KEY insight to making mqtt work correctly for weewx-belchertown!

[MrPeteH]

I was tearing out what little hair remains, trying to get the Belchertown mqtt connection to function. Then I realized the following:

• We enter the mqtt belchertown client config info into the computer that's running weewx
• That configuration is auto-uploaded to the web server hosting the belchertown-based website
• THAT server then downloads the config, together with other code, as javascript running in a person's web browser (whether on a phone, tablet, desktop, etc)

Result: the access information in belchertown needs to be from the perspective of the web browser... NOT weewx, and NOT the website host!

In general, this means:

• You need a subdomain name for the mqtt broker computer, with a DNS A record (ie public IP address)
• When accessing that name from the local network where the broker runs, the local DNS probably needs to provide the correct LAN IP address

Once I had that, and had the current master.zip version of belchertown, all was well. (The current old release is broken.)