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Java Requires Chilkat v11.5.0+

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.

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Chilkat2 Java
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.HttpCurl;
import com.chilkatsoft.chilkat2.StringBuilder;

public class ChilkatExample {

    public static void main(String[] args) {
        // 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}}}'

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

        HttpCurl curl = new HttpCurl();

        // 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.
        StringBuilder sbRawRequest = new StringBuilder();
        try {
            curl.toRawRequest(sbCurl.getAsString(), sbRawRequest);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            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.setEnableBodyVars(false);

        try {
            curl.toRawRequest(sbCurl.getAsString(), sbRawRequest);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            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}}}
    }
}