HTTP Client¶
Overview¶
Zend\Http\Client
provides an easy interface for performing Hyper-Text Transfer Protocol (HTTP) requests.
Zend\Http\Client
supports the most simple features expected from an HTTP client, as well as some more complex
features such as HTTP authentication and file uploads. Successful requests (and most unsuccessful ones too)
return a Zend\Http\Response
object, which provides access to the response’s headers and body (see this
section).
Quick Start¶
The class constructor optionally accepts a URL as its first parameter (can be either a string or a
Zend\Uri\Http
object), and an array or Zend\Config\Config
object containing configuration options.
The send()
method is used to submit the request to the remote server, and a Zend\Http\Response
object is
returned:
1 2 3 4 5 6 7 | use Zend\Http\Client;
$client = new Client('http://example.org', array(
'maxredirects' => 0,
'timeout' => 30
));
$response = $client->send();
|
Both constructor parameters can be left out, and set later using the setUri() and setConfig() methods:
1 2 3 4 5 6 7 8 9 | use Zend\Http\Client;
$client = new Client();
$client->setUri('http://example.org');
$client->setOptions(array(
'maxredirects' => 0,
'timeout' => 30
));
$response = $client->send();
|
Zend\Http\Client
can also dispatch requests using a separately configured request
object (see the
Zend\Http\Request manual page for full details of the methods available):
1 2 3 4 5 6 7 8 9 | use Zend\Http\Client;
use Zend\Http\Request;
$request = new Request();
$request->setUri('http://example.org');
$client = new Client();
$response = $client->send($request);
|
Note
Zend\Http\Client
uses Zend\Uri\Http
to validate URLs. See the Zend\Uri manual page
for more information on the validation process.
Configuration¶
The constructor and setOptions() method accepts an associative array of configuration parameters, or a
Zend\Config\Config
object. Setting these parameters is optional, as they all have default values.
Zend\Http\Client configuration parameters¶ Parameter Description Expected Values Default Value maxredirects Maximum number of redirections to follow (0 = none) integer 5 strictredirects Whether to strictly follow the RFC when redirecting (see this section) boolean FALSE useragent User agent identifier string (sent in request headers) string ‘Zend\Http\Client’ timeout Connection timeout (seconds) integer 10 httpversion HTTP protocol version (usually ‘1.1’ or ‘1.0’) string ‘1.1’ adapter Connection adapter class to use (see this section) mixed ‘Zend\Http\Client\Adapter\Socket’ keepalive Whether to enable keep-alive connections with the server. Useful and might improve performance if several consecutive requests to the same server are performed. boolean FALSE storeresponse Whether to store last response for later retrieval with getLastResponse(). If set to FALSE, getLastResponse() will return NULL. boolean TRUE encodecookies Whether to pass the cookie value through urlencode/urldecode. Enabling this breaks support with some web servers. Disabling this limits the range of values the cookies can contain. boolean TRUE outputstream Destination for streaming of received data (options: string (filename), true for temp file, false/null to disable streaming) boolean FALSE rfc3986strict Whether to strictly adhere to RFC 3986 (in practice, this means replacing ‘+’ with ‘%20’) boolean FALSE
The options are also passed to the adapter class upon instantiation, so the same array or Zend\Config\Config
object) can be used for adapter configuration. See the
Zend Http Client adapter section for more information on the
adapter-specific options available.
Examples¶
Performing a Simple GET Request¶
Performing simple HTTP requests is very easily done:
1 2 3 4 | use Zend\Http\Client;
$client = new Client('http://example.org');
$response = $client->send();
|
Using Request Methods Other Than GET¶
The request method can be set using setMethod()
. If no method is specified, the method set by the last
setMethod()
call is used. If setMethod()
was never called, the default request method is GET
.
1 2 3 4 5 6 7 | use Zend\Http\Client;
$client = new Client('http://example.org');
// Performing a POST request
$client->setMethod('POST');
$response = $client->send();
|
For convenience, Zend\Http\Request
defines all the request methods as class constants, Zend\Http\Request::METHOD_GET
,
Zend\Http\Request::METHOD_POST
and so on:
1 2 3 4 5 6 7 8 | use Zend\Http\Client;
use Zend\Http\Request;
$client = new Client('http://example.org');
// Performing a POST request
$client->setMethod(Request::METHOD_POST);
$response = $client->send();
|
Setting GET parameters¶
Adding GET
parameters to an HTTP request is quite simple, and can be done either by specifying them as part
of the URL, or by using the setParameterGet()
method. This method takes the GET
parameters as an
associative array of name => value GET
variables.
1 2 3 4 5 6 7 8 9 10 11 12 13 | use Zend\Http\Client;
$client = new Client();
// This is equivalent to setting a URL in the Client's constructor:
$client->setUri('http://example.com/index.php?knight=lancelot');
// Adding several parameters with one call
$client->setParameterGet(array(
'first_name' => 'Bender',
'middle_name' => 'Bending',
'last_name' => 'Rodríguez',
'made_in' => 'Mexico',
));
|
Setting POST Parameters¶
While GET
parameters can be sent with every request method, POST
parameters are only sent in the body of
POST
requests. Adding POST
parameters to a request is very similar to adding GET
parameters, and can be
done with the setParameterPost()
method, which is identical to the setParameterGet()
method in structure.
1 2 3 4 5 6 7 8 9 10 | use Zend\Http\Client;
$client = new Client();
// Setting several POST parameters, one of them with several values
$client->setParameterPost(array(
'language' => 'es',
'country' => 'ar',
'selection' => array(45, 32, 80)
));
|
Note that when sending POST
requests, you can set both GET
and POST
parameters. On the other hand,
setting POST parameters on a non-POST
request will not trigger an error, rendering it useless. Unless the
request is a POST
request, POST
parameters are simply ignored.
Connecting to SSL URLs¶
If you are trying to connect to an SSL (https) URL and are using the default (Zend\Http\Client\Adapter\Socket
)
adapter, you may need to set the sslcapath
configuration option in order to allow PHP to validate the
SSL certificate:
1 2 3 4 5 6 | use Zend\Http\Client;
$client = new Client('https://example.org', array(
'sslcapath' => '/etc/ssl/certs'
));
$response = $client->send();
|
The exact path to use will vary depending on your Operating System. Without this you’ll get the exception “Unable to enable crypto on TCP connection” when trying to connect.
Alternatively, you could switch to the curl adapter, which negotiates SSL connections more transparently:
1 2 3 4 5 6 | use Zend\Http\Client;
$client = new Client('https://example.org', array(
'adapter' => 'Zend\Http\Client\Adapter\Curl'
));
$response = $client->send();
|
A Complete Example¶
1 2 3 4 5 6 7 8 9 10 11 12 13 14 | use Zend\Http\Client;
$client = new Client();
$client->setUri('http://www.example.com');
$client->setMethod('POST');
$client->setParameterPost(array(
'foo' => 'bar'
));
$response = $client->send();
if ($response->isSuccess()) {
// the POST was successful
}
|
or the same thing, using a request object:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 | use Zend\Http\Client;
use Zend\Http\Request;
$request = new Request();
$request->setUri('http://www.example.com');
$request->setMethod('POST');
$request->getPost()->set('foo', 'bar');
$client = new Client();
$response = $client->send($request);
if ($response->isSuccess()) {
// the POST was successful
}
|
[1] | See RFC 2616 -http://www.w3.org/Protocols/rfc2616/rfc2616.html. |