Httpjson input: Allow specifying POST JSON body

[stanch]

It would be convenient to be able to specify JSON body for POST requests. I guess just providing JSON as a string works, but if it is to be separated by keys, non-string values should be supported (unlike with the GET parameters).

[sparrc]

sure, could you separate this into two separate issues though?

[stanch]

Done!

[guige]

How can input body for http request. I had input body from readme example, but return error.

[danielnelson]

@guige We try to reserve GitHub Issues for actionable bug reports or feature requests. Please ask general questions at the InfluxData Community site.

[guige]

@danielnelson I resove it use httpjson, because i use httprespose.😭

[nmjensen]

This feature would be very useful. I've currently worked around it by calling curl from the exec plugin, but as I'm running Telegraf in the alpine based docker image - it doesn't include curl so I need to install it using apk whenever it's updated.