File storage rewrite (#2676)

* Restructure data layer part 2 (#2599)
* Refactor and separate image model
* Refactor image query builder
* Handle relationships in image query builder
* Remove relationship management methods
* Refactor gallery model/query builder
* Add scenes to gallery model
* Convert scene model
* Refactor scene models
* Remove unused methods
* Add unit tests for gallery
* Add image tests
* Add scene tests
* Convert unnecessary scene value pointers to values
* Convert unnecessary pointer values to values
* Refactor scene partial
* Add scene partial tests
* Refactor ImagePartial
* Add image partial tests
* Refactor gallery partial update
* Add partial gallery update tests
* Use zero/null package for null values
* Add files and scan system
* Add sqlite implementation for files/folders
* Add unit tests for files/folders
* Image refactors
* Update image data layer
* Refactor gallery model and creation
* Refactor scene model
* Refactor scenes
* Don't set title from filename
* Allow galleries to freely add/remove images
* Add multiple scene file support to graphql and UI
* Add multiple file support for images in graphql/UI
* Add multiple file for galleries in graphql/UI
* Remove use of some deprecated fields
* Remove scene path usage
* Remove gallery path usage
* Remove path from image
* Move funscript to video file
* Refactor caption detection
* Migrate existing data
* Add post commit/rollback hook system
* Lint. Comment out import/export tests
* Add WithDatabase read only wrapper
* Prepend tasks to list
* Add 32 pre-migration
* Add warnings in release and migration notes

pkg/file/handler.go

@@ -0,0 +1,53 @@
+package file
+
+import (
+	"context"
+	"io/fs"
+)
+
+// PathFilter provides a filter function for paths.
+type PathFilter interface {
+	Accept(ctx context.Context, path string, info fs.FileInfo) bool
+}
+
+type PathFilterFunc func(path string) bool
+
+func (pff PathFilterFunc) Accept(path string) bool {
+	return pff(path)
+}
+
+// Filter provides a filter function for Files.
+type Filter interface {
+	Accept(f File) bool
+}
+
+type FilterFunc func(f File) bool
+
+func (ff FilterFunc) Accept(f File) bool {
+	return ff(f)
+}
+
+// Handler provides a handler for Files.
+type Handler interface {
+	Handle(ctx context.Context, f File) error
+}
+
+// FilteredHandler is a Handler runs only if the filter accepts the file.
+type FilteredHandler struct {
+	Handler
+	Filter
+}
+
+// Handle runs the handler if the filter accepts the file.
+func (h *FilteredHandler) Handle(ctx context.Context, f File) error {
+	if h.Accept(f) {
+		return h.Handler.Handle(ctx, f)
+	}
+	return nil
+}
+
+// CleanHandler provides a handler for cleaning Files and Folders.
+type CleanHandler interface {
+	HandleFile(ctx context.Context, fileDeleter *Deleter, fileID ID) error
+	HandleFolder(ctx context.Context, fileDeleter *Deleter, folderID FolderID) error
+}