Using headers in webhook parameters

[lukepearcewp]

I was struggling trying to get the X-Origin-Url into a parameter - here's a few options incase this helps someone else (and if there's a better way I'd love to know):

Use dig with a default value:

dataTemplate: "{{ dig \"header\" \"X-Origin-Url\" (list \"https://hello.world\") .Input | first }}"

Use dig but rely on the usual parameter default value key:

dataTemplate: "{{ dig \"header\" \"X-Origin-Url\" (list \"\") .Input | first }}"
value: https://hello.world/

Using get:

dataTemplate: "{{ get (get .Input \"header\") \"X-Origin-Url\" | first }}"
value: https://hello.world/

Notes:

• You need to supply a default value or if the header is missing/blank you'll end up with the whole event json headers & body as the parameter value which is probably not what you want.
• You only need to use dig/get to extract the header when it contains dashes. This isn't required for say header.Accept, but you will still need to use dataTemplate e.g. dataTemplate: "{{ .Input.header.Accept }}"
• It appears the header values are returned as arrays rather than strings hence the | first to return the string value.