{
			policy:  `{"conditions":[["eq","$bucket","asdf"],["eq","$key","hello.txt"]],"conditions":[["eq","$success_action_status","201"],["eq","$Content-Type","plain/text"],["eq","$success_action_status","201"],["eq","$x-amz-algorithm","AWS4-HMAC-SHA256"],["eq","$x-amz-credential","Q3AM3UQ867SPQQA43P2F/20210315/us-east-1/s3/aws4_request"],["eq","$x-amz-date","20210315T091621Z"]]}`,
			success: false,
		},
		// invalid json.
		{

	contentLengthCondStr := `["content-length-range", 1024, 1048576]`
	// Add the algorithm condition, only accept AWS SignV4 Sha256.
	algorithmConditionStr := `["eq", "$x-amz-algorithm", "AWS4-HMAC-SHA256"]`
	// Add the date condition, only accept the current date.
	dateConditionStr := fmt.Sprintf(`["eq", "$x-amz-date", "%s"]`, t.Format(iso8601DateFormat))
	// Add the credential string, only accept the credential passed.

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

	streamingContentSHA256        = "STREAMING-AWS4-HMAC-SHA256-PAYLOAD"
	streamingContentSHA256Trailer = "STREAMING-AWS4-HMAC-SHA256-PAYLOAD-TRAILER"
	signV4ChunkedAlgorithm        = "AWS4-HMAC-SHA256-PAYLOAD"
	signV4ChunkedAlgorithmTrailer = "AWS4-HMAC-SHA256-TRAILER"
	streamingContentEncoding      = "aws-chunked"
	awsTrailerHeader              = "X-Amz-Trailer"

		filterLegalHold bool
		expected        map[string]string
	}{
		{
			metadata: map[string]string{
				"Authorization":        "AWS4-HMAC-SHA256 <cred_string>",
				"X-Amz-Content-Sha256": "",
				"Content-Encoding":     "",
			},
			expected: map[string]string{
				"Authorization":        "AWS4-HMAC-SHA256 <cred_string>",
				"X-Amz-Content-Sha256": "",
				"Content-Encoding":     "",
			},
		},
		{

  "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",

	"github.com/minio/minio/internal/auth"
	"github.com/minio/minio/internal/hash/sha256"
	xhttp "github.com/minio/minio/internal/http"
)

// AWS Signature Version '4' constants.
const (
	signV4Algorithm = "AWS4-HMAC-SHA256"
	iso8601Format   = "20060102T150405Z"
	yyyymmdd        = "20060102"
)

type serviceType string

const (
	serviceS3  serviceType = "s3"
	serviceSTS serviceType = "sts"
)

		globalMinioDefaultRegion,
		string(serviceS3),
		"aws4_request",
	}, SlashSeparator)

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

	date := sumHMAC([]byte("AWS4"+secretKey), []byte(currTime.Format(yyyymmdd)))
	region := sumHMAC(date, []byte(globalMinioDefaultRegion))

	}
	fmt.Println(presignedURL)
}
```

Use the Presigned URL via `curl` to receive the transformed object.
```
curl -v $(go run presigned.go)
...
...

		{
			req: &http.Request{
				URL: &url.URL{
					Host:   "127.0.0.1:9000",
					Scheme: httpScheme,
					Path:   SlashSeparator,
				},
				Header: http.Header{
					"Authorization":        []string{"AWS4-HMAC-SHA256 <cred_string>"},
					"X-Amz-Content-Sha256": []string{streamingContentSHA256},
					"Content-Encoding":     []string{streamingContentEncoding},
				},
				Method: http.MethodPut,
				Body:   nopCloser,
			},