Convert multipart form into JSON

Webhook Relay detects multipart/formdata requests and automatically parses them so your function can use it. Parsed form data can be accessed through r.RequestFormData variable. You can use Webhook Relay to receive a form and convert it into any kind of JSON that can be sent to another API.

For example if the payload fragment looks like this:

...
--------------------------5683f7544dff7b07
Content-Disposition: form-data; name="username"

John
--------------------------5683f7544dff7b07
...

Then to get username value (which is John) you will need to:

-- import "json" package when working with JSON
local json = require("json")

-- values can be accessed through 'r.RequestFormData' object. Since 
-- there can be multiple values for each key, you also need to 
-- specify that it's the first element of the list:
local username = r.RequestFormData.username[1]
local first_name = r.RequestFormData.first_name[1]

-- transforming form data into JSON
local json_payload = {
  username = username,
  first_name = first_name
}

local encoded_payload, err = json.encode(json_payload)
if err then error(err) end

r:SetRequestBody(encoded_payload)

For the decoding to work, Webhook Relay expects a header Content-Type that includes multipart/form-data and the boundary.