Context

• Introduction
• Interacting with Context
  • Get Context
  • Set Context
  • Check If Context Key Exists
  • Override Context
  • Destroy Context
  • Get or Set Context
  • Copy Context

Introduction

Context is an important feature in Laravel Hyperf, it is used to store the states with coroutines. Context in different coroutines are isolated, and when the coroutine terminates, the context will be destroyed. You don't need to worry about memory leakage without destroying the context manually.

Important

Do not mutate static variables in coroutines, because static variables are shared by all coroutines. It will cause states pollution and unpredictable bugs.

Interacting with Context

Get Context

The get method will return the value of the key, if not exists, it will return the default value.

use Hyperf\Context\Context;

$foo = Context::get('foo', 'bar');

$foo = Context::get('foo', 'bar', $coroutineId);

Set Context

The set method will set the value of the key, and return the value of the key.

use Hyperf\Context\Context;

// $foo is bar
$foo = Context::set('foo', 'bar');

$foo = Context::set('foo', 'bar', $coroutineId);

Check If Context Key Exists

The has method will return true if the key exists, otherwise false.

use Hyperf\Context\Context;

$exists = Context::has('foo');

$exists = Context::has('foo', $coroutineId);

Override Context

Sometimes we need to check if a specific key exists. If the key exists, override the value of a key in the context. You may do so using the override method.

use Hyperf\Context\Context;

$request = Context::override(ServerRequestInterface::class, function (ServerRequestInterface $request) {
    return $request->withAddedHeader('foo', 'bar');
});

Note

You can pass coroutineId to the third parameter to override the context in a specific coroutine.

Destroy Context

The destroy method will delete the value of the key in coroutine context.

use Hyperf\Context\Context;

Context::destroy('foo');

Context::destroy('foo', $coroutineId);

Get or Set Context

The getOrSet method will return the value of the key, if not exists, it will set the value of the key and return.

use Hyperf\Context\Context;

$foo = Context::getOrSet('foo', 'bar');

$foo = Context::getOrSet('foo', 'bar', $coroutineId);

Copy Context

The copy method will copy the context from another coroutine to the current coroutine.

use Hyperf\Context\Context;

Context::copy('foo', $fromCoroutineId, $onlyKeys);