Return `null` if MaxFileSizeBytes is 0 (#2409)

* Return "null" if MaxFileSizeBytes is 0

* Add comment and nil check (better save than sorry)

* Simplify config

4 files changed, 18 insertions, 15 deletions

diff --git a/mediaapi/routing/download.go b/mediaapi/routing/download.go
index 5f22a946..10b25a5c 100644
--- a/mediaapi/routing/download.go
+++ b/mediaapi/routing/download.go
@@ -551,7 +551,7 @@ func (r *downloadRequest) getRemoteFile(
 			// If we do not have a record, we need to fetch the remote file first and then respond from the local file
 			err := r.fetchRemoteFileAndStoreMetadata(
 				ctx, client,
-				cfg.AbsBasePath, *cfg.MaxFileSizeBytes, db,
+				cfg.AbsBasePath, cfg.MaxFileSizeBytes, db,
 				cfg.ThumbnailSizes, activeThumbnailGeneration,
 				cfg.MaxThumbnailGenerators,
 			)
diff --git a/mediaapi/routing/routing.go b/mediaapi/routing/routing.go
index 0e158399..97dfd334 100644
--- a/mediaapi/routing/routing.go
+++ b/mediaapi/routing/routing.go
@@ -35,7 +35,7 @@ import (
 // configResponse is the response to GET /_matrix/media/r0/config
 // https://matrix.org/docs/spec/client_server/latest#get-matrix-media-r0-config
 type configResponse struct {
-	UploadSize config.FileSizeBytes `json:"m.upload.size"`
+	UploadSize *config.FileSizeBytes `json:"m.upload.size"`
 }
 
 // Setup registers the media API HTTP handlers
@@ -73,9 +73,13 @@ func Setup(
 		if r := rateLimits.Limit(req); r != nil {
 			return *r
 		}
+		respondSize := &cfg.MaxFileSizeBytes
+		if cfg.MaxFileSizeBytes == 0 {
+			respondSize = nil
+		}
 		return util.JSONResponse{
 			Code: http.StatusOK,
-			JSON: configResponse{UploadSize: *cfg.MaxFileSizeBytes},
+			JSON: configResponse{UploadSize: respondSize},
 		}
 	})
 
diff --git a/mediaapi/routing/upload.go b/mediaapi/routing/upload.go
index 972c52af..2175648e 100644
--- a/mediaapi/routing/upload.go
+++ b/mediaapi/routing/upload.go
@@ -90,7 +90,7 @@ func parseAndValidateRequest(req *http.Request, cfg *config.MediaAPI, dev *usera
 		Logger: util.GetLogger(req.Context()).WithField("Origin", cfg.Matrix.ServerName),
 	}
 
-	if resErr := r.Validate(*cfg.MaxFileSizeBytes); resErr != nil {
+	if resErr := r.Validate(cfg.MaxFileSizeBytes); resErr != nil {
 		return nil, resErr
 	}
 
@@ -148,20 +148,20 @@ func (r *uploadRequest) doUpload(
 	//   r.storeFileAndMetadata(ctx, tmpDir, ...)
 	// before you return from doUpload else we will leak a temp file. We could make this nicer with a `WithTransaction` style of
 	// nested function to guarantee either storage or cleanup.
-	if *cfg.MaxFileSizeBytes > 0 {
-		if *cfg.MaxFileSizeBytes+1 <= 0 {
+	if cfg.MaxFileSizeBytes > 0 {
+		if cfg.MaxFileSizeBytes+1 <= 0 {
 			r.Logger.WithFields(log.Fields{
-				"MaxFileSizeBytes": *cfg.MaxFileSizeBytes,
+				"MaxFileSizeBytes": cfg.MaxFileSizeBytes,
 			}).Warnf("Configured MaxFileSizeBytes overflows int64, defaulting to %d bytes", config.DefaultMaxFileSizeBytes)
-			cfg.MaxFileSizeBytes = &config.DefaultMaxFileSizeBytes
+			cfg.MaxFileSizeBytes = config.DefaultMaxFileSizeBytes
 		}
-		reqReader = io.LimitReader(reqReader, int64(*cfg.MaxFileSizeBytes)+1)
+		reqReader = io.LimitReader(reqReader, int64(cfg.MaxFileSizeBytes)+1)
 	}
 
 	hash, bytesWritten, tmpDir, err := fileutils.WriteTempFile(ctx, reqReader, cfg.AbsBasePath)
 	if err != nil {
 		r.Logger.WithError(err).WithFields(log.Fields{
-			"MaxFileSizeBytes": *cfg.MaxFileSizeBytes,
+			"MaxFileSizeBytes": cfg.MaxFileSizeBytes,
 		}).Warn("Error while transferring file")
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
@@ -170,9 +170,9 @@ func (r *uploadRequest) doUpload(
 	}
 
 	// Check if temp file size exceeds max file size configuration
-	if *cfg.MaxFileSizeBytes > 0 && bytesWritten > types.FileSizeBytes(*cfg.MaxFileSizeBytes) {
+	if cfg.MaxFileSizeBytes > 0 && bytesWritten > types.FileSizeBytes(cfg.MaxFileSizeBytes) {
 		fileutils.RemoveDir(tmpDir, r.Logger) // delete temp file
-		return requestEntityTooLargeJSONResponse(*cfg.MaxFileSizeBytes)
+		return requestEntityTooLargeJSONResponse(cfg.MaxFileSizeBytes)
 	}
 
 	// Look up the media by the file hash. If we already have the file but under a
diff --git a/mediaapi/routing/upload_test.go b/mediaapi/routing/upload_test.go
index b2c2f5a4..e04c010f 100644
--- a/mediaapi/routing/upload_test.go
+++ b/mediaapi/routing/upload_test.go
@@ -36,12 +36,11 @@ func Test_uploadRequest_doUpload(t *testing.T) {
 	}
 
 	maxSize := config.FileSizeBytes(8)
-	unlimitedSize := config.FileSizeBytes(0)
 	logger := log.New().WithField("mediaapi", "test")
 	testdataPath := filepath.Join(wd, "./testdata")
 
 	cfg := &config.MediaAPI{
-		MaxFileSizeBytes:  &maxSize,
+		MaxFileSizeBytes:  maxSize,
 		BasePath:          config.Path(testdataPath),
 		AbsBasePath:       config.Path(testdataPath),
 		DynamicThumbnails: false,
@@ -124,7 +123,7 @@ func Test_uploadRequest_doUpload(t *testing.T) {
 				ctx:       context.Background(),
 				reqReader: strings.NewReader("test test test"),
 				cfg: &config.MediaAPI{
-					MaxFileSizeBytes:  &unlimitedSize,
+					MaxFileSizeBytes:  config.FileSizeBytes(0),
 					BasePath:          config.Path(testdataPath),
 					AbsBasePath:       config.Path(testdataPath),
 					DynamicThumbnails: false,