miniflux-legacy/vendor/fguillot/json-rpc/README.markdown

JsonRPC PHP Client and Server

A simple Json-RPC client/server that just works.

Features

• JSON-RPC 2.0 protocol only
• The server support batch requests and notifications
• Authentication and IP based client restrictions
• Minimalist: there is only 2 files
• Fully unit tested
• License: MIT

Requirements

• The only dependency is the cURL extension
• PHP >= 5.3

Author

Frédéric Guillot

Installation with Composer

composer require fguillot/json-rpc dev-master

Examples

Server

Callback binding:

<?php

use JsonRPC\Server;

$server = new Server;

// Procedures registration

$server->register('addition', function ($a, $b) {
    return $a + $b;
});

$server->register('random', function ($start, $end) {
    return mt_rand($start, $end);
});

// Return the response to the client
echo $server->execute();

?>

Class/Method binding:

<?php

use JsonRPC\Server;

class Api
{
    public function doSomething($arg1, $arg2 = 3)
    {
        return $arg1 + $arg2;
    }
}

$server = new Server;

// Bind the method Api::doSomething() to the procedure myProcedure
$server->bind('myProcedure', 'Api', 'doSomething');

// Use a class instance instead of the class name
$server->bind('mySecondProcedure', new Api, 'doSomething');

// The procedure and the method are the same
$server->bind('doSomething', 'Api');

// Attach the class, client will be able to call directly Api::doSomething()
$server->attach(new Api);

echo $server->execute();

?>

Before callback:

Before each procedure execution, a custom method can be called.

This method receive the following arguments: $username, $password, $class, $method.

<?php

use JsonRPC\Server;
use JsonRPC\AuthenticationFailure;

class Api
{
    public function beforeProcedure($username, $password, $class, $method)
    {
        if ($login_condition_failed) {
            throw new AuthenticationFailure('Wrong credentials!');
        }
    }

    public function addition($a, $b)
    {
        return $a + $b;
    }
}

$server = new Server;
$server->authentication(['myuser' => 'mypassword']);

// Register the before callback
$server->before('beforeProcedure');

$server->attach(new Api);

echo $server->execute();

?>

You can use this method to implements a custom authentication system or anything else. If you would like to reject the authentication, you can throw the exception JsonRPC\AuthenticationFailure.

Client

Example with positional parameters:

<?php

use JsonRPC\Client;

$client = new Client('http://localhost/server.php');
$result = $client->execute('addition', [3, 5]);

var_dump($result);

Example with named arguments:

<?php

use JsonRPC\Client;

$client = new Client('http://localhost/server.php');
$result = $client->execute('random', ['end' => 10, 'start' => 1]);

var_dump($result);

Arguments are called in the right order.

Examples with shortcut methods:

<?php

use JsonRPC\Client;

$client = new Client('http://localhost/server.php');
$result = $client->random(50, 100);

var_dump($result);

The example above use positional arguments for the request and this one use named arguments:

$result = $client->random(['end' => 10, 'start' => 1]);

Client batch requests

Call several procedures in a single HTTP request:

<?php

use JsonRPC\Client;

$client = new Client('http://localhost/server.php');

$results = $client->batch()
                  ->foo(['arg1' => 'bar'])
                  ->random(1, 100)
                  ->add(4, 3)
                  ->execute('add', [2, 5])
                  ->send();

print_r($results);

All results are stored at the same position of the call.

Client exceptions

• BadFunctionCallException: Procedure not found on the server
• InvalidArgumentException: Wrong procedure arguments
• RuntimeException: Protocol error, authentication failure or connection failure, the message describe the exact error

Enable client debugging

You can enable the debug to see the JSON request and response:

<?php

use JsonRPC\Client;

$client = new Client('http://localhost/server.php');
$client->debug = true;

The debug output is sent to the PHP's system logger. You can configure the log destination in your php.ini.

Output example:

==> Request:
{
    "jsonrpc": "2.0",
    "method": "removeCategory",
    "id": 486782327,
    "params": [
        1
    ]
}
==> Response:
{
    "jsonrpc": "2.0",
    "id": 486782327,
    "result": true
}

IP based client restrictions

The server can allow only some IP adresses:

<?php

use JsonRPC\Server;

$server = new Server;

// IP client restrictions
$server->allowHosts(['192.168.0.1', '127.0.0.1']);

// Procedures registration

[...]

// Return the response to the client
echo $server->execute();

If the client is blocked, you got a 403 Forbidden HTTP response.

HTTP Basic Authentication

If you use HTTPS, you can allow client by using a username/password.

<?php

use JsonRPC\Server;

$server = new Server;

// List of users to allow
$server->authentication(['user1' => 'password1', 'user2' => 'password2']);

// Procedures registration

[...]

// Return the response to the client
echo $server->execute();

On the client, set credentials like that:

<?php

use JsonRPC\Client;

$client = new Client('http://localhost/server.php');
$client->authentication('user1', 'password1');

If the authentication failed, the client throw a RuntimeException.

Using an alternative authentication header:

use JsonRPC\Server;

$server = new Server;
$server->setAuthenticationHeader('X-Authentication');
$server->authentication(['myusername' => 'mypassword']);

The example above will use the HTTP header X-Authentication instead of the standard Authorization: Basic [BASE64_CREDENTIALS]. The username/password values need be encoded in base64: base64_encode('username:password').

Exceptions

If you want to send an error to the client you can throw an exception. You should configure which exceptions should be relayed to the client first:

<?php

use JsonRPC\Server;
class MyException extends RuntimeException {};

$server = new Server;

// Exceptions that should be relayed to the client, if they occur
$server->attachException('MyException');

// Procedures registration

[...]

// Return the response to the client
echo $server->execute();

Then you can throw that exception inside your procedure:

throw new MyException("An error occured", 123);

To relay all exceptions regardless of type, leave out the exception class name:

$server->attachException();