Making HTTP requests

Functions can make multiple HTTP request calls to any external server. Some of the uses cases:

  • Call 3rd party API to get additional authentication tokens before forwarding request.
  • Send data to the external service directly, without relying on the webhook.
  • Get additional data to the function so it can dynamically mutate the payload.

Using HTTP package

To make an HTTP request from Lua function, import ‘http’ package:

-- importing HTTP package
local http = require("http")

-- making HTTP call
response, err = http.request("GET", "https://example.com")
if err then error(err) end

-- parsing response body from the API
local api_response, err = json.decode(response.body)
if err then error(err) end

Specify request body

You can also make a POST, PUT, DELETE requests to a 3rd party APIs:

-- importing HTTP and JSON packages
local json = require("json")
local http = require("http")

local payload, err = json.encode({
    action = "create_record",
    user = "example",
})
if err then error(err) end

local resp, err = http.request("POST", "http://example.com/api", { body = payload})
if err then error(err) end

Reading response body

To read response body:

-- importing HTTP package
local http = require("http")

-- making HTTP call
response, err = http.request("GET", "https://example.com")
if err then error(err) end

-- received JSON string:
-- {
--   "firstname": "luke",
--   "lastname": "skywalker"  
-- }

-- parsing response body from the API
local api_response, err = json.decode(response.body)
if err then error(err) end

-- access values like 'api_response.firstname'

Query, headers, timeout

To specify query, timeout and headers:

-- importing HTTP package
local http = require("http")

-- specifying headers
local headers = {}
headers["Authorization"] = "Basic " .. "123456"

-- making HTTP call
response, err = http.request("GET", "https://example.com", {
    query="page=1",
    timeout="5s",
    headers={
        Accept="*/*"
    }
})
if err then error(err) end

-- parsing response body from the API
local api_response, err = json.decode(response.body)
if err then error(err) end

HTTP package API reference

http.delete(url [, options])

Attributes

Name Type Description
url String URL of the resource to load
options Table Additional options

Options

Name Type Description
query String URL encoded query params
cookies Table Additional cookies to send with the request
headers Table Additional headers to send with the request

Returns

http.response or (nil, error message)

http.get(url [, options])

Attributes

Name Type Description
url String URL of the resource to load
options Table Additional options

Options

Name Type Description
query String URL encoded query params
cookies Table Additional cookies to send with the request
headers Table Additional headers to send with the request

Returns

http.response or (nil, error message)

http.head(url [, options])

Attributes

Name Type Description
url String URL of the resource to load
options Table Additional options

Options

Name Type Description
query String URL encoded query params
cookies Table Additional cookies to send with the request
headers Table Additional headers to send with the request

Returns

http.response or (nil, error message)

http.patch(url [, options])

Attributes

Name Type Description
url String URL of the resource to load
options Table Additional options

Options

Name Type Description
query String URL encoded query params
cookies Table Additional cookies to send with the request
body String Request body.
form String Deprecated. URL encoded request body. This will also set the Content-Type header to application/x-www-form-urlencoded
headers Table Additional headers to send with the request

Returns

http.response or (nil, error message)

http.post(url [, options])

Attributes

Name Type Description
url String URL of the resource to load
options Table Additional options

Options

Name Type Description
query String URL encoded query params
cookies Table Additional cookies to send with the request
body String Request body.
form String Deprecated. URL encoded request body. This will also set the Content-Type header to application/x-www-form-urlencoded
headers Table Additional headers to send with the request

Returns

http.response or (nil, error message)

http.put(url [, options])

Attributes

Name Type Description
url String URL of the resource to load
options Table Additional options

Options

Name Type Description
query String URL encoded query params
cookies Table Additional cookies to send with the request
body String Request body.
form String Deprecated. URL encoded request body. This will also set the Content-Type header to application/x-www-form-urlencoded
headers Table Additional headers to send with the request

Returns

http.response or (nil, error message)

http.request(method, url [, options])

Attributes

Name Type Description
method String The HTTP request method
url String URL of the resource to load
options Table Additional options

Options

Name Type Description
query String URL encoded query params
cookies Table Additional cookies to send with the request
body String Request body.
form String Deprecated. URL encoded request body. This will also set the Content-Type header to application/x-www-form-urlencoded
headers Table Additional headers to send with the request

Returns

http.response or (nil, error message)

http.response

The http.response table contains information about a completed HTTP request.

Attributes

Name Type Description
body String The HTTP response body
body_size Number The size of the HTTP reponse body in bytes
headers Table The HTTP response headers
cookies Table The cookies sent by the server in the HTTP response
status_code Number The HTTP response status code
url String The final URL the request ended pointing to after redirects