success: false,
		},
		// invalid json.
		{

		},
		// Success case, no multipart filename.
		{
			objectName:         "test",
			data:               []byte("Hello, World"),

	if err != nil {
		t.Fatal(err)
	}

  "requestPath": "/testbucket/hosts",
  "requestHost": "localhost:9000",
  "requestHeader": {
    "Accept-Encoding": "zstd,gzip",
    "Authorization": "AWS4-HMAC-SHA256 Credential=minioadmin/20240509/us-east-1/s3/aws4_request,SignedHeaders=host;x-amz-content-sha256;x-amz-date;x-amz-decoded-content-length,Signature=d4d6862e6cc61011a61fa801da71048ece4f32a0562cad6bb88bdda50d7fcb95",
    "Content-Length": "401",

		canonicalHeaders,
		signedHeaders,
		hashedPayload,
	}, "\n")

	// Get scope.
	scope := strings.Join([]string{
		currTime.Format(yyyymmdd),
		globalMinioDefaultRegion,
		string(serviceS3),
		"aws4_request",
	}, SlashSeparator)

	stringToSign := "AWS4-HMAC-SHA256" + "\n" + currTime.Format(iso8601Format) + "\n"
	stringToSign += scope + "\n"
	stringToSign += getSHA256Hash([]byte(canonicalRequest))

	now := UTCNow()

	req = signer.StreamingUnsignedV4(req, "", 8, now)

	maliciousHeaders := http.Header{
		"Authorization":                []string{fmt.Sprintf("AWS4-HMAC-SHA256 Credential=%s/%s/us-east-1/s3/aws4_request, SignedHeaders=invalidheader, Signature=deadbeefdeadbeefdeadbeeddeadbeeddeadbeefdeadbeefdeadbeefdeadbeef", s.accessKey, now.Format(yyyymmdd))},
		"User-Agent":                   []string{"A malicious request"},

```
curl -v $(go run presigned.go)
...
...
> GET /functionbucket/testobject?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=minioadmin%2F20230205%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20230205T173023Z&X-Amz-Expires=1000&X-Amz-SignedHeaders=host&lambdaArn=arn%3Aminio%3As3-object-lambda%3A%3Atoupper%3Awebhook&X-Amz-Signature=d7e343f0da9d4fa2bc822c12ad2f54300ff16796a1edaa6d31f1313c8e94d5b2 HTTP/1.1