Dynmap: Uncaught TypeError: Cannot read property 'length' of null

[Lachney]

jquery-1.11.0.js?_=3.1-SNAPSHOT-408:358 Uncaught TypeError: Cannot read property 'length' of null
    at Function.each (jquery-1.11.0.js?_=3.1-SNAPSHOT-408:358)
    at DynMap.configure (map.js?_=3.1-SNAPSHOT-408:85)
    at map.js?_=3.1-SNAPSHOT-408:37
    at success (jquery.json.js?_=3.1-SNAPSHOT-408:82)
    at Object.obj.success (jquery.json.js?_=3.1-SNAPSHOT-408:19)
    at fire (jquery-1.11.0.js?_=3.1-SNAPSHOT-408:3099)
    at Object.fireWith [as resolveWith] (jquery-1.11.0.js?_=3.1-SNAPSHOT-408:3211)
    at done (jquery-1.11.0.js?_=3.1-SNAPSHOT-408:9310)
    at XMLHttpRequest.callback (jquery-1.11.0.js?_=3.1-SNAPSHOT-408:9720)

Issue Description: I'm trying to setup an external web server using nginx on Ubuntu 20.04. When accessing the map on the browser, it only shows up a black screen. In the console, it outputs the error above. I have checked my folder permissions, seemed all good. I have disabled the internal web server, I am using MySQL for storage and have enabled the "JsonFileClientUpdateComponent" and commented out InternalClientUpdateComponent.

• Dynmap Version: 3.1-beta-3-406
• Server Version: git-Paper-134 (Minecraft 1.16.1)
• Pastebin of Configuration.txt: https://pastebin.com/4Ts36nWA
• Server Host (if applicable): Selfhosted
• Pastebin of crashlogs or other relevant logs: no errors caused by plugin
• Other Relevant Data/Screenshots: I'm using Ubuntu 20.04, PHP 7.4, NGINX 1.18.0

• Steps to Replicate:

  • Disable internal webserver then follow the guide listed here: https://github.com/webbukkit/dynmap/wiki/External-Webserver-Basics

  [X] I have looked at all other issues and this is not a duplicate
  
  [X] I have been able to replicate this

[FedUpWith-Tech]

Related to #3075

[FedUpWith-Tech]

FYI: This issue is as far as I am aware limited to nginx and mysql, apache and other web hosts haven't had this issue as well as other storage options. I know this isn't a great solution and I'm investigating why that specific combo is causing so many issues but there are workarounds available

[Leonardo-Fiori]

And here I am too! Found ya.

Had the brilliant idea to setup an NGINX server for my old Dynmap.
It took me an entire day but at the end I got it working, I had to configure NGINX to use PHP, also.
For an hour or two I was getting "could not retrieve configuration: error" then once i got PHP set up, it disappeared.

All I get now is a black screen and this error in console:

www.peacefulvanilla.club/map.html

I am kinda happy to have found this issue, but also annoyed 😢