# Environment Variables { #environment-variables }

/// tip

If you already know what "environment variables" are and how to use them, feel free to skip this.

///

An environment variable (also known as "**env var**") is a variable that lives **outside** of the Python code, in the **operating system**, and could be read by your Python code (or by other programs as well).

To understand environment variables you can read [Environment Variables](../environment-variables.md){.internal-link target=_blank}.

///

## Types and validation { #types-and-validation }

These environment variables can only handle text strings, as they are external to Python and have to be compatible with other programs and the rest of the system (and even with different operating systems, as Linux, Windows, macOS).

   *
   * @param formal The type whose type variables or itself is mapped to other type(s). It's almost
   *     always a bug if {@code formal} isn't a type variable and contains no type variable. Make
   *     sure you are passing the two parameters in the right order.
   * @param actual The type that the formal type variable(s) are mapped to. It can be or contain yet

   *
   * @param formal The type whose type variables or itself is mapped to other type(s). It's almost
   *     always a bug if {@code formal} isn't a type variable and contains no type variable. Make
   *     sure you are passing the two parameters in the right order.
   * @param actual The type that the formal type variable(s) are mapped to. It can be or contain yet

# Conditional OpenAPI { #conditional-openapi }

If you needed to, you could use settings and environment variables to configure OpenAPI conditionally depending on the environment, and even disable it entirely.

## About security, APIs, and docs { #about-security-apis-and-docs }

Hiding your documentation user interfaces in production *shouldn't* be the way to protect your API.

		}
	}
	return m
}

func initConsoleServer() (*consoleapi.Server, error) {
	// unset all console_ environment variables.
	for _, cenv := range env.List(consolePrefix) {
		os.Unsetenv(cenv)
	}

	// enable all console environment variables
	minioConfigToConsoleFeatures()

	// set certs dir to minio directory
	consoleCerts.GlobalCertsDir = &consoleCerts.ConfigDir{

////

That command will create or modify some [environment variables](environment-variables.md){.internal-link target=_blank} that will be available for the next commands.

One of those variables is the `PATH` variable.

/// tip

You can learn more about the `PATH` environment variable in the [Environment Variables](environment-variables.md#path-environment-variable){.internal-link target=_blank} section.

///

Doing that in separated functions that don't share logic or variables together is more difficult as you would need to store values in global variables or similar tricks.

Because of that, it's now recommended to instead use the `lifespan` as explained above.

## Technical Details { #technical-details }

        "bar",
        "foo"
    ]
}
```

## Recap { #recap }

Declare headers with `Header`, using the same common pattern as `Query`, `Path` and `Cookie`.

## Caveat { #caveat }

If you need to perform heavy background computation and you don't necessarily need it to be run by the same process (for example, you don't need to share memory, variables, etc), you might benefit from using other bigger tools like <a href="https://docs.celeryq.dev" class="external-link" target="_blank">Celery</a>.