The `api` package (v3.0) allows you to easily create and manage an API for your applications. It can be used as an HTTP API (REST, or other kind), and you can use it as an internal core for your system.
The aim of this package is to make your life easier working with APIs and internal delegation. The only things you have to do is to implement your processes and write the configuration, the package will do the rest.
The api is made of paths that binds to a *php class*, each `path` can manage multiple **HTTP METHODS** each will correspond to a *method* of the bound class.
Each module's implementation is represented as a **file** so as a **class** located in `/build/api/module/`. In order for the autoloader to work, you must name the **file** the same name as the **class**.
### Method implementation
Each method is represented as a method in its module's class.
### Input arguments
Arguments are passed to the method as a single argument which an associative array according to the documentation.
_Notes_:
* Optional parameters if not given are set to `null`
* parameters of type `FILE` are given by reference but the use is the same as normal parameters
* URL parameters are called `URL_0`, `URL_1` and so on according to their order.
### Ouput required
You must return an associative array containing at least the field `error` containing an instance of `/api/core/Error`, then you can add whatever you want to return in the array.
If you don't return the 'error' field, by default it is set to `new Error(Err::Success)`.
> # **V.** Class documentation
> ## **1** Request
### Attributes
The attribute `error` will contain the current `Error` instance.
```php
<?php
public $error;
```
### Methods
Creates a new `Request` object, you must give it a path following the pattern "module/method", the params must be an associative array. Note that the path can be inside the `$params` variable.
It checks missing params and each needed params' type according to the **Checker** implementation (cf. [Checker](#4-checker)). It also checks the permissions you have according to the **AuthSystem** implementation (cf. [AuthSystem](#1-permissions--authsystem)).
```php
<?php
public function __construct(String $path, Array $params) : Request;
```
Creates a new `Request` object but from the URL. It will seek for the *path* in the URL, then in the data. (it will call itself the **\_\_construct()** method).
```php
<?php
public static function remote(String $url, Array $data) : Request;
```
Registers the **AuthSystem** you want, must be done before any construction.
```php
<?php
public static function setAuthSystem(Request $instance) : bool;
```
Executes the current `Request` object and returns a `Response` object.
```php
<?php
public function dispatch() : Response;
```
Same as `dispatch()` but manages the **download** option (cf. [Configuration](#iii-configuration)). It will use 2 of the parameters you must return on success : `body`, and `headers`. The first one must contain the content of the file to create, the second the headers in an associative array.
The call will become the file itself.
Note: If the `HTTP_X_REQUESTED_WITH` header is present, it will create the downloadable file as **/tmp/download_{some\_hash}** and return a normal `Response` object with the field `link` containing the file absolute path.
```php
<?php
public function download() : null;
public function download() : Response; // if called by Ajax
```
> ## **2** Response
### Attributes
The attribute `error` will contain the current `Error` instance.
```php
<?php
public $error;
```
### Methods
Returns an associative array containing the whole response data (excluding the error).
```php
<?php
public function getAll() : Array;
```
Returns only the field from the response data (if it exists).
```php
<?php
public function get(String $key) : mixed; // on success
public function get(String $key) : null; // on error
```
Sets the `HTTP_CODE` according to the `Error` argument, also it sets the header for **application/json**.
It can be used for simple API response, it will add the *"error"* and *"ErrorDescription"* fields to the data and set the headers so you can display the result of the API call.
```php
<?php
public function serialize() : String;
```
> ## **4** Checker
`Checker` checks the input values according to the type given in the configuration.
The default types below are available in the default package.
To add a new type, just open the file `/build/api/Checker.php` and add an entry in the `switch` statement.
### Default types
|Type|Example|Description|
|---|---|---|
|`mixed`|`[9,"a"]`, `"a"`|Any content (can be simple or complex)|
|`id`|`10`, `"23"`|Positive integer number between `0` and `2147483647`|
|`numeric`|`-10.2`, `"23"`|Any number, `null` and the string `"null"`|
|`text`|`"Hello!"`|String that can be of any length (even empty)|
|`hash`|`"4612473aa81f93a878674f9ebffa8d63a1b51ea28dcdcdb1e89eb512aae9b77e"`|String with a length of 40 or 64, containing only hexadecimal characters|
|`alphanumeric`|`"abc029.-sd9"`|String containing only alphanumeric, ___, _-_, and _._ characters|
|`letters`|`"abc -sd"`|String containing only letters, _-_, and space characters|
|`mail`|`"a.b@c.def"`|Valid email address|
|`number`|`0102030405`|Phone number, following formats allowed : `06`, `+336`, `+33 6`|
|`array`|`[1, 3]`|Non-empty array|
|`object`|_works only within php_|Non-empty object|
|`boolean`|`true`, `false`|Boolean|
|`varchar(a,b)`|`"Hello!"`|String with a length between `a` and `b` (included)|
|`varchar(a,b,c)`|`"abc"`|String with a length between `a` and `b` (included) and matching the `c` type|
### Complex type : chainable array
|Type|Sub-Type|Description|
|---|---|---|
|`array<a>`|`a`|Array containing only entries matching the type `a`|
> **Note:** It is possible to chain `array` type as many as needed.
**Ex.:** `array<array<id>>` - Will match array only containing arrays that only contains `id` entries.
> ## **5** Advanced
### Before and After scripts
Each time a **method** is called, the api **creates an instance** from the class, and after the execution, the class is **destroyed**. So you can implement the methods `__construct` and `__destruct` to add before and after scripts.
