Nitromelon

1. Check the error log to see if there is connection issue. 2. Add timeout for sql query in db_clients config, and try again.

Why it is unnecessary ? If we use "visitDate" everywhere in the code, it becomes an error-prone magic string.

I wish I could scroll the session window when I drag session entry accross folders. Sometimes the imported sessions is way down below that I can not drag them to...

This PR is suspended for the following reason: `DbGeneralConfig` is not a elegant solution. We have three types of database, but each one would only use some of the fields....

> put config to std::variant . how about ? > > ``` > auto createDbClient(std::variant config) { > } > ``` I will give it a try

Use std::variant. Next we should update the `DbClient::newXxxClient()` and `DbClientLockFree` api. Or, we could wait.

Not familiar with video processing. But sounds like you need tcp/udp to do the job? Drogon provides tcp client/server, but no udp support for now.

Code in `RealIpResolver::matchCidr()` can be reused here.

在drogon这侧没有任何头绪...

I don't think we need this...