Working with JSON

JSON is a popular format in which services exchange information. Functions allow parsing and modifying these payloads to integrate different services with each other.

To decode or encode JSON in a Lua function, import β€˜json’ package:

-- import "json" package when working with JSON
local json = require("json")
​
-- example payload:
-- {
-- "user": "Peter",
-- "age": 25,
-- "city": "Edinburgh"
-- }
​
local request_payload, err = json.decode(r.RequestBody)
if err then error(err) end
​
-- now, request_payload is a normal JSON object and we
-- can access individual values
​
r:SetRequestBody(request_payload.user)
-- request will now have a single value 'Peter' in the body

To encode a structure back into a JSON string:

-- import "json" package when working with JSON
local json = require("json")
​
-- constructing a new object that we will encode
-- into a JSON string
local new_payload = {
action= "hello",
message= "world"}
​
-- encoding
local encoded_payload, err = json.encode(new_payload)
if err then error(err) end
​
r:SetRequestBody(encoded_payload)
-- webhook request body is now changed to:
-- {
-- "action": "hello",
-- "message: "world"
-- }