phabircator files error

phabricator_error.log

[Thu Sep 05 13:30:07.808379 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362] [2019-09-05 13:30:07] EXCEPTION: (Exception) HMAC-SHA256 can only digest strings. at [<phabricator>/src/infrastructure/util/PhabricatorHash.php:191]
[Thu Sep 05 13:30:07.809319 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362] arcanist(head=stable, ref.master=25c2381959ac, ref.stable=feb5f4d42c4f), phabricator(head=stable, ref.master=187356fea515, ref.stable=0c3f59fd688a), phutil(head=stable, ref.master=f430af3cd431, ref.stable=794ded985711)
[Thu Sep 05 13:30:07.809340 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #0 <#2> PhabricatorHash::digestHMACSHA256(NULL, string) called at [<phabricator>/src/infrastructure/util/PhabricatorHash.php:186]
[Thu Sep 05 13:30:07.809346 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #1 <#2> PhabricatorHash::digestWithNamedKey(NULL, string) called at [<phabricator>/src/applications/files/engine/PhabricatorFileStorageEngine.php:374]
[Thu Sep 05 13:30:07.809351 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #2 <#2> PhabricatorFileStorageEngine::newIntegrityHash(NULL, PhabricatorFileRawStorageFormat) called at [<phabricator>/src/applications/files/engine/PhabricatorFileStorageEngine.php:340]
[Thu Sep 05 13:30:07.809356 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #3 <#2> PhabricatorFileStorageEngine::getRawFileDataIterator(PhabricatorFile, NULL, integer, PhabricatorFileRawStorageFormat) called at [<phabricator>/src/applications/files/storage/PhabricatorFile.php:818]
[Thu Sep 05 13:30:07.809426 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #4 <#2> PhabricatorFile::getFileDataIterator(NULL, integer) called at [<phabricator>/src/applications/files/document/PhabricatorDocumentRef.php:77]
[Thu Sep 05 13:30:07.809432 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #5 <#2> PhabricatorDocumentRef::loadData(NULL, integer) called at [<phabricator>/src/applications/files/document/PhabricatorDocumentRef.php:143]
[Thu Sep 05 13:30:07.809437 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #6 <#2> PhabricatorDocumentRef::getSnippet() called at [<phabricator>/src/applications/files/document/PhabricatorDocumentRef.php:112]
[Thu Sep 05 13:30:07.809442 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #7 <#2> PhabricatorDocumentRef::isProbablyText() called at [<phabricator>/src/applications/files/document/PhabricatorDocumentRef.php:117]
[Thu Sep 05 13:30:07.809447 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #8 <#2> PhabricatorDocumentRef::isProbablyJSON() called at [<phabricator>/src/applications/files/document/PhabricatorJupyterDocumentEngine.php:35]
[Thu Sep 05 13:30:07.809452 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #9 <#2> PhabricatorJupyterDocumentEngine::canRenderDocumentType(PhabricatorDocumentRef) called at [<phabricator>/src/applications/files/document/PhabricatorDocumentEngine.php:31]
[Thu Sep 05 13:30:07.809457 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #10 <#2> PhabricatorDocumentEngine::canRenderDocument(PhabricatorDocumentRef) called at [<phabricator>/src/applications/files/document/PhabricatorDocumentEngine.php:182]
[Thu Sep 05 13:30:07.809462 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #11 <#2> PhabricatorDocumentEngine::getEnginesForRef(PhabricatorUser, PhabricatorDocumentRef) called at [<phabricator>/src/applications/files/document/render/PhabricatorDocumentRenderingEngine.php:49]
[Thu Sep 05 13:30:07.809468 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #12 <#2> PhabricatorDocumentRenderingEngine::newDocumentView(PhabricatorDocumentRef) called at [<phabricator>/src/applications/files/controller/PhabricatorFileViewController.php:414]
[Thu Sep 05 13:30:07.809473 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #13 <#2> PhabricatorFileViewController::newFileContent(PhabricatorFile) called at [<phabricator>/src/applications/files/controller/PhabricatorFileViewController.php:77]
[Thu Sep 05 13:30:07.809478 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #14 <#2> PhabricatorFileViewController::handleRequest(AphrontRequest) called at [<phabricator>/src/aphront/configuration/AphrontApplicationConfiguration.php:286]
[Thu Sep 05 13:30:07.809495 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #15 phlog(Exception) called at [<phabricator>/src/aphront/handler/PhabricatorDefaultRequestExceptionHandler.php:41]
[Thu Sep 05 13:30:07.809500 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #16 PhabricatorDefaultRequestExceptionHandler::handleRequestThrowable(AphrontRequest, Exception) called at [<phabricator>/src/aphront/configuration/AphrontApplicationConfiguration.php:750]
[Thu Sep 05 13:30:07.809505 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #17 AphrontApplicationConfiguration::handleThrowable(Exception) called at [<phabricator>/src/aphront/configuration/AphrontApplicationConfiguration.php:298]
[Thu Sep 05 13:30:07.809509 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #18 AphrontApplicationConfiguration::processRequest(AphrontRequest, PhutilDeferredLog, AphrontPHPHTTPSink, MultimeterControl) called at [<phabricator>/src/aphront/configuration/AphrontApplicationConfiguration.php:209]
[Thu Sep 05 13:30:07.809514 2019] [php7:notice] [pid 17636] [client 192.168.100.7:49362]   #19 AphrontApplicationConfiguration::runHTTPRequest(AphrontPHPHTTPSink) called at [<phabricator>/webroot/index.php:35]