如果您正在使用Symfony，有一个很棒的rest客户端包，它甚至包含了所有~100个异常，并抛出它们，而不是返回一些毫无意义的错误代码+消息。

你真的应该检查一下: https://github.com/CircleOfNice/CiRestClientBundle

我喜欢它的界面:

try {
    $restClient = new RestClient();
    $response   = $restClient->get('http://www.someUrl.com');
    $statusCode = $response->getStatusCode();
    $content    = $response->getContent();
} catch(OperationTimedOutException $e) {
    // do something
}

适用于所有http方法。

你可以通过php的cURL扩展访问任何REST API。但是，API文档(方法，参数等)必须由您的客户端提供!

例子:

// Method: POST, PUT, GET etc
// Data: array("param" => "value") ==> index.php?param=value

function CallAPI($method, $url, $data = false)
{
    $curl = curl_init();

    switch ($method)
    {
        case "POST":
            curl_setopt($curl, CURLOPT_POST, 1);

            if ($data)
                curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
            break;
        case "PUT":
            curl_setopt($curl, CURLOPT_PUT, 1);
            break;
        default:
            if ($data)
                $url = sprintf("%s?%s", $url, http_build_query($data));
    }

    // Optional Authentication:
    curl_setopt($curl, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
    curl_setopt($curl, CURLOPT_USERPWD, "username:password");

    curl_setopt($curl, CURLOPT_URL, $url);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);

    $result = curl_exec($curl);

    curl_close($curl);

    return $result;
}

使用狂饮。它是一个“PHP HTTP客户端，可以很容易地使用HTTP/1.1，并消除使用web服务的痛苦”。使用Guzzle比使用cURL要容易得多。

下面是来自该网站的一个例子:

$client = new GuzzleHttp\Client();
$res = $client->get('https://api.github.com/user', [
    'auth' =>  ['user', 'pass']
]);
echo $res->getStatusCode();           // 200
echo $res->getHeader('content-type'); // 'application/json; charset=utf8'
echo $res->getBody();                 // {"type":"User"...'
var_export($res->json());             // Outputs the JSON decoded data

实际上有很多客户。其中之一是佩斯，看看这个。请记住，这些REST调用是简单的http请求，具有各种方法:GET、POST、PUT和DELETE。

正如@Christoph Winkler提到的，这是实现它的基类:

curl_helper.php

// This class has all the necessary code for making API calls thru curl library

class CurlHelper {

// This method will perform an action/method thru HTTP/API calls
// Parameter description:
// Method= POST, PUT, GET etc
// Data= array("param" => "value") ==> index.php?param=value
public static function perform_http_request($method, $url, $data = false)
{
    $curl = curl_init();

    switch ($method)
    {
        case "POST":
            curl_setopt($curl, CURLOPT_POST, 1);

            if ($data)
                curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
            break;
        case "PUT":
            curl_setopt($curl, CURLOPT_PUT, 1);
            break;
        default:
            if ($data)
                $url = sprintf("%s?%s", $url, http_build_query($data));
    }

    // Optional Authentication:
    //curl_setopt($curl, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
    //curl_setopt($curl, CURLOPT_USERPWD, "username:password");

    curl_setopt($curl, CURLOPT_URL, $url);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);

    $result = curl_exec($curl);

    curl_close($curl);

    return $result;
}

}

然后你就可以包含这个文件并使用它，例如:any.php

    require_once("curl_helper.php");
    ...
    $action = "GET";
    $url = "api.server.com/model"
    echo "Trying to reach ...";
    echo $url;
    $parameters = array("param" => "value");
    $result = CurlHelper::perform_http_request($action, $url, $parameters);
    echo print_r($result)

如果你有一个url并且你的php支持它，你可以调用file_get_contents:

$response = file_get_contents('http://example.com/path/to/api/call?param1=5');

如果$response是JSON，使用json_decode将其转换为php数组:

$response = json_decode($response);

如果$response是XML，使用simple_xml类:

$response = new SimpleXMLElement($response);

http://sg2.php.net/manual/en/simplexml.examples-basic.php