Lua Requires Chilkat v11.5.0+

curl POST with JSON Input and JSON Output

See more CURL Examples

Demonstrates running a simple curl command with JSON input and JSON output. Lua

local chilkat = require("chilkat")

-- Run the following curl command

--  curl -X POST https://httpbin.org/post \
--       -H "Content-Type: application/json" \
--       -d '{
--             "title": "foo",
--             "body": "bar",
--             "userId": 1
--           }'

-- The backslashes at the end of lines are not required.  Chilkat ignores them if present.
local sbTargetCurl = chilkat.StringBuilder.new()
sbTargetCurl:append_ln(" curl -X POST https://httpbin.org/post \\")
sbTargetCurl:append_ln("      -H \"Content-Type: application/json\" \\")
sbTargetCurl:append_ln("      -d '{")
sbTargetCurl:append_ln("            \"title\": \"foo\",")
sbTargetCurl:append_ln("            \"body\": \"bar\",")
sbTargetCurl:append_ln("            \"userId\": 1")
sbTargetCurl:append_ln("          }'")

local httpCurl = chilkat.HttpCurl.new()

-- Run the curl command.
local success = httpCurl:do_your_thing(sbTargetCurl:get_as_string())
if not success then
    print(httpCurl.last_error_text)
    return
end

local responseJson = chilkat.JsonObject.new()
responseJson.emit_compact = false

httpCurl:get_response_json(responseJson)

local statusCode = httpCurl.status_code
print("response status code: " .. statusCode)

print(responseJson:emit())

-- Output:

-- response status code: 200
-- {
--   "args": {},
--   "data": "{\r\n            \"title\": \"foo\",\r\n            \"body\": \"bar\",\r\n            \"userId\": 1\r\n          }",
--   "files": {},
--   "form": {},
--   "headers": {
--     "Content-Length": "96",
--     "Content-Type": "application/json",
--     "Host": "httpbin.org",
--     "X-Amzn-Trace-Id": "Root=1-69e8db8b-459b3bdf7b7a3bc749184968"
--   },
--   "json": {
--     "body": "bar",
--     "title": "foo",
--     "userId": 1
--   },
--   "origin": "123.222.222.222",
--   "url": "https://httpbin.org/post"
-- }

-- ----------------------------------------------------------------------------------
-- Another example:

-- curl -X POST https://postman-echo.com/post \
--      -H "Content-Type: application/json" \
--      -d '{"foo":"bar"}'

local targetCurl = "curl -X POST https://postman-echo.com/post -H \"Content-Type: application/json\" -d '{\"foo\":\"bar\"}'"

-- Run the curl command.
success = httpCurl:do_your_thing(targetCurl)
if not success then
    print(httpCurl.last_error_text)
    return
end

httpCurl:get_response_json(responseJson)

statusCode = httpCurl.status_code
print("response status code: " .. statusCode)

print(responseJson:emit())

-- Output:

-- response status code: 200
-- {
--   "args": {},
--   "data": {
--     "foo": "bar"
--   },
--   "files": {},
--   "form": {},
--   "headers": {
--     "host": "postman-echo.com",
--     "content-length": "13",
--     "content-type": "application/json",
--     "x-forwarded-proto": "https",
--     "accept-encoding": "gzip, br"
--   },
--   "json": {
--     "foo": "bar"
--   },
--   "url": "https://postman-echo.com/post"
-- }