OK as Flic support failed to respond to my emails and haven't been much help generally I ended up turning to Global Cache support and they solved the issue for me. I thought it might be helpful to someone else if I posted the solution. This may also work for other http requests using JSON.
So if you have the IR code for a device and function then this can easily be added as an http request within the Flic app. First you need the code to be in JSON format. The best way to do this is with iLearn which is available for Windows and Mac. The Mac version isn't an official application from Global Cache but a third party. However it works well as I am a Mac only user.
In my case the JSON code for the IR commands was:
{"frequency":38095,"irCode":"342,171,22,21,21,22,21,21,22,21,22,21,21,21,22,21,22,21,21,21,22,21,22,21,22,21,21,64,21,21,22,21,22,21,21,21,22,63,22,63,22,21,22,63,22,21,21,21,22,21,22,63,22,21,22,21,21,64,21,21,22,63,22,63,22,63,22,1829,342,85,21,3661,342,85,22,3660,342,85,22,3660,342,85,22,3809","preamble":"","repeat":1}
So once you have this then go into the Flic app, select which button function you want to assign and select HTTP REQUEST. In the URL field, enter the IP address of your unit followed by the send IR api:
http://[ip address of your unit]/api/v1/irports/[port number]/sendir
You need to make sure you enter the correct ir port number. If you have the tri IR lead connected to a Global Cache Flex then the port numbers are 1,2 & 3. The IR emitters should also be labelled. So if the device you're looking to control has emitter 1 connected to it, then enter:
http://[ip address of your unit]/api/v1/irports/1/sendir
Then ensure you select POST as the method for sending the packet.
In Content Type enter:
application/json
Under Body paste in the IR code in JSON format. It must be enclosed within {}. iLearn will do this automatically for you so it's just a matter of copying and pasting.
Click Done to ensure the entry is saved and it should now work.
I hope this helps someone else and I hope that Flic Support takes note of their poor levels of response and technical support. I'm a Kickstarter backer and think the new hub and buttons are excellent. I couldn't be happier with the hardware but please improve your technical support or at the very least have more documentation for http requests through Flic. For me it's pretty much all I'm using the hub for as most of my devices aren't natively listed and I therefore need to send http api commands for what I want to control.
