Unicode C

curl with Variable Substitution in the Request Body

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

#include <C_CkStringBuilderW.h>
#include <C_CkHttpCurlW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkStringBuilderW sbCurl;
    HCkHttpCurlW curl;
    HCkStringBuilderW sbRawRequest;

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

    curl = CkHttpCurlW_Create();

    // Provide values for variables.
    CkHttpCurlW_SetVar(curl,L"name",L"Alice");
    CkHttpCurlW_SetVar(curl,L"age",L"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 = CkStringBuilderW_Create();
    success = CkHttpCurlW_ToRawRequest(curl,CkStringBuilderW_getAsString(sbCurl),sbRawRequest);
    if (success == FALSE) {
        wprintf(L"%s\n",CkHttpCurlW_lastErrorText(curl));
        CkStringBuilderW_Dispose(sbCurl);
        CkHttpCurlW_Dispose(curl);
        CkStringBuilderW_Dispose(sbRawRequest);
        return;
    }

    wprintf(L"%s\n",CkStringBuilderW_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 FALSE

    CkHttpCurlW_putEnableBodyVars(curl,FALSE);

    success = CkHttpCurlW_ToRawRequest(curl,CkStringBuilderW_getAsString(sbCurl),sbRawRequest);
    if (success == FALSE) {
        wprintf(L"%s\n",CkHttpCurlW_lastErrorText(curl));
        CkStringBuilderW_Dispose(sbCurl);
        CkHttpCurlW_Dispose(curl);
        CkStringBuilderW_Dispose(sbRawRequest);
        return;
    }

    wprintf(L"%s\n",CkStringBuilderW_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}}}


    CkStringBuilderW_Dispose(sbCurl);
    CkHttpCurlW_Dispose(curl);
    CkStringBuilderW_Dispose(sbRawRequest);

    }