Name return values to prevent the need (and unnecessary code bloat) (#4576)

This is done to explicitly instantiate objects for every return statement.

cmd/signature-v4-parser.go

@@ -45,20 +45,20 @@ func (c credentialHeader) getScope() string {
 }
 
 // parse credentialHeader string into its structured form.
-func parseCredentialHeader(credElement string) (credentialHeader, APIErrorCode) {
+func parseCredentialHeader(credElement string) (ch credentialHeader, aec APIErrorCode) {
 	creds := strings.Split(strings.TrimSpace(credElement), "=")
 	if len(creds) != 2 {
-		return credentialHeader{}, ErrMissingFields
+		return ch, ErrMissingFields
 	}
 	if creds[0] != "Credential" {
-		return credentialHeader{}, ErrMissingCredTag
+		return ch, ErrMissingCredTag
 	}
 	credElements := strings.Split(strings.TrimSpace(creds[1]), "/")
 	if len(credElements) != 5 {
-		return credentialHeader{}, ErrCredMalformed
+		return ch, ErrCredMalformed
 	}
 	if !isAccessKeyValid(credElements[0]) {
-		return credentialHeader{}, ErrInvalidAccessKeyID
+		return ch, ErrInvalidAccessKeyID
 	}
 	// Save access key id.
 	cred := credentialHeader{
@@ -67,15 +67,15 @@ func parseCredentialHeader(credElement string) (credentialHeader, APIErrorCode)
 	var e error
 	cred.scope.date, e = time.Parse(yyyymmdd, credElements[1])
 	if e != nil {
-		return credentialHeader{}, ErrMalformedCredentialDate
+		return ch, ErrMalformedCredentialDate
 	}
 	cred.scope.region = credElements[2]
 	if credElements[3] != "s3" {
-		return credentialHeader{}, ErrInvalidService
+		return ch, ErrInvalidService
 	}
 	cred.scope.service = credElements[3]
 	if credElements[4] != "aws4_request" {
-		return credentialHeader{}, ErrInvalidRequestVersion
+		return ch, ErrInvalidRequestVersion
 	}
 	cred.scope.request = credElements[4]
 	return cred, ErrNone
@@ -148,17 +148,17 @@ func doesV4PresignParamsExist(query url.Values) APIErrorCode {
 }
 
 // Parses all the presigned signature values into separate elements.
-func parsePreSignV4(query url.Values) (preSignValues, APIErrorCode) {
+func parsePreSignV4(query url.Values) (psv preSignValues, aec APIErrorCode) {
 	var err APIErrorCode
 	// verify whether the required query params exist.
 	err = doesV4PresignParamsExist(query)
 	if err != ErrNone {
-		return preSignValues{}, err
+		return psv, err
 	}
 
 	// Verify if the query algorithm is supported or not.
 	if query.Get("X-Amz-Algorithm") != signV4Algorithm {
-		return preSignValues{}, ErrInvalidQuerySignatureAlgo
+		return psv, ErrInvalidQuerySignatureAlgo
 	}
 
 	// Initialize signature version '4' structured header.
@@ -167,35 +167,35 @@ func parsePreSignV4(query url.Values) (preSignValues, APIErrorCode) {
 	// Save credential.
 	preSignV4Values.Credential, err = parseCredentialHeader("Credential=" + query.Get("X-Amz-Credential"))
 	if err != ErrNone {
-		return preSignValues{}, err
+		return psv, err
 	}
 
 	var e error
 	// Save date in native time.Time.
 	preSignV4Values.Date, e = time.Parse(iso8601Format, query.Get("X-Amz-Date"))
 	if e != nil {
-		return preSignValues{}, ErrMalformedPresignedDate
+		return psv, ErrMalformedPresignedDate
 	}
 
 	// Save expires in native time.Duration.
 	preSignV4Values.Expires, e = time.ParseDuration(query.Get("X-Amz-Expires") + "s")
 	if e != nil {
-		return preSignValues{}, ErrMalformedExpires
+		return psv, ErrMalformedExpires
 	}
 
 	if preSignV4Values.Expires < 0 {
-		return preSignValues{}, ErrNegativeExpires
+		return psv, ErrNegativeExpires
 	}
 	// Save signed headers.
 	preSignV4Values.SignedHeaders, err = parseSignedHeader("SignedHeaders=" + query.Get("X-Amz-SignedHeaders"))
 	if err != ErrNone {
-		return preSignValues{}, err
+		return psv, err
 	}
 
 	// Save signature.
 	preSignV4Values.Signature, err = parseSignature("Signature=" + query.Get("X-Amz-Signature"))
 	if err != ErrNone {
-		return preSignValues{}, err
+		return psv, err
 	}
 
 	// Return structed form of signature query string.
@@ -207,25 +207,25 @@ func parsePreSignV4(query url.Values) (preSignValues, APIErrorCode) {
 //    Authorization: algorithm Credential=accessKeyID/credScope, \
 //            SignedHeaders=signedHeaders, Signature=signature
 //
-func parseSignV4(v4Auth string) (signValues, APIErrorCode) {
+func parseSignV4(v4Auth string) (sv signValues, aec APIErrorCode) {
 	// Replace all spaced strings, some clients can send spaced
 	// parameters and some won't. So we pro-actively remove any spaces
 	// to make parsing easier.
 	v4Auth = strings.Replace(v4Auth, " ", "", -1)
 	if v4Auth == "" {
-		return signValues{}, ErrAuthHeaderEmpty
+		return sv, ErrAuthHeaderEmpty
 	}
 
 	// Verify if the header algorithm is supported or not.
 	if !strings.HasPrefix(v4Auth, signV4Algorithm) {
-		return signValues{}, ErrSignatureVersionNotSupported
+		return sv, ErrSignatureVersionNotSupported
 	}
 
 	// Strip off the Algorithm prefix.
 	v4Auth = strings.TrimPrefix(v4Auth, signV4Algorithm)
 	authFields := strings.Split(strings.TrimSpace(v4Auth), ",")
 	if len(authFields) != 3 {
-		return signValues{}, ErrMissingFields
+		return sv, ErrMissingFields
 	}
 
 	// Initialize signature version '4' structured header.
@@ -235,19 +235,19 @@ func parseSignV4(v4Auth string) (signValues, APIErrorCode) {
 	// Save credentail values.
 	signV4Values.Credential, err = parseCredentialHeader(authFields[0])
 	if err != ErrNone {
-		return signValues{}, err
+		return sv, err
 	}
 
 	// Save signed headers.
 	signV4Values.SignedHeaders, err = parseSignedHeader(authFields[1])
 	if err != ErrNone {
-		return signValues{}, err
+		return sv, err
 	}
 
 	// Save signature.
 	signV4Values.Signature, err = parseSignature(authFields[2])
 	if err != ErrNone {
-		return signValues{}, err
+		return sv, err
 	}
 
 	// Return the structure here.