(core) Reduce a few log levels to warning

Summary: Reduces the log level in a few places from error to warning.

Test Plan: N/A

Reviewers: paulfitz

Reviewed By: paulfitz

Subscribers: paulfitz

Differential Revision: https://phab.getgrist.com/D3437

app/server/lib/DocWorker.ts

@@ -75,7 +75,11 @@ export class DocWorker {
     return res.type('application/x-sqlite3')
       .download(tmpPath, (optStringParam(req.query.title) || docTitle || 'document') + ".grist", async (err: any) => {
         if (err) {
-          log.error(`Download failure for doc ${docId}`, err);
+          if (err.message && /Request aborted/.test(err.message)) {
+            log.warn(`Download request aborted for doc ${docId}`, err);
+          } else {
+            log.error(`Download failure for doc ${docId}`, err);
+          }
         }
         await fse.unlink(tmpPath);
       });

app/server/lib/uploads.ts

@@ -54,7 +54,11 @@ export function addUploadRoute(server: GristServer, expressApp: Application, ...
       res.status(200).send(JSON.stringify(uploadResult));
     } catch (err) {
       req.resume();
-      log.error("Error uploading file", err);
+      if (err.message && /Request aborted/.test(err.message)) {
+        log.warn("File upload request aborted", err);
+      } else {
+        log.error("Error uploading file", err);
+      }
       // Respond with a JSON error like jsonErrorHandler does for API calls,
       // to make it easier for the caller to parse it.
       res.status(err.status || 500).json({error: err.message || 'internal error'});