[MM-42194] Get file information from a deleted post (#20279)

* Introduced inlcude_deleted query parameter to allow admins to retrieve contents of post regardless of deletion status

* Introduced new client route and tests for getting file info of deleted posts

* Fixed tests due to caching of posts

* gofmt

* Small formatting updates

* Invalidating file infos cache on delete of post if post includes files

* Including deleted in migration flow

* Moved invalidating of cache

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

api4/post.go

@@ -898,7 +898,13 @@ func getFileInfosForPost(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	infos, err := c.App.GetFileInfosForPostWithMigration(c.Params.PostId)
+	includeDeleted, _ := strconv.ParseBool(r.URL.Query().Get("include_deleted"))
+	if includeDeleted && !c.App.SessionHasPermissionTo(*c.AppContext.Session(), model.PermissionManageSystem) {
+		c.SetPermissionError(model.PermissionManageSystem)
+		return
+	}
+
+	infos, err := c.App.GetFileInfosForPostWithMigration(c.Params.PostId, includeDeleted)
 	if err != nil {
 		c.Err = err
 		return

api4/post_test.go

@@ -2623,6 +2623,39 @@ func TestGetFileInfosForPost(t *testing.T) {
 	require.Error(t, err)
 	CheckForbiddenStatus(t, resp)
 
+	// Delete post
+	th.SystemAdminClient.DeletePost(post.Id)
+
+	// Normal client should get 404 when trying to access deleted post normally
+	_, resp, err = client.GetFileInfosForPost(post.Id, "")
+	require.Error(t, err)
+	CheckNotFoundStatus(t, resp)
+
+	// Normal client should get unauthorized when trying to access deleted post
+	_, resp, err = client.GetFileInfosForPostIncludeDeleted(post.Id, "")
+	require.Error(t, err)
+	CheckForbiddenStatus(t, resp)
+
+	// System client should get 404 when trying to access deleted post normally
+	_, resp, err = th.SystemAdminClient.GetFileInfosForPost(post.Id, "")
+	require.Error(t, err)
+	CheckNotFoundStatus(t, resp)
+
+	// System client should be able to access deleted post with include_deleted param
+	infos, _, err = th.SystemAdminClient.GetFileInfosForPostIncludeDeleted(post.Id, "")
+	require.NoError(t, err)
+
+	require.Len(t, infos, 3, "missing file infos")
+
+	found = false
+	for _, info := range infos {
+		if info.Id == fileIds[0] {
+			found = true
+		}
+	}
+
+	require.True(t, found, "missing file info")
+
 	client.Logout()
 	_, resp, err = client.GetFileInfosForPost(model.NewId(), "")
 	require.Error(t, err)

app/app_iface.go

@@ -630,8 +630,8 @@ type AppIface interface {
 	GetFile(fileID string) ([]byte, *model.AppError)
 	GetFileInfo(fileID string) (*model.FileInfo, *model.AppError)
 	GetFileInfos(page, perPage int, opt *model.GetFileInfosOptions) ([]*model.FileInfo, *model.AppError)
-	GetFileInfosForPost(postID string, fromMaster bool) ([]*model.FileInfo, *model.AppError)
-	GetFileInfosForPostWithMigration(postID string) ([]*model.FileInfo, *model.AppError)
+	GetFileInfosForPost(postID string, fromMaster bool, includeDeleted bool) ([]*model.FileInfo, *model.AppError)
+	GetFileInfosForPostWithMigration(postID string, includeDeleted bool) ([]*model.FileInfo, *model.AppError)
 	GetFlaggedPosts(userID string, offset int, limit int) (*model.PostList, *model.AppError)
 	GetFlaggedPostsForChannel(userID, channelID string, offset int, limit int) (*model.PostList, *model.AppError)
 	GetFlaggedPostsForTeam(userID, teamID string, offset int, limit int) (*model.PostList, *model.AppError)

app/import_functions.go

@@ -1224,7 +1224,7 @@ func (a *App) importAttachment(c *request.Context, data *AttachmentImportData, p
 
 	// Go over existing files in the post and see if there already exists a file with the same name, size and hash. If so - skip it
 	if post.Id != "" {
-		oldFiles, err := a.GetFileInfosForPost(post.Id, true)
+		oldFiles, err := a.GetFileInfosForPost(post.Id, true, false)
 		if err != nil {
 			return nil, model.NewAppError("BulkImport", "app.import.attachment.file_upload.error", map[string]any{"FilePath": *data.Path}, "", http.StatusBadRequest)
 		}

app/opentracing/opentracing_layer.go

@@ -5970,7 +5970,7 @@ func (a *OpenTracingAppLayer) GetFileInfos(page int, perPage int, opt *model.Get
 	return resultVar0, resultVar1
 }
 
-func (a *OpenTracingAppLayer) GetFileInfosForPost(postID string, fromMaster bool) ([]*model.FileInfo, *model.AppError) {
+func (a *OpenTracingAppLayer) GetFileInfosForPost(postID string, fromMaster bool, includeDeleted bool) ([]*model.FileInfo, *model.AppError) {
 	origCtx := a.ctx
 	span, newCtx := tracing.StartSpanWithParentByContext(a.ctx, "app.GetFileInfosForPost")
 
@@ -5982,7 +5982,7 @@ func (a *OpenTracingAppLayer) GetFileInfosForPost(postID string, fromMaster bool
 	}()
 
 	defer span.Finish()
-	resultVar0, resultVar1 := a.app.GetFileInfosForPost(postID, fromMaster)
+	resultVar0, resultVar1 := a.app.GetFileInfosForPost(postID, fromMaster, includeDeleted)
 
 	if resultVar1 != nil {
 		span.LogFields(spanlog.Error(resultVar1))
@@ -5992,7 +5992,7 @@ func (a *OpenTracingAppLayer) GetFileInfosForPost(postID string, fromMaster bool
 	return resultVar0, resultVar1
 }
 
-func (a *OpenTracingAppLayer) GetFileInfosForPostWithMigration(postID string) ([]*model.FileInfo, *model.AppError) {
+func (a *OpenTracingAppLayer) GetFileInfosForPostWithMigration(postID string, includeDeleted bool) ([]*model.FileInfo, *model.AppError) {
 	origCtx := a.ctx
 	span, newCtx := tracing.StartSpanWithParentByContext(a.ctx, "app.GetFileInfosForPostWithMigration")
 
@@ -6004,7 +6004,7 @@ func (a *OpenTracingAppLayer) GetFileInfosForPostWithMigration(postID string) ([
 	}()
 
 	defer span.Finish()
-	resultVar0, resultVar1 := a.app.GetFileInfosForPostWithMigration(postID)
+	resultVar0, resultVar1 := a.app.GetFileInfosForPostWithMigration(postID, includeDeleted)
 
 	if resultVar1 != nil {
 		span.LogFields(spanlog.Error(resultVar1))

app/post.go

@@ -1269,6 +1269,8 @@ func (a *App) DeletePost(c request.CTX, postID, deleteByID string) (*model.Post,
 		a.Srv().Go(func() {
 			a.deletePostFiles(post.Id)
 		})
+		a.Srv().Store.FileInfo().InvalidateFileInfosForPostCache(postID, true)
+		a.Srv().Store.FileInfo().InvalidateFileInfosForPostCache(postID, false)
 	}
 	a.Srv().Go(func() {
 		a.deleteFlaggedPosts(post.Id)
@@ -1541,16 +1543,16 @@ func (a *App) GetRecentSearchesForUser(userID string) ([]*model.SearchParams, *m
 	return searchParams, nil
 }
 
-func (a *App) GetFileInfosForPostWithMigration(postID string) ([]*model.FileInfo, *model.AppError) {
+func (a *App) GetFileInfosForPostWithMigration(postID string, includeDeleted bool) ([]*model.FileInfo, *model.AppError) {
 
 	pchan := make(chan store.StoreResult, 1)
 	go func() {
-		post, err := a.Srv().Store.Post().GetSingle(postID, false)
+		post, err := a.Srv().Store.Post().GetSingle(postID, includeDeleted)
 		pchan <- store.StoreResult{Data: post, NErr: err}
 		close(pchan)
 	}()
 
-	infos, err := a.GetFileInfosForPost(postID, false)
+	infos, err := a.GetFileInfosForPost(postID, false, includeDeleted)
 	if err != nil {
 		return nil, err
 	}
@@ -1580,8 +1582,8 @@ func (a *App) GetFileInfosForPostWithMigration(postID string) ([]*model.FileInfo
 	return infos, nil
 }
 
-func (a *App) GetFileInfosForPost(postID string, fromMaster bool) ([]*model.FileInfo, *model.AppError) {
-	fileInfos, err := a.Srv().Store.FileInfo().GetForPost(postID, fromMaster, false, true)
+func (a *App) GetFileInfosForPost(postID string, fromMaster bool, includeDeleted bool) ([]*model.FileInfo, *model.AppError) {
+	fileInfos, err := a.Srv().Store.FileInfo().GetForPost(postID, fromMaster, includeDeleted, true)
 	if err != nil {
 		return nil, model.NewAppError("GetFileInfosForPost", "app.file_info.get_for_post.app_error", nil, err.Error(), http.StatusInternalServerError)
 	}

app/post_metadata.go

@@ -216,7 +216,7 @@ func (a *App) getFileMetadataForPost(post *model.Post, fromMaster bool) ([]*mode
 		return nil, nil
 	}
 
-	return a.GetFileInfosForPost(post.Id, fromMaster)
+	return a.GetFileInfosForPost(post.Id, fromMaster, false)
 }
 
 func (a *App) getEmojisAndReactionsForPost(post *model.Post) ([]*model.Emoji, []*model.Reaction, *model.AppError) {

app/post_test.go

@@ -219,7 +219,7 @@ func TestAttachFilesToPost(t *testing.T) {
 		appErr := th.App.attachFilesToPost(post)
 		assert.Nil(t, appErr)
 
-		infos, appErr := th.App.GetFileInfosForPost(post.Id, false)
+		infos, appErr := th.App.GetFileInfosForPost(post.Id, false, false)
 		assert.Nil(t, appErr)
 		assert.Len(t, infos, 2)
 	})
@@ -247,7 +247,7 @@ func TestAttachFilesToPost(t *testing.T) {
 		appErr := th.App.attachFilesToPost(post)
 		assert.Nil(t, appErr)
 
-		infos, appErr := th.App.GetFileInfosForPost(post.Id, false)
+		infos, appErr := th.App.GetFileInfosForPost(post.Id, false, false)
 		assert.Nil(t, appErr)
 		assert.Len(t, infos, 1)
 		assert.Equal(t, info2.Id, infos[0].Id)

model/client4.go

@@ -4419,6 +4419,24 @@ func (c *Client4) GetFileInfosForPost(postId string, etag string) ([]*FileInfo,
 	return list, BuildResponse(r), nil
 }
 
+// GetFileInfosForPost gets all the file info objects attached to a post, including deleted
+func (c *Client4) GetFileInfosForPostIncludeDeleted(postId string, etag string) ([]*FileInfo, *Response, error) {
+	r, err := c.DoAPIGet(c.postRoute(postId)+"/files/info"+"?include_deleted="+c.boolString(true), etag)
+	if err != nil {
+		return nil, BuildResponse(r), err
+	}
+	defer closeBody(r)
+
+	var list []*FileInfo
+	if r.StatusCode == http.StatusNotModified {
+		return list, BuildResponse(r), nil
+	}
+	if jsonErr := json.NewDecoder(r.Body).Decode(&list); jsonErr != nil {
+		return nil, nil, NewAppError("GetFileInfosForPostIncludeDeleted", "api.unmarshal_error", nil, jsonErr.Error(), http.StatusInternalServerError)
+	}
+	return list, BuildResponse(r), nil
+}
+
 // General/System Section
 
 // GenerateSupportPacket downloads the generated support packet