[Solved] Mobile file upload fails

Troubleshooting Mobile Apps
1

Hi all,
I have just installed the community edition on my own server.
The system works greate - besides from one thing:
When I try to upload any files, pictures or anything from a mobile device, I get the error:
“JSON could not be serialized because of error:”

I have tested both iOS and Android mobile clients.
The server version is 10.1.1 and the iOS version is 2.21.0. Not sure about the Android version.

Any hints to what can be wrong ?

2

It works fine in the computer apps, tested on MacOS Sequoia 15.0.1 and Ubuntu Linux 24.10.

3

Does /opt/mattermost/logs/mattermost.log say anything?

4

It logs a lot of things, but nothing related to the file upload.
I turned up the logging level to debug level and watched the log using tail -f, but nothing was logged when trying the file upload.
I noticed a couple of parameters in the confog.json file for MaxFileSize anf MaxResolution, and I’ve tried to increase those.
But I’m not sure this actually helps. I need to do some more testing.

5

When restarting the mattermost server (systemctl restart mattermost), the log file gives me a hint:
{"timestamp":"2024-10-27 10:05:16.677 +01:00","level":"info","msg":"Post.Message has size restrictions","caller":"sqlstore/post_store.go:2615","max_characters":16383,"max_bytes":65535}
I’m using a postgres backend. Can this be the issue ?

6

And I think I now have found my problem source:
I increased the client_max_body_size parameter in the nginx proxy server in front of mattermost.
When using the client applications on my network, I didn’t use the proxy, and that’s why I had no problems with the local application.

1 Like
7

Thanks so much for following up with the solution, Johan! Glad to hear you were able to get it working.

8

I run Mattermost enterprise at work, and this problem was with my own, privately hosted opensource edition. I am actively erasing telgram for my communications issues. And replace it with the fantastic Mattermost application.

1 Like