Nette HTTP Component

Introduction

HTTP request and response are encapsulated in Nette\Http\Request and Nette\Http\Response objects which offer comfortable API and also act as sanitization filter.

Documentation can be found on the website.

Support Me

Do you like Nette DI? Are you looking forward to the new features?

Thank you!

Installation

composer require nette/http

It requires PHP version 8.0 and supports PHP up to 8.3.

HTTP Request

An HTTP request is an Nette\Http\Request object. What is important is that Nette when creating this object, it clears all GET, POST and COOKIE input parameters as well as URLs of control characters and invalid UTF-8 sequences. So you can safely continue working with the data. The cleaned data is then used in presenters and forms.

Class Request is immutable. It has no setters, it has only one so-called wither withUrl(), which does not change the object, but returns a new instance with a modified value.

withUrl(Nette\Http\UrlScript $url): Nette\Http\Request

Returns a clone with a different URL.

getUrl(): Nette\Http\UrlScript

Returns the URL of the request as object [UrlScript|urls#UrlScript].

$url = $httpRequest->getUrl();
echo $url; // https://nette.org/en/documentation?action=edit
echo $url->getHost(); // nette.org

Browsers do not send a fragment to the server, so $url->getFragment() will return an empty string.

getQuery(string $key = null): string|array|null

Returns GET request parameters:

$all = $httpRequest->getQuery();    // array of all URL parameters
$id = $httpRequest->getQuery('id'); // returns GET parameter 'id' (or null)

getPost(string $key = null): string|array|null

Returns POST request parameters:

$all = $httpRequest->getPost();     // array of all POST parameters
$id = $httpRequest->getPost('id');  // returns POST parameter 'id' (or null)

getFile(string $key): Nette\Http\FileUpload|array|null

Returns upload as object Nette\Http\FileUpload:

$file = $httpRequest->getFile('avatar');
if ($file->hasFile()) { // was any file uploaded?
	$file->getName(); // name of the file sent by user
	$file->getSanitizedName(); // the name without dangerous characters
}

getFiles(): array

Returns tree of upload files in a normalized structure, with each leaf an instance of Nette\Http\FileUpload:

$files = $httpRequest->getFiles();

getCookie(string $key): string|array|null

Returns a cookie or null if it does not exist.

$sessId = $httpRequest->getCookie('sess_id');

getCookies(): array

Returns all cookies:

$cookies = $httpRequest->getCookies();

getMethod(): string

Returns the HTTP method with which the request was made.

echo $httpRequest->getMethod(); // GET, POST, HEAD, PUT

isMethod(string $method): bool

Checks the HTTP method with which the request was made. The parameter is case-insensitive.

if ($httpRequest->isMethod('GET')) ...

getHeader(string $header): ?string

Returns an HTTP header or null if it does not exist. The parameter is case-insensitive:

$userAgent = $httpRequest->getHeader('User-Agent');

getHeaders(): array

Returns all HTTP headers as associative array:

$headers = $httpRequest->getHeaders();
echo $headers['Content-Type'];

getReferer(): ?Nette\Http\UrlImmutable

What URL did the user come from? Beware, it is not reliable at all.

isSecured(): bool

Is the connection encrypted (HTTPS)? You may need to [set up a proxy|configuring#HTTP proxy] for proper functionality.

isSameSite(): bool

Is the request coming from the same (sub) domain and is initiated by clicking on a link?

isAjax(): bool

Is it an AJAX request?

getRemoteAddress(): ?string

Returns the user's IP address. You may need to [set up a proxy|configuring#HTTP proxy] for proper functionality.

getRemoteHost(): ?string

Returns DNS translation of the user's IP address. You may need to [set up a proxy|configuring#HTTP proxy] for proper functionality.

getRawBody(): ?string

Returns the body of the HTTP request:

$body = $httpRequest->getRawBody();

detectLanguage(array $langs): ?string

Detects language. As a parameter $lang, we pass an array of languages ​​that the application supports, and it returns the one preferred by browser. It is not magic, the method just uses the Accept-Language header. If no match is reached, it returns null.

// Header sent by browser: Accept-Language: cs,en-us;q=0.8,en;q=0.5,sl;q=0.3

$langs = ['hu', 'pl', 'en']; // languages supported in application
echo $httpRequest->detectLanguage($langs); // en

RequestFactory

The object of the current HTTP request is created by Nette\Http\RequestFactory. If you are writing an application that does not use a DI container, you create a request as follows:

$factory = new Nette\Http\RequestFactory;
$httpRequest = $factory->fromGlobals();

RequestFactory can be configured before calling fromGlobals(). We can disable all sanitization of input parameters from invalid UTF-8 sequences using $factory->setBinary(). And also set up a proxy server, which is important for the correct detection of the user's IP address using $factory->setProxy(...).

It's possible to clean up URLs from characters that can get into them because of poorly implemented comment systems on various other websites by using filters:

// remove spaces from path
$requestFactory->urlFilters['path']['%20'] = '';

// remove dot, comma or right parenthesis form the end of the URL
$requestFactory->urlFilters['url']['[.,)]$'] = '';

// clean the path from duplicated slashes (default filter)
$requestFactory->urlFilters['path']['/{2,}'] = '/';

HTTP Response

An HTTP response is an Nette\Http\Response object. Unlike the Request, the object is mutable, so you can use setters to change the state, ie to send headers. Remember that all setters must be called before any actual output is sent. The isSent() method tells if output have been sent. If it returns true, each attempt to send a header throws an Nette\InvalidStateException exception.

setCode(int $code, string $reason = null)

Changes a status response code. For better source code readability it is recommended to use predefined constants instead of actual numbers.

$httpResponse->setCode(Nette\Http\Response::S404_NotFound);

getCode(): int

Returns the status code of the response.

isSent(): bool

Returns whether headers have already been sent from the server to the browser, so it is no longer possible to send headers or change the status code.

setHeader(string $name, string $value)

Sends an HTTP header and overwrites previously sent header of the same name.

$httpResponse->setHeader('Pragma', 'no-cache');

addHeader(string $name, string $value)

Sends an HTTP header and doesn't overwrite previously sent header of the same name.

$httpResponse->addHeader('Accept', 'application/json');
$httpResponse->addHeader('Accept', 'application/xml');

deleteHeader(string $name)

Deletes a previously sent HTTP header.

getHeader(string $header): ?string

Returns the sent HTTP header, or null if it does not exist. The parameter is case-insensitive.

$pragma = $httpResponse->getHeader('Pragma');

getHeaders(): array

Returns all sent HTTP headers as associative array.

$headers = $httpResponse->getHeaders();
echo $headers['Pragma'];

setContentType(string $type, string $charset = null)

Sends the header Content-Type.

$httpResponse->setContentType('text/plain', 'UTF-8');

redirect(string $url, int $code = self::S302_FOUND): void

Redirects to another URL. Don't forget to quit the script then.

$httpResponse->redirect('http://example.com');
exit;

setExpiration(?string $time)

Sets the expiration of the HTTP document using the Cache-Control and Expires headers. The parameter is either a time interval (as text) or null, which disables caching.

// browser cache expires in one hour
$httpResponse->setExpiration('1 hour');

setCookie(string $name, string $value, $time, string $path = null, string $domain = null, bool $secure = null, bool $httpOnly = null, string $sameSite = null)

Sends a cookie. The default values ​​of the parameters are:

• $path with scope to all directories ('/')
• $domain with scope of the current (sub)domain, but not its subdomains
• $secure defaults to false
• $httpOnly is true, so the cookie is inaccessible to JavaScript
• $sameSite is null, so the flag is not specified

The time can be specified as a string or the number of seconds.

$httpResponse->setCookie('lang', 'en', '100 days');

deleteCookie(string $name, string $path = null, string $domain = null, bool $secure = null): void

Deletes a cookie. The default values ​​of the parameters are:

• $path with scope to all directories ('/')
• $domain with scope of the current (sub)domain, but not its subdomains
• $secure defaults to false

$httpResponse->deleteCookie('lang');

Uploaded Files

Method Nette\Http\Request::getFiles() return a tree of upload files in a normalized structure, with each leaf an instance of Nette\Http\FileUpload. These objects encapsulate the data submitted by the <input type=file> form element.

The structure reflects the naming of elements in HTML. In the simplest example, this might be a single named form element submitted as:

<input type="file" name="avatar">

In this case, the $request->getFiles() returns array:

[
	'avatar' => /* FileUpload instance */
]

The FileUpload object is created even if the user did not upload any file or the upload failed. Method hasFile() returns true if a file has been sent:

$request->getFile('avatar')->hasFile();

In the case of an input using array notation for the name:

<input type="file" name="my-form[details][avatar]">

returned tree ends up looking like this:

[
	'my-form' => [
		'details' => [
			'avatar' => /* FileUpload instance */
		],
	],
]

You can also create arrays of files:

<input type="file" name="my-form[details][avatars][] multiple">

In such a case structure looks like:

[
	'my-form' => [
		'details' => [
			'avatars' => [
				0 => /* FileUpload instance */,
				1 => /* FileUpload instance */,
				2 => /* FileUpload instance */,
			],
		],
	],
]

The best way to access index 1 of a nested array is as follows:

$file = Nette\Utils\Arrays::get(
	$request->getFiles(),
	['my-form', 'details', 'avatars', 1],
	null
);
if ($file instanceof FileUpload) {
	...
}

Because you can't trust data from the outside and therefore don't rely on the form of the file structure, it's safer to use the Arrays::get() than the $request->getFiles()['my-form']['details']['avatars'][1], which may fail.

Overview of FileUpload Methods .{toc: FileUpload}

hasFile(): bool

Returns true if the user has uploaded a file.

isOk(): bool

Returns true if the file was uploaded successfully.

getError(): int

Returns the error code associated with the uploaded file. It is be one of UPLOAD_ERR_XXX constants. If the file was uploaded successfully, it returns UPLOAD_ERR_OK.

move(string $dest)

Moves an uploaded file to a new location. If the destination file already exists, it will be overwritten.

$file->move('/path/to/files/name.ext');

getContents(): ?string

Returns the contents of the uploaded file. If the upload was not successful, it returns null.

getContentType(): ?string

Detects the MIME content type of the uploaded file based on its signature. If the upload was not successful or the detection failed, it returns null.

Requires PHP extension fileinfo.

getName(): string

Returns the original file name as submitted by the browser.

Do not trust the value returned by this method. A client could send a malicious filename with the intention to corrupt or hack your application.

getSanitizedName(): string

Returns the sanitized file name. It contains only ASCII characters [a-zA-Z0-9.-]. If the name does not contain such characters, it returns 'unknown'. If the file is JPEG, PNG, GIF, or WebP image, it returns the correct file extension.

getSize(): int

Returns the size of the uploaded file. If the upload was not successful, it returns 0.

getTemporaryFile(): string

Returns the path of the temporary location of the uploaded file. If the upload was not successful, it returns ''.

isImage(): bool

Returns true if the uploaded file is a JPEG, PNG, GIF, or WebP image. Detection is based on its signature. The integrity of the entire file is not checked. You can find out if an image is not corrupted for example by trying to load it.

Requires PHP extension fileinfo.

getImageSize(): ?array

Returns a pair of [width, height] with dimensions of the uploaded image. If the upload was not successful or is not a valid image, it returns null.

toImage(): Nette\Utils\Image

Loads an image as an Image object. If the upload was not successful or is not a valid image, it throws an Nette\Utils\ImageException exception.

Sessions

When using sessions, each user receives a unique identifier called session ID, which is passed in a cookie. This serves as the key to the session data. Unlike cookies, which are stored on the browser side, session data is stored on the server side.

The session is managed by the Nette\Http\Session object.

Starting Session

By default, Nette automatically starts a session if the HTTP request contains a cookie with a session ID. It also starts automatically when we start reading from or writing data to it. Manually is session started by $session->start().

PHP sends HTTP headers affecting caching when starting the session, see session_cache_limiter, and possibly a cookie with the session ID. Therefore, it is always necessary to start the session before sending any output to the browser, otherwise an exception will be thrown. So if you know that a session will be used during page rendering, start it manually before, for example in the presenter.

In developer mode, Tracy starts the session because it uses it to display redirection and AJAX requests bars in the Tracy Bar.

Section

In pure PHP, the session data store is implemented as an array accessible via a global variable $_SESSION. The problem is that applications normally consist of a number of independent parts, and if all have only one same array available, sooner or later a name collision will occur.

Nette Framework solves the problem by dividing the entire space into sections (objects Nette\Http\SessionSection). Each unit then uses its own section with a unique name and no collisions can occur.

We get the section from the session manager:

$section = $session->getSession('unique name');

In the presenter it is enough to call getSession() with the parameter:

// $this is Presenter
$section = $this->getSession('unique name');

The existence of the section can be checked by the method $session->hasSection('unique name').

And then it's really simple to work with that section:

// variable writing
$section->userName = 'john'; // nebo $section['userName'] = 'john';

// variable reading
echo $section->userName; // nebo echo $section['userName'];

// variable removing
unset($section->userName);  // unset($section['userName']);

It's possible to use foreach cycle to obtain all variables from section:

foreach ($section as $key => $val) {
	echo "$key = $val";
}

Accessing a non-existent variable does not generate any error (the returned value is null). It could be undesirable behavior in some cases and that's why there is a possibility to change it:

$section->warnOnUndefined = true;

How to Set Expiration

Expiration can be set for individual sections or even individual variables. We can let the user's login expire in 20 minutes, but still remember the contents of a shopping cart.

// section will expire after 20 minutes
$section->setExpiration('20 minutes');

// variable $section->flash will expire after 30 seconds
$section->setExpiration('30 seconds', 'flash');

The cancellation of the previously set expiration can be achieved by the method removeExpiration(). Immediate deletion of the whole section will be ensured by the method remove().

Session Management

Overview of methods of the Nette\Http\Session class for session management:

start(): void

Starts a session.

isStarted(): bool

Is the session started?

close(): void

Ends the session. The session ends automatically at the end of the script.

destroy(): void

Ends and deletes the session.

exists(): bool

Does the HTTP request contain a cookie with a session ID?

regenerateId(): void

Generates a new random session ID. Data remain unchanged.

getId(): string

Returns the session ID.

Configuration

Methods must be called before starting a session.

setName(string $name): static

Changes the session name. It is possible to run several different sessions at the same time within one website, each under a different name.

getName(): string

Returns the session name.

setOptions(array $options): static

Configures the session. It is possible to set all PHP session directives (in camelCase format, eg write savePath instead of session.save_path) and also readAndClose.

setExpiration(?string $time): static

Sets the time of inactivity after which the session expires.

setCookieParameters(string $path, string $domain = null, bool $secure = null, string $samesite = null): static

Sets parameters for cookies.

setSavePath(string $path): static

Sets the directory where session files are stored.

setHandler(\SessionHandlerInterface $handler): static

Sets custom handler, see PHP documentation.

Safety First

The server assumes that it communicates with the same user as long as requests contain the same session ID. The task of security mechanisms is to ensure that this behavior really works and that there is no possibility to substitute or steal an identifier.

That's why Nette Framework properly configures PHP directives to transfer session ID only in cookies, to avoid access from JavaScript and to ignore the identifiers in the URL. Moreover in critical moments, such as user login, it generates a new Session ID.

Function ini_set is used for configuring PHP, but unfortunately, its use is prohibited at some web hosting services. If it's your case, try to ask your hosting provider to allow this function for you, or at least to configure his server properly. .[note]

Url

The Nette\Http\Url class makes it easy to work with the URL and its individual components, which are outlined in this diagram:

 scheme  user  password  host   port    path        query  fragment
   |      |      |        |      |       |            |       |
 /--\   /--\ /------\ /-------\ /--\/----------\ /--------\ /----\
 http://john:xyz%[email protected]:8080/en/download?name=param#footer
 \______\__________________________/
     |               |
  hostUrl        authority

URL generation is intuitive:

use Nette\Http\Url;

$url = new Url;
$url->setScheme('https')
	->setHost('localhost')
	->setPath('/edit')
	->setQueryParameter('foo', 'bar');

echo $url; // 'https://localhost/edit?foo=bar'

You can also parse the URL and then manipulate it:

$url = new Url(
	'http://john:xyz%[email protected]:8080/en/download?name=param#footer'
);

The following methods are available to get or change individual URL components:

We can also operate with individual query parameters using:

Method getDomain(int $level = 2) returns the right or left part of the host. This is how it works if the host is www.nette.org:

The Url class implements the JsonSerializable interface and has a __toString() method so that the object can be printed or used in data passed to json_encode().

echo $url;
echo json_encode([$url]);

Method isEqual(string|Url $anotherUrl): bool tests whether the two URLs are identical.

$url->isEqual('https://nette.org');

UrlImmutable

The class Nette\Http\UrlImmutable is an immutable alternative to class Url (just as in PHP DateTimeImmutable is immutable alternative to DateTime). Instead of setters, it has so-called withers, which do not change the object, but return new instances with a modified value:

use Nette\Http\UrlImmutable;

$url = new UrlImmutable(
	'http://john:xyz%[email protected]:8080/en/download?name=param#footer'
);

$newUrl = $url
	->withUser('')
	->withPassword('')
	->withPath('/cs/');

echo $newUrl; // 'http://nette.org:8080/cs/?name=param#footer'

The following methods are available to get or change individual URL components:

We can also operate with individual query parameters using:

The getDomain(int $level = 2) method works the same as the method in Url. Method withoutUserInfo() removes user and password.

The UrlImmutable class implements the JsonSerializable interface and has a __toString() method so that the object can be printed or used in data passed to json_encode().

echo $url;
echo json_encode([$url]);

Method isEqual(string|Url $anotherUrl): bool tests whether the two URLs are identical.

If you like Nette, please make a donation now. Thank you!