connector: customendpoint flag for NewAWSReader

Workaround to use min.io or other compatible service as s3 backend
Using custom region as flag to indicate that we are not using
aws services.

connector.go

@@ -53,17 +53,32 @@ func NewAWSReader(
 	ctx context.Context, accessKey string, secretKey string, regions []string, config *aws.Config,
 ) (AWSReader, error) {
 	var c = connector{}
+	const customEndpointRegion string = "custom"
 
 	creds, ec2s, sts, err := configureAWS(accessKey, secretKey)
 	if err != nil {
 		return nil, err
 	}
 	c.creds = creds
-	if err := c.setAccountID(ctx, sts); err != nil {
-		return nil, err
+
+	// Workaround to use with min.io as s3 backend
+	// Using custom region as flag to indicate that we are not using aws services.
+	customEndpoint := false
+	for _, region := range regions {
+		if region == customEndpointRegion {
+			customEndpoint = true
+			break
+		}
 	}
-	if err := c.setRegions(ctx, ec2s, regions); err != nil {
-		return nil, err
+	if customEndpoint {
+		c.regions = regions
+	} else {
+		if err := c.setAccountID(ctx, sts); err != nil {
+			return nil, err
+		}
+		if err := c.setRegions(ctx, ec2s, regions); err != nil {
+			return nil, err
+		}
 	}
 	c.setServices(config)
 	return &c, nil