Die Middleware antwortet auf zwei besondere Arten von HTTP-Requests ...

### CORS-Preflight-Requests { #cors-preflight-requests }

Dies sind alle `OPTIONS`-Requests mit `Origin`- und `Access-Control-Request-Method`-Headern.

	cunlock := make(chan bool)
	cdone := make(chan bool)
	for range numReaders {
		go parallelReader(context.Background(), m, clocked, cunlock, cdone)
	}
	// Wait for all parallel RLock()s to succeed.
	for range numReaders {
		<-clocked
	}
	for range numReaders {
		cunlock <- true
	}
	// Wait for the goroutines to finish.
	for range numReaders {
		<-cdone
	}
}

O middleware responde a dois tipos específicos de solicitação HTTP...

### Requisições CORS pré-voo (preflight) { #cors-preflight-requests }

Estas são quaisquer solicitações `OPTIONS` com cabeçalhos `Origin` e `Access-Control-Request-Method`.

Nesse caso, o middleware interceptará a solicitação recebida e responderá com cabeçalhos CORS apropriados e uma resposta `200` ou `400` para fins informativos.

		return err
	}

	reason := googleAPIErr.Errors[0].Reason
	message := googleAPIErr.Errors[0].Message

	switch reason {
	case "required":
		// Anonymous users does not have storage.xyz access to project 123.
		fallthrough
	case "keyInvalid":
		fallthrough
	case "forbidden":
		err = PrefixAccessDenied{
			Bucket: bucket,
			Object: object,
		}
	case "invalid":

	cunlock := make(chan bool)
	cdone := make(chan bool)
	for range numReaders {
		go parallelReader(context.Background(), m, clocked, cunlock, cdone)
	}
	// Wait for all parallel RLock()s to succeed.
	for range numReaders {
		<-clocked
	}
	for range numReaders {
		cunlock <- true
	}
	// Wait for the goroutines to finish.
	for range numReaders {
		<-cdone
	}
}

### 2. Configure authentication type for Prometheus metrics

MinIO supports two authentication modes for Prometheus either `jwt` or `public`, by default MinIO runs in `jwt` mode. To allow public access without authentication for prometheus metrics set environment as follows.

```
export MINIO_PROMETHEUS_AUTH_TYPE="public"
minio server ~/test
```

### 3. Configuring Prometheus

For example, inside of an `async` *path operation function* you can get the contents with:

```Python
contents = await myfile.read()
```

If you are inside of a normal `def` *path operation function*, you can access the `UploadFile.file` directly, for example:

```Python
contents = myfile.file.read()
```

/// note | `async` Technical Details

	logger.LogIf(ctx, "tier", err, errKind...)
}

func kmsLogIf(ctx context.Context, err error, errKind ...any) {
	logger.LogIf(ctx, "kms", err, errKind...)
}

// KMSLogger permits access to kms module specific logging
type KMSLogger struct{}

// LogOnceIf is the implementation of LogOnceIf, accessible using the Logger interface

import importlib
import inspect as _inspect
import os as _os
import site as _site
import sys as _sys
import sysconfig

# pylint: disable=g-bad-import-order,protected-access,g-import-not-at-top
from tensorflow.python import pywrap_tensorflow  # pylint: disable=unused-import
from tensorflow.python.tools import module_util as _module_util
from tensorflow.python.platform import tf_logging as _logging

## Self-hosting JavaScript and CSS for docs { #self-hosting-javascript-and-css-for-docs }

Self-hosting the JavaScript and CSS could be useful if, for example, you need your app to keep working even while offline, without open Internet access, or in a local network.

Here you'll see how to serve those files yourself, in the same FastAPI app, and configure the docs to use them.

### Project file structure { #project-file-structure }