Renaming to assume_role_arn, it's more descriptive and added to readme

Signed-off-by: Long Nguyen <nguyenlo@vmware.com>

Author: Long Nguyen

README.md

@@ -58,6 +58,8 @@ bucket.
 * `secret_access_key`: *Required.* The AWS secret key to use when accessing
 the bucket.
 
+* `assume_role_arn`: *Optional.* The AWS role to assume when using access keys.
+
 * `session_token`: *Optional.* The AWS session token to use when accessing
 the bucket.
 

driver/driver.go

@@ -76,8 +76,8 @@ func FromSource(source models.Source) (Driver, error) {
 		s3Session := session.New(awsConfig)
 
 		var s3Client *s3.S3
-		if source.RoleArn != "" {
-			creds := stscreds.NewCredentials(s3Session, source.RoleArn)
+		if source.AssumeRoleArn != "" {
+			creds := stscreds.NewCredentials(s3Session, source.AssumeRoleArn)
 			s3Client = s3.New(s3Session, &aws.Config{Credentials: creds})
 		} else {
 			s3Client = s3.New(s3Session)
@@ -102,15 +102,15 @@ func FromSource(source models.Source) (Driver, error) {
 		return &GitDriver{
 			InitialVersion: initialVersion,
 
-			URI:                    source.URI,
-			Branch:                 source.Branch,
-			PrivateKey:             source.PrivateKey,
-			Username:               source.Username,
-			Password:               source.Password,
-			File:                   source.File,
-			GitUser:                source.GitUser,
-			CommitMessage:          source.CommitMessage,
-			SkipSSLVerification:    source.SkipSSLVerification,
+			URI:                 source.URI,
+			Branch:              source.Branch,
+			PrivateKey:          source.PrivateKey,
+			Username:            source.Username,
+			Password:            source.Password,
+			File:                source.File,
+			GitUser:             source.GitUser,
+			CommitMessage:       source.CommitMessage,
+			SkipSSLVerification: source.SkipSSLVerification,
 		}, nil
 
 	case models.DriverSwift:

models/models.go

@@ -62,7 +62,7 @@ type Source struct {
 	Key                  string `json:"key"`
 	AccessKeyID          string `json:"access_key_id"`
 	SecretAccessKey      string `json:"secret_access_key"`
-	RoleArn              string `json:"role_arn"`
+	AssumeRoleArn        string `json:"assume_role_arn"`
 	SessionToken         string `json:"session_token"`
 	RegionName           string `json:"region_name"`
 	Endpoint             string `json:"endpoint"`