# Hello World

This example demonstrates the canonical "Hello World" in gRPC.

## Overview

A "hello-world" command line tool that uses generated stubs for the 'Greeter'
service which allows you to start a server and to make requests against it.

The tool uses the [SwiftNIO](https://github.com/grpc/grpc-swift-nio-transport)
HTTP/2 transport.

## Prerequisites

You must have the Protocol Buffers compiler (`protoc`) installed. You can find
the instructions for doing this in the [gRPC Swift Protobuf documentation][0].
The `swift` commands below are all prefixed with `PROTOC_PATH=$(which protoc)`,
this is to let the build system know where `protoc` is located so that it can
generate stubs for you. You can read more about it in the [gRPC Swift Protobuf
documentation][1].

## Usage

Build and run the server using the CLI:

```console
$ PROTOC_PATH=$(which protoc) swift run hello-world serve
Greeter listening on [ipv4]127.0.0.1:31415
```

Use the CLI to send a request to the service:

```console
$ PROTOC_PATH=$(which protoc) swift run hello-world greet
Hello, stranger
```

Send the name of the greetee in the request by specifying a `--name`:

```console
$ PROTOC_PATH=$(which protoc) swift run hello-world greet --name "PanCakes 🐶"
Hello, PanCakes 🐶
```

[0]: https://swiftpackageindex.com/grpc/grpc-swift-protobuf/documentation/grpcprotobuf/installing-protoc
[1]: https://swiftpackageindex.com/grpc/grpc-swift-protobuf/documentation/grpcprotobuf/generating-stubs