+
+  deinit {
+    let future = self.client.channel.close()
+
+    do {
+      try future.wait()
+    } catch {
+      print("Error closing gRPC channel: \(error)")
+    }
+  }
+}
+```