Slim3.0 手册 [ 英 ]
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The Request

Request

Request HelpersDetect XHR requestsContent TypeMedia TypeCharacter SetContent LengthIP Address

Your Slim app’s routes and middleware are given a PSR 7 request object that represents the current HTTP request received by your web server. The request object implements the PSR 7 ServerRequestInterface with which you can inspect and manipulate the HTTP request method, headers, and body.

How to get the Request object

The PSR 7 request object is injected into your Slim application routes as the first argument to the route callback like this:

<?php
use PsrHttpMessageServerRequestInterface;
use PsrHttpMessageResponseInterface;

$app = new SlimApp;
$app->get("/foo", function (ServerRequestInterface $request, ResponseInterface $response) {
    // Use the PSR 7 $request object

    return $response;
});
$app->run();

Figure 1: Inject PSR 7 request into application route callback.

The PSR 7 request object is injected into your Slim application middleware as the first argument of the middleware callable like this:

<?php
use PsrHttpMessageServerRequestInterface;
use PsrHttpMessageResponseInterface;

$app = new SlimApp;
$app->add(function (ServerRequestInterface $request, ResponseInterface $response, callable $next) {
    // Use the PSR 7 $request object

    return $next($request, $response);
});
// Define app routes...
$app->run();

Figure 2: Inject PSR 7 request into application middleware.

The Request Method

Every HTTP request has a method that is typically one of:

  • GET
  • POST
  • PUT
  • DELETE
  • HEAD
  • PATCH
  • OPTIONS

You can inspect the HTTP request’s method with the Request object method appropriately named getMethod().

$method = $request->getMethod();

Because this is a common task, Slim’s built-in PSR 7 implementation also provides these proprietary methods that return true or false.

  • $request->isGet()
  • $request->isPost()
  • $request->isPut()
  • $request->isDelete()
  • $request->isHead()
  • $request->isPatch()
  • $request->isOptions()

It is possible to fake or override the HTTP request method. This is useful if, for example, you need to mimic a PUT request using a traditional web browser that only supports GET or POSTrequests.

There are two ways to override the HTTP request method. You can include a _METHODparameter in a POST request’s body. The HTTP request must use the application/x-www-form-urlencoded content type.

POST /path HTTP/1.1
Host: example.com
Content-type: application/x-www-form-urlencoded
Content-length: 22

data=value&_METHOD=PUT

Figure 3: Override HTTP method with _METHOD parameter.

You can also override the HTTP request method with a custom X-Http-Method-OverrideHTTP request header. This works with any HTTP request content type.

POST /path HTTP/1.1
Host: example.com
Content-type: application/json
Content-length: 16
X-Http-Method-Override: PUT

{"data":"value"}

Figure 4: Override HTTP method with X-Http-Method-Override header.

You can fetch the original (non-overridden) HTTP method with the PSR 7 Request object’s method named getOriginalMethod().

The Request URI

Every HTTP request has a URI that identifies the requested application resource. The HTTP request URI has several parts:

  • Scheme (e.g. http or https)
  • Host (e.g. example.com)
  • Port (e.g. 80 or 443)
  • Path (e.g. /users/1)
  • Query string (e.g. sort=created&dir=asc)

You can fetch the PSR 7 Request object’s URI with its getUri() method:

$uri = $request->getUri();

The PSR 7 Request object’s URI is itself an object that provides the following methods to inspect the HTTP request’s URL parts:

  • getScheme()
  • getHost()
  • getPort()
  • getPath()
  • getBasePath()
  • getQuery() (returns string)
  • getQueryParams() (returns associative array)

Base Path

If your Slim application"s front-controller lives in a physical subdirectory beneath your document root directory, you can fetch the HTTP request"s physical base path (relative to the document root) with the Uri object"s getBasePath() method. This will be an empty string if the Slim application is installed in the document root"s top-most directory.

The Request Headers

Every HTTP request has headers. These are metadata that describe the HTTP request but are not visible in the request’s body. Slim’s PSR 7 Request object provides several methods to inspect its headers.

Get All Headers

You can fetch all HTTP request headers as an associative array with the PSR 7 Request object’s getHeaders() method. The resultant associative array’s keys are the header names and its values are themselves a numeric array of string values for their respective header name.

$headers = $request->getHeaders();
foreach ($headers as $name => $values) {
    echo $name . ": " . implode(", ", $values);
}

Figure 5: Fetch and iterate all HTTP request headers as an associative array.

Get One Header

You can get a single header’s value(s) with the PSR 7 Request object’s getHeader($name)method. This returns an array of values for the given header name. Remember, a single HTTP header may have more than one value!

$headerValueArray = $request->getHeader("Accept");

Figure 6: Get values for a specific HTTP header.

You may also fetch a comma-separated string with all values for a given header with the PSR 7 Request object’s getHeaderLine($name) method. Unlike the getHeader($name) method, this method returns a comma-separated string.

$headerValueString = $request->getHeaderLine("Accept");

Figure 7: Get single header"s values as comma-separated string.

Detect Header

You can test for the presence of a header with the PSR 7 Request object’s hasHeader($name)method.

if ($request->hasHeader("Accept")) {
    // Do something
}

Figure 8: Detect presence of a specific HTTP request header.

The Request Body

Every HTTP request has a body. If you are building a Slim application that consumes JSON or XML data, you can use the PSR 7 Request object’s getParsedBody() method to parse the HTTP request body into a native PHP format. Slim can parse JSON, XML, and URL-encoded data out of the box.

$parsedBody = $request->getParsedBody();

Figure 9: Parse HTTP request body into native PHP format

  • JSON requests are converted into a PHP object with json_decode($input).
  • XML requests are converted into a SimpleXMLElement withsimplexml_load_string($input).
  • URL-encoded requests are converted into a PHP array with parse_str($input).

Technically speaking, Slim’s PSR 7 Request object represents the HTTP request body as an instance of PsrHttpMessageStreamInterface. You can get the HTTP request bodyStreamInterface instance with the PSR 7 Request object’s getBody() method. ThegetBody() method is preferable if the incoming HTTP request size is unknown or too large for available memory.

$body = $request->getBody();

Figure 10: Get HTTP request body

The resultant PsrHttpMessageStreamInterface instance provides the following methods to read and iterate its underlying PHP resource.

  • getSize()
  • tell()
  • eof()
  • isSeekable()
  • seek()
  • rewind()
  • isWritable()
  • write($string)
  • isReadable()
  • read($length)
  • getContents()
  • getMetadata($key = null)

Request Helpers

Slim’s PSR 7 Request implementation provides these additional proprietary methods to help you further inspect the HTTP request.

Detect XHR requests

You can detect XHR requests with the Request object’s isXhr() method. This method detects the presence of the X-Requested-With HTTP request header and ensures its value isXMLHttpRequest.

POST /path HTTP/1.1
Host: example.com
Content-type: application/x-www-form-urlencoded
Content-length: 7
X-Requested-With: XMLHttpRequest

foo=bar

Figure 11: Example XHR request.

if ($request->isXhr()) {
    // Do something
}

Content Type

You can fetch the HTTP request content type with the Request object’s getContentType()method. This returns the Content-Type header’s full value as provided by the HTTP client.

$contentType = $request->getContentType();

Media Type

You may not want the complete Content-Type header. What if, instead, you only want the media type? You can fetch the HTTP request media type with the Request object’sgetMediaType() method.

$mediaType = $request->getMediaType();

You can fetch the appended media type parameters as an associative array with the Request object’s getMediaTypeParams() method.

$mediaParams = $request->getMediaTypeParams();

Character Set

One of the most common media type parameters is the HTTP request character set. The Request object provides a dedicated method to retrieve this media type parameter.

$charset = $request->getContentCharset();

Content Length

You can fetch the HTTP request content length with the Request object’s getContentLength()method.

$length = $request->getContentLength();

IP Address

You can fetch the HTTP request’s source IP address with the Request object’s getIp()method. This method respects the X-Forwarded-For header, if present.

$ip = $request->getIp();
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