Delphi DLL Requires Chilkat v11.5.0+

curl with Variable Substitution in the Request Body

See more CURL Examples

This example demonstrates using variables located in the request body with the {{variable_name}} syntax. Delphi DLL

var
success: Boolean;
sbCurl: HCkStringBuilder;
curl: HCkHttpCurl;
sbRawRequest: HCkStringBuilder;

begin
success := False;

//  Variables can also be used within the HTTP request body.
//  Variable names are enclosed between {{ and }}

//  Here is a curl command with two variables {{name}} and {{age}} located in the data.

//  curl -X POST https://api.example.com/data \
//    -H "Content-Type: application/json" \
//    -d '{"name":"{{name}}","age":{{age}}}'

sbCurl := CkStringBuilder_Create();
CkStringBuilder_AppendLn(sbCurl,'curl -X POST https://api.example.com/data \");
CkStringBuilder_AppendLn(sbCurl,'  -H "Content-Type: application/json" \");
CkStringBuilder_AppendLn(sbCurl,'  -d ''{"name":"{{name}}","age":{{age}}}''');

curl := CkHttpCurl_Create();

//  Provide values for variables.
CkHttpCurl_SetVar(curl,'name','Alice');
CkHttpCurl_SetVar(curl,'age','30');

//  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));

//  Output:

//  POST /data HTTP/1.1
//  Host: api.example.com
//  Content-Type: application/json
//  Content-Length: 25
//  
//  {"name":"Alice","age":30}

//  --------------------------------------------------------------------------------------------------
//  Note: Variable substitution in the request body can be turned off by 
//  setting the EnableBodyVars property equal to 0

CkHttpCurl_putEnableBodyVars(curl,False);

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 raw request with body variable substitution disable:

//  Host: api.example.com
//  Content-Type: application/json
//  Content-Length: 33
//  
//  {"name":"{{name}}","age":{{age}}}

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