Delphi DLL

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. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, HttpCurl, StringBuilder;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
sbCurl: HCkStringBuilder;
curl: HCkHttpCurl;
sbRawRequest: HCkStringBuilder;

begin
success := False;

// 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>'

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

curl := CkHttpCurl_Create();

// 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"
CkHttpCurl_SetVar(curl,'customer_name','John & Sons');
CkHttpCurl_SetVar(curl,'note','He said "Ship it ASAP!"');
CkHttpCurl_SetVar(curl,'address','123 <Main> Street');
CkHttpCurl_SetVar(curl,'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.
sbRawRequest := CkStringBuilder_Create();
success := CkHttpCurl_ToRawRequest(curl,CkStringBuilder__getAsString(sbCurl),sbRawRequest);
if (success = False) then
  begin
    Memo1.Lines.Add(CkHttpCurl__lastErrorText(curl));
    Exit;
  end;

Memo1.Lines.Add(CkStringBuilder__getAsString(sbRawRequest));

// 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>

CkStringBuilder_Dispose(sbCurl);
CkHttpCurl_Dispose(curl);
CkStringBuilder_Dispose(sbRawRequest);

end;