return psv, ErrInvalidQuerySignatureAlgo
	}

	// Initialize signature version '4' structured header.
	preSignV4Values := preSignValues{}

	// Save credential.
	preSignV4Values.Credential, aec = parseCredentialHeader("Credential="+query.Get(xhttp.AmzCredential), region, stype)
	if aec != ErrNone {
		return psv, aec
	}

	var e error
	// Save date in native time.Time.

	}
	return s.String()
}

// IsExpired - returns whether Credential is expired or not.
func (cred Credentials) IsExpired() bool {
	if cred.Expiration.IsZero() || cred.Expiration.Equal(timeSentinel) {
		return false
	}

	return cred.Expiration.Before(time.Now().UTC())
}

// IsTemp - returns whether credential is temporary or not.
func (cred Credentials) IsTemp() bool {

	}
}

// TestParseCredentialHeader - validates the format validator and extractor for the Credential header in an aws v4 request.
// A valid format of credential should be of the following format.
// Credential = accessKey + SlashSeparator+ scope
// where scope = string.Join([]string{  currTime.Format(yyyymmdd),
//
//				globalMinioDefaultRegion,
//	              	"s3",

		formData       map[string]string
	}{
		{http.StatusForbidden, credentials.SecretKey, map[string]string{"AWSAccessKeyId": "invalidaccesskey"}},
		{http.StatusForbidden, "invalidsecretkey", map[string]string{"AWSAccessKeyId": credentials.AccessKey}},
		{http.StatusNoContent, credentials.SecretKey, map[string]string{"AWSAccessKeyId": credentials.AccessKey}},
		{http.StatusForbidden, credentials.SecretKey, map[string]string{"Awsaccesskeyid": "invalidaccesskey"}},

		ccred          Credentials
		expectedResult bool
	}{
		// Same Credentialss.
		{cred, cred, true},
		// Empty credentials to compare.
		{cred, Credentials{}, false},
		// Empty credentials.
		{Credentials{}, cred, false},
		// Two different credentialss
		{cred, cred2, false},
		// Access key is different in credentials to compare.
		{cred, Credentials{AccessKey: "myuser", SecretKey: cred.SecretKey}, false},

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

	}{
		{"shastring", "", "shastring"},
		{emptySHA256, "", emptySHA256},
		{"", "", emptySHA256},
		{"", "X-Amz-Credential=random", unsignedPayload},
		{"", "X-Amz-Credential=random&X-Amz-Content-Sha256=" + unsignedPayload, unsignedPayload},
		{"", "X-Amz-Credential=random&X-Amz-Content-Sha256=shastring", "shastring"},
	}

	for i, testCase := range testCases {

	testCases := []struct {
		form     http.Header
		expected APIErrorCode
	}{
		// (0) It should fail if 'X-Amz-Credential' is missing.
		{
			form:     http.Header{},
			expected: ErrCredMalformed,
		},
		// (1) It should fail if the access key is incorrect.
		{
			form: http.Header{
				"X-Amz-Credential": []string{fmt.Sprintf(credentialTemplate, "EXAMPLEINVALIDEXAMPL", now.Format(yyyymmdd), globalMinioDefaultRegion)},
			},

	)

	ErrInvalidRootUserCredentials = newErrFn(
		"Invalid credentials",
		"Please provide correct credentials",
		EnvRootUser+` length should be at least 3, and `+EnvRootPassword+` length at least 8 characters`,
	)

	ErrMissingEnvCredentialRootUser = newErrFn(
		"Missing credential environment variable, \""+EnvRootUser+"\"",
		"Environment variable \""+EnvRootUser+"\" is missing",

		"s3:GetObject",
		"s3:PutObject"
	  ],
	  "Effect": "Allow",
	  "Resource": ["arn:aws:s3:::mybucket/${aws:username}/*"]
	}
  ]
}
```

If the user is authenticating using an STS credential which was authorized from OpenID connect we allow all `jwt:*` variables specified in the JWT specification, custom `jwt:*` or extensions are not supported. List of policy variables for OpenID based STS.

- `jwt:sub`
- `jwt:iss`