[MM-26812] Add support for resumable file uploads (#15252)

* Implement AppendFile for FileBackend

* Split test into subtests

* [MM-26812] Add support for resumable file uploads (#15252)

* Implement UploadSession

* Implement UploadSessionStore

* Add error strings

* Implement resumable file uploads

* Add UploadType

* Fix retry layer tests

* Regenerate store layers

* Fix store error handling

* Use base for filename

* Prevent concurrent uploads on the same upload session

* Fix erroneus error string

* Improve error handling

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

* Fix translations

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

web/context.go

@@ -386,6 +386,18 @@ func (c *Context) RequireFileId() *Context {
 	return c
 }
 
+func (c *Context) RequireUploadId() *Context {
+	if c.Err != nil {
+		return c
+	}
+
+	if !model.IsValidId(c.Params.UploadId) {
+		c.SetInvalidUrlParam("upload_id")
+	}
+
+	return c
+}
+
 func (c *Context) RequireFilename() *Context {
 	if c.Err != nil {
 		return c

web/params.go

@@ -31,6 +31,7 @@ type Params struct {
 	PostId                    string
 	FileId                    string
 	Filename                  string
+	UploadId                  string
 	PluginId                  string
 	CommandId                 string
 	HookId                    string
@@ -123,6 +124,10 @@ func ParamsFromRequest(r *http.Request) *Params {
 
 	params.Filename = query.Get("filename")
 
+	if val, ok := props["upload_id"]; ok {
+		params.UploadId = val
+	}
+
 	if val, ok := props["plugin_id"]; ok {
 		params.PluginId = val
 	}