Java

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. Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean 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}}}'

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

    CkHttpCurl curl = new CkHttpCurl();

    // Provide values for variables.
    curl.SetVar("name","Alice");
    curl.SetVar("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.
    CkStringBuilder sbRawRequest = new CkStringBuilder();
    success = curl.ToRawRequest(sbCurl.getAsString(),sbRawRequest);
    if (success == false) {
        System.out.println(curl.lastErrorText());
        return;
        }

    System.out.println(sbRawRequest.getAsString());

    // 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

    curl.put_EnableBodyVars(false);

    success = curl.ToRawRequest(sbCurl.getAsString(),sbRawRequest);
    if (success == false) {
        System.out.println(curl.lastErrorText());
        return;
        }

    System.out.println(sbRawRequest.getAsString());

    // The raw request with body variable substitution disable:

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