Merge pull request rails#42509 from maleblond/add-cache-control-support-active-support-gcs

Support default `cache_control` in GCS Active Storage

Author: rafaelfranca

activestorage/CHANGELOG.md

@@ -1,3 +1,12 @@
+*   Allow setting a `Cache-Control` on files uploaded to GCS.
+    
+    ```yaml
+    gcs:
+      service: GCS
+      ...
+      cache_control: "public, max-age=3600"
+    ``` 
+    *maleblond*
 
 *   The parameters sent to `ffmpeg` for generating a video preview image are now
     configurable under `config.active_storage.video_preview_arguments`.

activestorage/lib/active_storage/service/gcs_service.rb

@@ -19,7 +19,7 @@ def upload(key, io, checksum: nil, content_type: nil, disposition: nil, filename
         # binary and attachment when the file's content type requires it. The only way to force them is to
         # store them as object's metadata.
         content_disposition = content_disposition_with(type: disposition, filename: filename) if disposition && filename
-        bucket.create_file(io, key, md5: checksum, content_type: content_type, content_disposition: content_disposition)
+        bucket.create_file(io, key, md5: checksum, cache_control: @config[:cache_control], content_type: content_type, content_disposition: content_disposition)
       rescue Google::Cloud::InvalidArgumentError
         raise ActiveStorage::IntegrityError
       end
@@ -84,7 +84,24 @@ def exist?(key)
 
     def url_for_direct_upload(key, expires_in:, checksum:, **)
       instrument :url, key: key do |payload|
-        generated_url = bucket.signed_url key, method: "PUT", expires: expires_in, content_md5: checksum
+        headers = {}
+        version = :v2
+
+        if @config[:cache_control].present?
+          headers["Cache-Control"] = @config[:cache_control]
+          # v2 signing doesn't support non `x-goog-` headers. Only switch to v4 signing
+          # if necessary for back-compat; v4 limits the expiration of the URL to 7 days
+          # whereas v2 has no limit
+          version = :v4
+        end
+
+        generated_url = bucket.signed_url(key,
+          content_md5: checksum,
+          expires: expires_in,
+          headers: headers,
+          method: "PUT",
+          version: version
+        )
 
         payload[:url] = generated_url
 
@@ -95,7 +112,13 @@ def url_for_direct_upload(key, expires_in:, checksum:, **)
     def headers_for_direct_upload(key, checksum:, filename: nil, disposition: nil, **)
       content_disposition = content_disposition_with(type: disposition, filename: filename) if filename
 
-      { "Content-MD5" => checksum, "Content-Disposition" => content_disposition }
+      headers = { "Content-MD5" => checksum, "Content-Disposition" => content_disposition }
+
+      if @config[:cache_control].present?
+        headers["Cache-Control"] = @config[:cache_control]
+      end
+
+      headers
     end
 
     private
@@ -137,7 +160,7 @@ def bucket
       end
 
       def client
-        @client ||= Google::Cloud::Storage.new(**config.except(:bucket))
+        @client ||= Google::Cloud::Storage.new(**config.except(:bucket, :cache_control))
       end
   end
 end

activestorage/test/service/gcs_service_test.rb

@@ -57,6 +57,36 @@ class ActiveStorage::Service::GCSServiceTest < ActiveSupport::TestCase
       @service.delete key
     end
 
+    test "direct upload with cache control" do
+      config_with_cache_control = { gcs: service_config[:gcs].merge({ cache_control: "public, max-age=1800" }) }
+      service = ActiveStorage::Service.configure(:gcs, config_with_cache_control)
+
+      key      = SecureRandom.base58(24)
+      data     = "Some text"
+      checksum = Digest::MD5.base64digest(data)
+      url      = service.url_for_direct_upload(key, expires_in: 5.minutes, content_type: "text/plain", content_length: data.size, checksum: checksum)
+
+      uri = URI.parse url
+      request = Net::HTTP::Put.new uri.request_uri
+      request.body = data
+      headers = service.headers_for_direct_upload(key, checksum: checksum, filename: ActiveStorage::Filename.new("test.txt"), disposition: :attachment)
+      assert_equal(headers["Cache-Control"], "public, max-age=1800")
+
+      headers.each do |k, v|
+        request.add_field k, v
+      end
+      request.add_field "Content-Type", ""
+      Net::HTTP.start(uri.host, uri.port, use_ssl: true) do |http|
+        http.request request
+      end
+
+      url = service.url(key, expires_in: 2.minutes, disposition: :inline, content_type: "text/html", filename: ActiveStorage::Filename.new("test.html"))
+      response = Net::HTTP.get_response(URI(url))
+      assert_equal("public, max-age=1800", response["Cache-Control"])
+    ensure
+      service.delete(key)
+    end
+
     test "upload with content_type and content_disposition" do
       key      = SecureRandom.base58(24)
       data     = "Something else entirely!"
@@ -85,6 +115,23 @@ class ActiveStorage::Service::GCSServiceTest < ActiveSupport::TestCase
       @service.delete key
     end
 
+    test "upload with cache_control" do
+      key      = SecureRandom.base58(24)
+      data     = "Something else entirely!"
+
+      config_with_cache_control = { gcs: service_config[:gcs].merge({ cache_control: "public, max-age=1800" }) }
+      service = ActiveStorage::Service.configure(:gcs, config_with_cache_control)
+
+      service.upload(key, StringIO.new(data), checksum: Digest::MD5.base64digest(data), content_type: "text/plain")
+
+      url = service.url(key, expires_in: 2.minutes, disposition: :inline, content_type: "text/html", filename: ActiveStorage::Filename.new("test.html"))
+
+      response = Net::HTTP.get_response(URI(url))
+      assert_equal "public, max-age=1800", response["Cache-Control"]
+    ensure
+      service.delete key
+    end
+
     test "update metadata" do
       key      = SecureRandom.base58(24)
       data     = "Something else entirely!"

guides/source/active_storage_overview.md

@@ -235,6 +235,15 @@ google:
   bucket: ""
 ```
 
+Optionally provide a Cache-Control metadata to set on uploaded assets:
+
+```yaml
+google:
+  service: GCS
+  ...
+  cache_control: "public, max-age=3600"
+```
+
 Add the [`google-cloud-storage`](https://github.com/GoogleCloudPlatform/google-cloud-ruby/tree/master/google-cloud-storage) gem to your `Gemfile`:
 
 ```ruby
@@ -822,6 +831,7 @@ Take care to allow:
   * `Content-Disposition` (except for Azure Storage)
   * `x-ms-blob-content-disposition` (for Azure Storage only)
   * `x-ms-blob-type` (for Azure Storage only)
+  * `Cache-Control` (for GCS, only if `cache_control` is set)
 
 No CORS configuration is required for the Disk service since it shares your app’s origin.