Unable to flush permissions after upgrading to 2.6.0 from 2.5.7

[muzzwood]

Summary

Unable to flush permissions after upgrading to MODX 2.6 from 2.5.7

Step to reproduce

Upgrade to 2.6 then try to flush your permissions in the manager.

Observed behavior

Browser gets an empty response from the processor and error in console is: SyntaxError: JSON.parse: unexpected end of data at line 1 column 1 of the JSON data

Expected behavior

Permissions should flush.

Environment

MODX 2.6.0, PHP 7.1

[muzzwood]

https://github.com/modxcms/revolution/blob/2.x/core/model/modx/processors/security/access/flush.class.php#L14

Line 14 in the link above is returning false.

[muzzwood]

https://github.com/modxcms/revolution/blob/2.x/core/model/modx/modcachemanager.class.php#L772

Line 772 in modCacheManager is what's failing.

The contents of the $serialized variable in the line above (771) is: a:3:{i:0;s:2:"en";i:1;s:3:"mgr";i:2;s:3:"web";}

[OptimusCrime]

If it is failing, do you have anything in your error log?

Edit: MODX error log or PHP error log, that is.

[muzzwood]

Nothing in either frustratingly. (MODX log level also set to 4) I tracked the above by using modx->log() at each line to see exactly where it was going wrong.

[muzzwood]

Also can confirm it's happening on more than one install. Both fresh 2.6 install and upgraded from 2.5.7/2.5.8. Also different environments: local as well as remote server.

[OptimusCrime]

MySQL version?

[muzzwood]

One environment is MySQL 5.6.37 another is MySQL 5.7.17

[Bruno17]

maybe it was introduced with this commit? https://github.com/modxcms/revolution/commit/ecc1b0d00bd01ff6d94aa4a830e771a8425185eb#diff-7815df8a113600b79e256c26e16369cf

return false instaed of $this->modx->error->success('');