extract S3 bucket and key from value_from.url

example-files/rules/terraform.yml

@@ -141,8 +141,7 @@ Rules:
         key: instance_type
         op: in
         value_from:
-          bucket: config-rules-for-lambda
-          key: instance-types
+          url: s3://config-rules-for-lambda/instance-types
     severity: WARNING
     tags:
       - ec2

filter/engine.go

@@ -12,8 +12,7 @@ type Filter struct {
 }
 
 type FilterValueFrom struct {
-	Bucket string
-	Key    string
+	Url string
 }
 
 type ValueSource interface {

filter/value.go

@@ -6,19 +6,28 @@ import (
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/s3"
+	"net/url"
 )
 
 type StandardValueSource struct {
 	Log LoggingFunction
 }
 
 func (v StandardValueSource) GetValue(filter Filter) string {
-	if filter.ValueFrom.Bucket != "" {
-		v.Log(fmt.Sprintf("Getting value_from s3://%s/%s", filter.ValueFrom.Bucket, filter.ValueFrom.Key))
-		content, err := v.GetValueFromS3(filter.ValueFrom.Bucket, filter.ValueFrom.Key)
+	if filter.ValueFrom.Url != "" {
+		v.Log(fmt.Sprintf("Getting value_from %s", filter.ValueFrom.Url))
+		parsedURL, err := url.Parse(filter.ValueFrom.Url)
+		if err != nil {
+			panic(err)
+		}
+		if parsedURL.Scheme != "s3" && parsedURL.Scheme != "S3" {
+			panic(fmt.Sprintf("Unsupported protocol for value_from: %s", parsedURL.Scheme))
+		}
+		content, err := v.GetValueFromS3(parsedURL.Host, parsedURL.Path)
 		if err != nil {
 			return "Error" // FIXME
 		}
+		v.Log(content)
 		return content
 	}
 	return filter.Value