> 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/environment/usage.md).

# Usage

For most application code, use the helpers.

## Reading an environment value

```php
$appName = env('APP_NAME', 'Quantum');
$dbHost = env('DB_HOST', '127.0.0.1');
```

This works only after the shared `Environment` instance has been loaded during bootstrap.

## Inspecting the active environment

```php
$environment = environment();

if ($environment->isProduction()) {
    // production-only behavior
}
```

You can also read the raw environment name with `getAppEnv()`.

## Updating a loaded environment file

```php
$environment = environment();
$environment->setMutable(true);
$environment->updateRow('APP_NAME', 'Quantum 3');
```

Use this carefully:

* mutability is off by default
* the target file must already have been selected and loaded
* updates modify the real `.env` file under `App::getBaseDir()`

## Reading request metadata

```php
$server = server();

$method = $server->method();
$uri = $server->uri();
$contentType = $server->contentType(true);
$ip = get_user_ip();
```

## Reading normalized headers

```php
$headers = server()->getAllHeaders();
$requestId = $headers['x-request-id'] ?? null;
```

Remember that the keys are normalized to lowercase hyphenated names.

## Recommended usage patterns

* treat `Environment` as bootstrap-loaded configuration state, not as a reloadable store
* use `env()` for reads and keep direct `Environment` mutation limited to tooling or controlled setup flows
* use `server()` when you want one shared request metadata object instead of touching `$_SERVER` directly
* be careful with `Server::ip()` behind proxies because it prefers client-supplied forwarding headers


---

# 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/environment/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.