> For the complete documentation index, see [llms.txt](https://quantumphp.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://quantumphp.gitbook.io/docs/packages/logger/usage.md).

# Usage

## Log to the configured default backend

For most application code, use the helper or resolve the default logger:

```php
error('Payment gateway timeout');

logger()->warning('Retrying webhook delivery');
```

Outside debug mode, these calls write only when the configured threshold allows them.

## Choose a file adapter explicitly

When you want to force one of the file backends in normal runtime, request it by name:

```php
use Quantum\Logger\Enums\LoggerType;

$dailyLogger = logger(LoggerType::DAILY);
$dailyLogger->error('Nightly sync failed');
```

This is useful when your config defines multiple logging backends and you want one intentionally.

## Send a stack trace to a file log

File adapters treat `trace` as a special context value:

```php
try {
    // ...
} catch (Throwable $exception) {
    logger()->error('Import job ended early', [
        'trace' => $exception->getTraceAsString(),
    ]);
}
```

That writes the formatted message first and then appends the trace block.

## Log a structured payload

When you want file logs to capture structured data, call the logger instance directly:

```php
logger()->info([
    'job' => 'catalog-sync',
    'status' => 'queued',
    'items' => 48,
]);
```

File adapters JSON-format array messages before writing them. The global level helpers accept string messages, so `logger()` is the better fit for this style.

## Route debug messages into a custom debugger tab

In debug mode, you can place a message in a specific DebugBar tab:

```php
logger()->info('SMTP transport ready', [
    'tab' => 'mails',
]);
```

If the debugger is disabled, the message adapter drops the message silently.

## Pick the right backend

### Use `single` when:

* you want one stable file such as `storage/logs/app.log`
* external tooling already tails or rotates one known file

### Use `daily` when:

* you want one log file per day
* you prefer date-based separation without external naming logic

### Rely on debug-mode `message` when:

* you are troubleshooting locally
* you want logs in DebugBar instead of on disk

## Practical caveats

* `logger(LoggerType::MESSAGE)` is valid only in debug mode.
* `logger(LoggerType::DAILY)` or `logger(LoggerType::SINGLE)` still resolves to `message` in debug mode.
* Reusing a resolved logger reuses the adapter instance behind it.
* Calling `log()` with a non-standard level string is not rejected by the package, but it can produce uneven behavior. Prefer the standard level methods instead.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://quantumphp.gitbook.io/docs/packages/logger/usage.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.