(Java) Debug REST HTTP Request

Demonstrates how to generate the HTTP Request (with all headers intact) without actually sending the request.

Note: This example requires Chilkat v9.5.0.77 or later.

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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[])
  {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // This example will connect to the web server, but does not actually send a request.
    // When in DebugMode, the request is composed in memory and can be retrieved by calling
    // GetLastDebugRequest.

    CkRest rest = new CkRest();

    // Connect Code...
    // URL: https://test-api.service.hmrc.gov.uk/organisations/vat/MY_HMRC_VRN/returns
    boolean bTls = true;
    int port = 443;
    boolean bAutoReconnect = true;
    boolean success = rest.Connect("test-api.service.hmrc.gov.uk",port,bTls,bAutoReconnect);
    if (success != true) {
        System.out.println("ConnectFailReason: " + rest.get_ConnectFailReason());
        System.out.println(rest.lastErrorText());
        return;
        }

    // Build the request body...
    CkJsonObject json = new CkJsonObject();
    json.UpdateString("periodKey","A001");
    json.UpdateNumber("vatDueSales","105.50");
    json.UpdateNumber("vatDueAcquisitions","-100.45");
    json.UpdateNumber("totalVatDue","5.05");
    json.UpdateNumber("vatReclaimedCurrPeriod","105.15");
    json.UpdateNumber("netVatDue","100.10");
    json.UpdateInt("totalValueSalesExVAT",300);
    json.UpdateInt("totalValuePurchasesExVAT",300);
    json.UpdateInt("totalValueGoodsSuppliedExVAT",3000);
    json.UpdateInt("totalAcquisitionsExVAT",3000);
    json.UpdateBool("finalised",true);

    // Add Headers...
    rest.AddHeader("Accept","application/vnd.hmrc.1.0+json");
    rest.AddHeader("Authorization","Bearer HMRC_ACCESS_TOKEN");
    rest.AddHeader("Content-Type","application/json");

    CkStringBuilder sbRequestBody = new CkStringBuilder();
    json.EmitSb(sbRequestBody);

    // Set DebugMode so that no request is actually sent.
    rest.put_DebugMode(true);

    CkStringBuilder sbResponseBody = new CkStringBuilder();
    success = rest.FullRequestSb("POST","/organisations/vat/MY_HMRC_VRN/returns",sbRequestBody,sbResponseBody);
    if (success != true) {
        System.out.println(rest.lastErrorText());
        return;
        }

    // Get the exact contents of what would've been sent.
    // This includes the HTTP start line, the HTTP request headers, and the request body.
    // Given that it's possible for the request body to contain binary data,
    // the GetLastDebugRequest fetches into a BinData object.
    // In this case, however, our request body contained JSON, so we can
    // examine it as a string..
    CkBinData bdRequest = new CkBinData();
    success = rest.GetLastDebugRequest(bdRequest);

    System.out.println("----");
    System.out.println(bdRequest.getString("utf-8"));
    System.out.println("----");

    // The output for the above case:

    // POST /organisations/vat/MY_HMRC_VRN/returns HTTP/1.1
    // Accept: application/vnd.hmrc.1.0+json
    // Host: test-api.service.hmrc.gov.uk
    // Authorization: Bearer HMRC_ACCESS_TOKEN
    // Content-Type: application/json
    // Content-Length: 281
    // 
    // {"periodKey":"A001","vatDueSales":105.50, ... ,"finalised":true}
    // 
    // 
  }
}