fix: log missing user at warn level (#3735)

When using PATs if the user that the PAT is for has been removed, we
currently log the missing user at ERROR level. Since this is not
something our SREs can fix, this PR downgrades the NotFoundError to
WARN, instead of ERROR.

src/lib/middleware/pat-middleware.test.ts

@@ -1,6 +1,7 @@
 import getLogger from '../../test/fixtures/no-logger';
 import patMiddleware from './pat-middleware';
 import User from '../types/user';
+import NotFoundError from '../error/notfound-error';
 
 let config: any;
 
@@ -108,3 +109,37 @@ test('should call next if accountService throws exception', async () => {
     expect(cb).toHaveBeenCalled();
     getLogger.setMuteError(false);
 });
+
+test('Should not log at error level if user not found', async () => {
+    let fakeLogger = {
+        debug: () => {},
+        info: () => {},
+        warn: jest.fn(),
+        error: jest.fn(),
+        fatal: console.error,
+    };
+    const conf = {
+        getLogger: () => {
+            return fakeLogger;
+        },
+        flagResolver: {
+            isEnabled: jest.fn().mockReturnValue(true),
+        },
+    };
+    const accountService = {
+        getAccountByPersonalAccessToken: jest.fn().mockImplementation(() => {
+            throw new NotFoundError('Could not find pat');
+        }),
+    };
+    let mw = patMiddleware(conf, { accountService });
+    const cb = jest.fn();
+
+    const req = {
+        header: jest.fn().mockReturnValue('user:some-token'),
+        user: undefined,
+    };
+
+    await mw(req, undefined, cb);
+    expect(fakeLogger.error).not.toHaveBeenCalled();
+    expect(fakeLogger.warn).toHaveBeenCalled();
+});

src/lib/middleware/pat-middleware.ts

@@ -1,5 +1,6 @@
 import { IUnleashConfig } from '../types';
 import { IAuthRequest } from '../routes/unleash-types';
+import NotFoundError from '../error/notfound-error';
 
 /* eslint-disable @typescript-eslint/explicit-module-boundary-types */
 const patMiddleware = (
@@ -21,7 +22,14 @@ const patMiddleware = (
                 accountService.addPATSeen(apiToken);
             }
         } catch (error) {
-            logger.error(error);
+            if (error instanceof NotFoundError) {
+                logger.warn(
+                    'Tried to use a PAT token for user that no longer existed',
+                    error,
+                );
+            } else {
+                logger.error(error);
+            }
         }
         next();
     };