api/worker: adjust error codes in postLayer

api/v1/routes.go

@@ -110,20 +110,14 @@ func postLayer(w http.ResponseWriter, r *http.Request, p httprouter.Params, ctx
 
 	err = worker.Process(ctx.Store, request.Layer.Name, request.Layer.ParentName, request.Layer.Path, request.Layer.Format)
 	if err != nil {
-		if err == cerrors.ErrNotFound || err == worker.ErrParentUnknown {
-			writeResponse(w, r, http.StatusNotFound, LayerEnvelope{Error: &Error{err.Error()}})
-			return postLayerRoute, http.StatusNotFound
-		}
-
 		if err == utils.ErrCouldNotExtract ||
 			err == utils.ErrExtractedFileTooBig ||
 			err == worker.ErrUnsupported {
 			writeResponse(w, r, statusUnprocessableEntity, LayerEnvelope{Error: &Error{err.Error()}})
 			return postLayerRoute, statusUnprocessableEntity
 		}
 
-		_, badreq := err.(*cerrors.ErrBadRequest)
-		if badreq || err == utils.ErrCouldNotExtract || err == utils.ErrExtractedFileTooBig {
+		if _, badreq := err.(*cerrors.ErrBadRequest); badreq {
 			writeResponse(w, r, http.StatusBadRequest, LayerEnvelope{Error: &Error{err.Error()}})
 			return postLayerRoute, http.StatusBadRequest
 		}

worker/detectors/data.go

@@ -42,6 +42,9 @@ var (
 	dataDetectors     = make(map[string]DataDetector)
 
 	log = capnslog.NewPackageLogger("github.com/coreos/clair", "detectors")
+
+	// ErrCouldNotFindLayer is returned when we could not download or open the layer file.
+	ErrCouldNotFindLayer = cerrors.NewBadRequestError("could not find layer")
 )
 
 // RegisterDataDetector provides a way to dynamically register an implementation of a
@@ -73,20 +76,17 @@ func DetectData(path string, format string, toExtract []string, maxFileSize int6
 		r, err := http.Get(path)
 		if err != nil {
 			log.Warningf("could not download layer: %s", err)
-			return nil, cerrors.ErrCouldNotDownload
-		}
-		if r.StatusCode == 404 {
-			return nil, cerrors.ErrNotFound
+			return nil, ErrCouldNotFindLayer
 		}
 		if math.Floor(float64(r.StatusCode/100)) != 2 {
 			log.Warningf("could not download layer: got status code %d, expected 2XX", r.StatusCode)
-			return nil, cerrors.ErrCouldNotDownload
+			return nil, ErrCouldNotFindLayer
 		}
 		layerReader = r.Body
 	} else {
 		layerReader, err = os.Open(path)
 		if err != nil {
-			return nil, cerrors.ErrNotFound
+			return nil, ErrCouldNotFindLayer
 		}
 	}
 	defer layerReader.Close()