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---
category: framework-deep-dive
menu-title: Custom upload adapter
+classes: custom-adapter
---
# Custom image upload adapter
+In this guide you will learn the basic concepts of the file upload architecture in CKEditor 5 WYSIWYG editor which will help you implement your own custom upload adapter.
+
+While this guide is mainly focused on the image upload (the most common kind of upload), keep in mind that the presented concepts and the API allow developing all sorts of file upload adapters for different file types like documents or media.
+
Term | +Description | +
---|---|
Upload adapter | +
+ A piece of code (a class) that handles the image upload from the moment it is requested by the user (e.g. when the file is dropped into the content) to the moment a server returns a response to the requested upload. A bridge between the feature and the server. +Upload adapters are used by other plugins like {@link module:image/imageupload~ImageUpload `ImageUpload`} to connect to the server and fetch the response. For every user action (e.g. when a file is dropped into the content), a new upload adapter instance is created. +CKEditor 5 comes with some {@link features/image-upload#official-upload-adapters official upload adapters} but you can also implement your own adapters. +See the "How does the image upload work?" section to learn more + |
+
{@link module:upload/filerepository~UploadAdapter `UploadAdapter`} interface | +
+ An interface defining the minimal API required to create an upload adapter. In other words, it tells you what methods your upload adapter class must have in order wo work. +See "The anatomy of the adapter" section to learn more. + |
+
{@link module:upload/filerepository~FileRepository `FileRepository`} plugin. | +
+ A central point for managing file upload in CKEditor 5. It glues upload adapters and features using them: +
|
+
{@link module:image/imageupload~ImageUpload `ImageUpload`} plugin | +
+ A top–level plugin that responds to actions of the users (e.g. when a file is dropped into the content) by uploading files to the server and updating the edited content once the upload finished. This particular plugin handles user actions related to uploading images. +It uses the See the "How does the image upload work?" section to learn more + |
+