Lua Requires Chilkat v11.5.0+

curl with Variable Substitution in an XML Request Body

See more CURL Examples

This example shows how to use variables inside an XML request body using the {{variable_name}} syntax. When the HTTP request’s Content-Type indicates XML, Chilkat automatically applies proper XML entity encoding to each substituted value, ensuring the resulting XML remains valid. Lua

local chilkat = require("chilkat")

-- Variable names are enclosed between {{ and }}

-- curl -X POST https://api.example.com/api/orders \
--   -H "Content-Type: application/xml; charset=utf-8" \
--   -H "Accept: application/xml" \
--   -d '<order>
--   <customerName>{{customer_name}}</customerName>
--   <note>{{note}}</note>
--   <address>{{address}}</address>
--   <instructions>{{instructions}}</instructions>
-- </order>'

local sbCurl = chilkat.StringBuilder.new()
sbCurl:append_ln("curl -X POST https://api.example.com/api/orders \\")
sbCurl:append_ln("  -H \"Content-Type: application/xml; charset=utf-8\" \\")
sbCurl:append_ln("  -H \"Accept: application/xml\" \\")
sbCurl:append_ln("  -d '<order>")
sbCurl:append_ln("  <customerName>{{customer_name}}</customerName>")
sbCurl:append_ln("  <note>{{note}}</note>")
sbCurl:append_ln("  <address>{{address}}</address>")
sbCurl:append_ln("  <instructions>{{instructions}}</instructions>")
sbCurl:append_ln("</order>'")

local curl = chilkat.HttpCurl.new()

-- The values below contain chars that will require XML entity encoding.
-- Chilkat will automatically do the encoding because the Content-Type of this request is "application/xml"
curl:set_var("customer_name", "John & Sons")
curl:set_var("note", "He said \"Ship it ASAP!\"")
curl:set_var("address", "123 <Main> Street")
curl:set_var("instructions", "Use door #2 & call upon arrival")

-- To demonstrate how the variables are replaced, this example does not execute the curl command.
-- Instead, it generates the raw HTTP request that would be sent if the curl command were run.
local sbRawRequest = chilkat.StringBuilder.new()
local success = curl:to_raw_request(sbCurl:get_as_string(), sbRawRequest)
if not success then
    print(curl.last_error_text)
    return
end

print(sbRawRequest:get_as_string())

-- The output is shown below.
-- Notice the chars that were XML entity encoded.

-- POST /api/orders HTTP/1.1
-- Accept: application/xml
-- Host: api.example.com
-- Content-Type: application/xml; charset=utf-8
-- Content-Length: 229
--
-- <order>
--   <customerName>John &amp; Sons</customerName>
--   <note>He said &quot;Ship it ASAP!&quot;</note>
--   <address>123 &lt;Main&gt; Street</address>
--   <instructions>Use door #2 &amp; call upon arrival</instructions>
-- </order>