Add support for CacheControl header

DOCS.md

@@ -10,6 +10,7 @@ Use the S3 sync plugin to synchronize files and folders with an Amazon S3 bucket
 * `delete` - deletes files in the target not found in the source
 * `content_type` - override default mime-types to use this value
 * `content_encoding` - override default content encoding header for files
+* `cache_control` - override default cache control header for files
 * `metadata` - set custom metadata
 * `redirects` - targets that should redirect elsewhere
 * `cloudfront_distribution_id` - (optional) the cloudfront distribution id to invalidate after syncing
@@ -30,7 +31,7 @@ publish:
     cloudfront_distribution_id: "9c5785d3ece6a9cdefa4"
 ```
 
-The `acl`, `content_type`, and `content_encoding` parameters can be passed as a string value to apply to all files, or as a map to apply to a subset of files.
+The `acl`, `content_type`, `cache_control`, and `content_encoding` parameters can be passed as a string value to apply to all files, or as a map to apply to a subset of files.
 
 For example:
 
@@ -45,6 +46,7 @@ publish:
     content_encoding:
       ".js": gzip
       ".css": gzip
+    cache_control: "public, max-age: 31536000"
     region: "us-east-1"
     bucket: "my-bucket.s3-website-us-east-1.amazonaws.com"
     access_key: "970d28f4dd477bc184fbd10b376de753"
@@ -61,6 +63,9 @@ The `content_type` field the key is an extension including the leading dot `.`.
 In the  `content_encoding` field the key is an extension including the leading dot `.`. If you want to set a encoding type for files with no extension, set the key
 to th empty string `""`. If there are no matches for the `content_encoding` of a file, no content-encoding header will be added.
 
+In the  `cache_control` field the key is an extension including the leading dot `.`. If you want to set cahce control for files with no extension, set the key
+to th empty string `""`. If there are no matches for the `cache_control` of a file, no cache-control header will be added.
+
 The `metadata` field can be set as either an object where the keys are the metadata headers:
 
 ```yaml
@@ -75,7 +80,7 @@ publish:
     target: /target/location
     delete: true
     metadata:
-      Cache-Control: "max-age: 10000"
+      custom-meta: "abc123"
 ```
 
 Or you can specify metadata for file patterns by using a glob:
@@ -93,9 +98,7 @@ publish:
     delete: true
     metadata:
       "*.png":
-        Cache-Control: "max-age: 10000000"
-      "*.html":
-        Cache-Control: "max-age: 1000"
+        CustomMeta: "abc123"
 ```
 
 Additionally, you can specify redirect targets for files that don't exist by using the `redirects` key:

aws.go

@@ -52,7 +52,7 @@ func (a *AWS) Upload(local, remote string) error {
 
 	defer file.Close()
 
-	access := ""
+	var access string
 	for pattern := range p.Access {
 		if match := glob.Glob(pattern, local); match == true {
 			access = p.Access[pattern]
@@ -86,6 +86,14 @@ func (a *AWS) Upload(local, remote string) error {
 		}
 	}
 
+	var cacheControl string
+	for pattern := range p.CacheControl {
+		if match := glob.Glob(pattern, local); match == true {
+			cacheControl = p.CacheControl[pattern]
+			break
+		}
+	}
+
 	metadata := map[string]*string{}
 	for pattern := range p.Metadata {
 		if match := glob.Glob(pattern, local); match == true {
@@ -115,6 +123,10 @@ func (a *AWS) Upload(local, remote string) error {
 			Metadata:    metadata,
 		}
 
+		if len(cacheControl) > 0 {
+			putObject.CacheControl = aws.String(cacheControl)
+		}
+
 		if len(contentEncoding) > 0 {
 			putObject.ContentEncoding = aws.String(contentEncoding)
 		}
@@ -150,6 +162,16 @@ func (a *AWS) Upload(local, remote string) error {
 			shouldCopy = true
 		}
 
+		if !shouldCopy && head.CacheControl == nil && cacheControl != "" {
+			debug("Cache-Control has changed from unset to %s", cacheControl)
+			shouldCopy = true
+		}
+
+		if !shouldCopy && head.CacheControl != nil && cacheControl != *head.CacheControl {
+			debug("Cache-Control has changed from %s to %s", *head.CacheControl, cacheControl)
+			shouldCopy = true
+		}
+
 		if !shouldCopy && len(head.Metadata) != len(metadata) {
 			debug("Count of metadata values has changed for %s", local)
 			shouldCopy = true
@@ -216,6 +238,10 @@ func (a *AWS) Upload(local, remote string) error {
 			MetadataDirective: aws.String("REPLACE"),
 		}
 
+		if len(cacheControl) > 0 {
+			copyObject.CacheControl = aws.String(cacheControl)
+		}
+
 		if len(contentEncoding) > 0 {
 			copyObject.ContentEncoding = aws.String(contentEncoding)
 		}
@@ -238,6 +264,10 @@ func (a *AWS) Upload(local, remote string) error {
 			Metadata:    metadata,
 		}
 
+		if len(cacheControl) > 0 {
+			putObject.CacheControl = aws.String(cacheControl)
+		}
+
 		if len(contentEncoding) > 0 {
 			putObject.ContentEncoding = aws.String(contentEncoding)
 		}

main.go

@@ -74,6 +74,12 @@ func main() {
 			EnvVar: "PLUGIN_CONTENT_ENCODING",
 			Value:  &StringMapFlag{},
 		},
+		cli.GenericFlag{
+			Name:   "cache-control",
+			Usage:  "cache-control settings for uploads",
+			EnvVar: "PLUGIN_CACHE_CONTROL",
+			Value:  &StringMapFlag{},
+		},
 		cli.GenericFlag{
 			Name:   "metadata",
 			Usage:  "additional metadata for uploads",
@@ -116,6 +122,7 @@ func run(c *cli.Context) error {
 		Target:                 c.String("target"),
 		Delete:                 c.Bool("delete"),
 		Access:                 c.Generic("access").(*StringMapFlag).Get(),
+		CacheControl:           c.Generic("cache-control").(*StringMapFlag).Get(),
 		ContentType:            c.Generic("content-type").(*StringMapFlag).Get(),
 		ContentEncoding:        c.Generic("content-encoding").(*StringMapFlag).Get(),
 		Metadata:               c.Generic("metadata").(*DeepStringMapFlag).Get(),

plugin.go

@@ -17,6 +17,7 @@ type Plugin struct {
 	Target                 string
 	Delete                 bool
 	Access                 map[string]string
+	CacheControl           map[string]string
 	ContentType            map[string]string
 	ContentEncoding        map[string]string
 	Metadata               map[string]map[string]string