feat(doc): create README

README.md

@@ -0,0 +1,91 @@
+# Reflect API UNIX socket client for PHP
+
+Make requests to endpoints created with the [Reflect API framework](https://github.com/victorwesterlund/reflect) running the same machine.
+
+---
+
+Make a request with `SocketClient->call()`. It will return the response as an array of length 2.
+- The first value is the HTTP-equivalent response code.
+- The second value is the response body
+
+```php
+$client = new Reflect\SocketClient("/path/to/socket");
+
+$client->call("foo", Method::GET); // (array) [200, "bar"]
+$client->call("foo", Method::POST, [
+  "foo" => "bar"
+]); // (array) [201, "Created"]
+
+// etc..
+```
+
+## How to use
+
+Requires PHP 8.1 or newer, and of course an instance of the [Reflect socket server](https://github.com/VictorWesterlund/reflect/wiki/UNIX-Sockets) running on the same machine.
+
+1. **Install with composer**
+
+   ```
+   composer require reflect/socket-server
+   ```
+   
+2. **Initialize the class**
+
+   ```php
+   require_once "/vendor/autoload.php";
+   
+   $client = new Reflect\SocketClient("/path/to/socket");
+   ```
+   
+3. **Make API request**
+
+   Use the `call()` method to perform a request
+   
+   ```php
+   $client->call("foo?bar=baz", Method::GET);
+   ```
+   
+   Argument index|Type|Required|Description
+   --|--|--|--
+   0|String|Yes|Fully qualified pathname and query params of the endpoint to call
+   1|Method|Yes|A supported [Reflect HTTP method](https://github.com/VictorWesterlund/reflect/wiki/Supported-technologies#http-request-methods) (eg. `Method::GET`)
+   2|Array|No|An optional indexed, associative, or multidimensional array that will be sent as the request body as `Content-Type: application/json`
+   
+   The `call()` function will return an array of length 2 wil the following information
+   
+   Index|Type|Description
+   --|--|--
+   0|Int|HTTP-equivalent response code (eg. `200` or `404`)
+   1|String/Array|Contains the response body as either a string, or array if the response `Content-Type` header is `application/json`
+   
+## How to use (CLI)
+
+You can also run this from the command line with
+
+```
+php client <socket_file> <endpoint> <http_method> [payload]
+```
+
+and it will return a serialized JSON array with the same structure as described in the `SocketClient->call()` return.
+
+*Example*
+```sh
+php client "/run/reflect.sock" "foo?bar=biz" "POST" "[\"foo\" => \"bar\"]" # (string) [201, \"Created\"]
+```
+
+---
+
+Requires PHP CLI 8.1 or greater, and of course an instance of the [Reflect socket server](https://github.com/VictorWesterlund/reflect/wiki/UNIX-Sockets) running on the same machine.
+
+1. **Clone repo**
+
+   ```
+   git clone https://github.com/victorwesterlund/reflect-socket-client-php
+   ```
+   
+2. **Run from command line**
+
+   ```
+   cd reflect-socket-client-php
+   php client <socket_file> <endpoint> <http_method> [payload]
+   ```