FEATURE: Use path from existing URL of uploads and optimized images (#13177)

Discourse shouldn't dynamically calculate the path of uploads and optimized images after a file has been stored on disk or S3. Otherwise it might calculate the wrong path if the SHA1 or extension stored in the database doesn't match the actual file path.

lib/file_store/base_store.rb

@@ -3,13 +3,17 @@
 module FileStore
 
   class BaseStore
+    UPLOAD_PATH_REGEX = %r|/(original/\d+X/.*)|
+    OPTIMIZED_IMAGE_PATH_REGEX = %r|/(optimized/\d+X/.*)|
 
     def store_upload(file, upload, content_type = nil)
+      upload.url = nil
       path = get_path_for_upload(upload)
       store_file(file, path)
     end
 
     def store_optimized_image(file, optimized_image, content_type = nil, secure: false)
+      optimized_image.url = nil
       path = get_path_for_optimized_image(optimized_image)
       store_file(file, path)
     end
@@ -116,6 +120,12 @@ module FileStore
     end
 
     def get_path_for_upload(upload)
+      # try to extract the path from the URL instead of calculating it,
+      # because the calculated path might differ from the actual path
+      if upload.url.present? && (path = upload.url[UPLOAD_PATH_REGEX, 1])
+        return prefix_path(path)
+      end
+
       extension =
         if upload.extension
           ".#{upload.extension}"
@@ -128,6 +138,12 @@ module FileStore
     end
 
     def get_path_for_optimized_image(optimized_image)
+      # try to extract the path from the URL instead of calculating it,
+      # because the calculated path might differ from the actual path
+      if optimized_image.url.present? && (path = optimized_image.url[OPTIMIZED_IMAGE_PATH_REGEX, 1])
+        return prefix_path(path)
+      end
+
       upload = optimized_image.upload
       version = optimized_image.version || 1
       extension = "_#{version}_#{optimized_image.width}x#{optimized_image.height}#{optimized_image.extension}"
@@ -178,6 +194,9 @@ module FileStore
       depths.max
     end
 
+    def prefix_path(path)
+      path
+    end
   end
 
 end

lib/file_store/local_store.rb

@@ -66,7 +66,7 @@ module FileStore
     end
 
     def get_path_for(type, upload_id, sha, extension)
-      File.join("/", upload_path, super(type, upload_id, sha, extension))
+      prefix_path(super(type, upload_id, sha, extension))
     end
 
     def copy_file(file, path)
@@ -134,5 +134,8 @@ module FileStore
       puts "#{count} of #{model.count} #{model.name.underscore.pluralize} are missing" if count > 0
     end
 
+    def prefix_path(path)
+      File.join("/", upload_path, path)
+    end
   end
 end

lib/file_store/s3_store.rb

@@ -22,6 +22,7 @@ module FileStore
     end
 
     def store_upload(file, upload, content_type = nil)
+      upload.url = nil
       path = get_path_for_upload(upload)
       url, upload.etag = store_file(
         file,
@@ -35,6 +36,7 @@ module FileStore
     end
 
     def store_optimized_image(file, optimized_image, content_type = nil, secure: false)
+      optimized_image.url = nil
       path = get_path_for_optimized_image(optimized_image)
       url, optimized_image.etag = store_file(file, path, content_type: content_type, private_acl: secure)
       url