Making HTTP Requests

Functions can call 3rd party HTTP servers to get additional information for your webhook or just make an API call and end function execution.

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
Batch requests
To send multiple requests asynchronously, create a table containing the requests and call the http.request_batch method:
local http = require("http")
​
-- Prepare a table with requests. Each row in this table contains a table 
-- that needs to have a request method and a URL. You can also add options
-- that add query arguments, authentication, headers, body, etc.
local requests = {
    {"GET", "https://first.example.com", {query="page=1"}},
    {"POST", "https://second.example.com", auth={user="user", pass="pass"}},
    {"PUT", "https://third.example.com", {form="username=john&password=wick"}},
    {"PATCH", "https://fourth.example.com", 
      {
        headers={
	  ["Content-Type"]="application/json"
        },
        body = '{"elon": "musk"}'
      }
    },
}
​
-- Dispatch the requests and wait for all the responses
responses, errors = http.request_batch(requests)
if errors then error(errors) end
​
-- If you need to do something with the responses or 
-- errors, you can view them:
local errorStrings = {}
for _, err in pairs(errors) do
    table.insert(errorStrings, tostring(err))
end
table.sort(errorStrings)
​
-- To access response:
if responses[2]["body"] == "not-expected" then
    -- Do something
end
​
Since all requests are launched asynchronously, 
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.request_batch(requests)
Attributes
Name
Type
Description
requests
Table
A table of requests to send. Each request item is by itself a table containing http.request parameters for the request
Returns
[http.response] or ([http.response], [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 response 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

Name	Type	Description
requests	Table	A table of requests to send. Each request item is by itself a table containing http.request parameters for the request

Testing functions in CLI

Multipart Form Data

Last modified 8mo ago