open-telemetry / context
Context implementation for OpenTelemetry PHP.
Requires
- php: ^7.4 || ^8.0
- symfony/polyfill-php80: ^1.26
- symfony/polyfill-php81: ^1.26
- symfony/polyfill-php82: ^1.26
Suggests
- ext-ffi: To allow context switching in Fibers
This package is auto-updated.
Last update: 2024-06-29 06:00:52 UTC
README
OpenTelemetry Context
Immutable execution scoped propagation mechanism, for further details see opentelemetry-specification.
Installation
composer require open-telemetry/context
Usage
Implicit propagation
$context = Context::getCurrent(); // modify context $scope = $context->activate(); try { // run within new context } finally { $scope->detach(); }
It is recommended to use a try-finally statement after ::activate() to ensure that the created scope is properly ::detach()ed.
Debug scopes
By default, scopes created by ::activate() warn on invalid and missing calls to ::detach() in non-production
environments. This feature can be disabled by setting the environment variable OTEL_PHP_DEBUG_SCOPES_DISABLED to a
truthy value. Disabling is only recommended for applications using exit / die to prevent unavoidable notices.
Async applications
Fiber support - automatic context propagation to newly created fibers
Requires an NTS build, ext-ffi, and setting the environment variable OTEL_PHP_FIBERS_ENABLED to a truthy value. Additionally vendor/autoload.php has to be preloaded for non-CLI SAPIs if ffi.enable is set to preload.
Event loops
Event loops have to restore the original context on callback execution. A basic implementation could look like the following, though implementations should avoid keeping unnecessary references to arguments if possible:
function bindContext(Closure $closure): Closure { $context = Context::getCurrent(); return static function (mixed ...$args) use ($closure, $context): mixed { $scope = $context->activate(); try { return $closure(...$args); } finally { $scope->detach(); } }; }
Contributing
This repository is a read-only git subtree split. To contribute, please see the main OpenTelemetry PHP monorepo.