chore: Fix minor code smells

Author: Acconut

cmd/tusd/cli/composer.go

@@ -125,7 +125,7 @@ func CreateComposer() {
 
 		azService, err := azurestore.NewAzureService(azConfig)
 		if err != nil {
-			stderr.Fatalf(err.Error())
+			stderr.Fatalf("Unable to create Azure BlockBlob Storage service: %s", err)
 		}
 
 		store := azurestore.New(azService)

cmd/tusd/cli/flags.go

@@ -205,7 +205,9 @@ func ParseFlags() {
 		f.DurationVar(&Flags.GracefulRequestCompletionTimeout, "request-completion-timeout", 10*time.Second, "Period after which all request operations are cancelled when the request is stopped by the client.")
 	})
 
-	fs.Parse()
+	if err := fs.Parse(); err != nil {
+		stderr.Fatalf("Failed to parse flags: %s", err)
+	}
 
 	SetEnabledHooks()
 

pkg/handler/unrouted_handler.go

@@ -1103,7 +1103,10 @@ func (handler *UnroutedHandler) GetFile(w http.ResponseWriter, r *http.Request)
 	}
 
 	handler.sendResp(c, resp)
-	io.Copy(w, src)
+	if _, err := io.Copy(w, src); err != nil {
+		handler.sendError(c, err)
+		return
+	}
 
 	src.Close()
 }

pkg/hooks/grpc/grpc.go

@@ -79,7 +79,7 @@ func (g *GrpcHook) Setup() error {
 	}
 	grpcOpts = append(grpcOpts, grpc.WithUnaryInterceptor(grpc_retry.UnaryClientInterceptor(opts...)))
 
-	conn, err := grpc.Dial(g.Endpoint, grpcOpts...)
+	conn, err := grpc.NewClient(g.Endpoint, grpcOpts...)
 	if err != nil {
 		return err
 	}

pkg/hooks/hooks_test.go

@@ -180,6 +180,7 @@ func TestNewHandlerWithHooks(t *testing.T) {
 			},
 		},
 	}, err)
+	a.Equal(handler.HTTPResponse{}, resp_got)
 
 	// Successful post-* hooks
 	uploadHandler.CreatedUploads <- event

pkg/s3store/s3store.go

@@ -952,7 +952,9 @@ func (upload *s3Upload) concatUsingDownload(ctx context.Context, partialUploads
 	}
 
 	// Seek to the beginning of the file, so the entire file is being uploaded
-	file.Seek(0, 0)
+	if _, err := file.Seek(0, 0); err != nil {
+		return err
+	}
 
 	// Upload the entire file to S3
 	_, err = store.Service.PutObject(ctx, &s3.PutObjectInput{

pkg/s3store/s3store_part_producer.go

@@ -109,7 +109,10 @@ func (spp *s3PartProducer) nextPart(size int64) (fileChunk, bool, error) {
 		spp.diskWriteDurationMetric.Observe(ms)
 
 		// Seek to the beginning of the file
-		file.Seek(0, 0)
+		if _, err := file.Seek(0, 0); err != nil {
+			cleanUpTempFile(file)
+			return fileChunk{}, false, err
+		}
 
 		return fileChunk{
 			reader: file,