(C# UWP/WinRT) Generate an E-way Bill

Demonstrates how to send an HTTP POST request to generate an e-way bill.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

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

//  This example uses the previously obtained access token that was retrieved
//  in this example:  Get EWAY Auth Token using Gstin, username, password, and app_key

Chilkat.JsonObject jsonAuth = new Chilkat.JsonObject();
bool success = jsonAuth.LoadFile("qa_data/tokens/ewayAuth.json");
if (success != true) {
    Debug.WriteLine(jsonAuth.LastErrorText);
    return;
}

//  The jsonAuth contains something like this:
//  {
//    "authToken": "IBTeFtxNfVurg71LTzZ2r0xK7",
//    "decryptedSek": "5g1TyTie7yoslU3DrbYATa7mWyPazlODE7cEh5Vy4Ho="
//  }

//  Generate the JSON data for the e-way bill.
//  The following code can be generated by pasting representative JSON into this online tool:
//  Generate JSON Code
Chilkat.JsonObject jsonData = new Chilkat.JsonObject();
jsonData.UpdateString("supplyType","O");
jsonData.UpdateString("subSupplyType","1");
jsonData.UpdateString("docType","INV");
jsonData.UpdateString("docNo","AW1234-2");
jsonData.UpdateString("docDate","05/04/2018");
jsonData.UpdateString("fromGstin","09ABDC24212B1FK");
jsonData.UpdateString("fromTrdName","willy");
jsonData.UpdateString("fromAddr1","3RD CROSS NO 200  19  A");
jsonData.UpdateString("fromAddr2","GROUND FLOOR OZZY ROAD");
jsonData.UpdateString("fromPlace","BUSY TOWN");
jsonData.UpdateNumber("fromPincode","640033");
jsonData.UpdateNumber("actFromStateCode","05");
jsonData.UpdateNumber("fromStateCode","05");
jsonData.UpdateString("toGstin","01AAAASCC10BBBB");
jsonData.UpdateString("toTrdName","mthustra");
jsonData.UpdateString("toAddr1","Shrek Ogre");
jsonData.UpdateString("toAddr2","Basadronsil");
jsonData.UpdateString("toPlace","Grifl Blagar");
jsonData.UpdateNumber("toPincode","699988");
jsonData.UpdateNumber("actToStateCode","29");
jsonData.UpdateNumber("toStateCode","02");
jsonData.UpdateNumber("totalValue","5609889");
jsonData.UpdateNumber("cgstValue","0");
jsonData.UpdateNumber("sgstValue","0");
jsonData.UpdateNumber("igstValue","168296.67");
jsonData.UpdateNumber("cessValue","224395.56");
jsonData.UpdateString("transporterId","09ABDC24212B1FK");
jsonData.UpdateString("transporterName","");
jsonData.UpdateString("transDocNo","12332");
jsonData.UpdateNumber("transMode","1");
jsonData.UpdateString("transDistance","656");
jsonData.UpdateString("transDocDate","10/04/2018");
jsonData.UpdateString("vehicleNo","PBN4567");
jsonData.UpdateString("vehicleType","R");
jsonData.I = 0;
jsonData.UpdateString("itemList[i].productName","Wheat");
jsonData.UpdateString("itemList[i].productDesc","Wheat");
jsonData.UpdateNumber("itemList[i].hsnCode","1001");
jsonData.UpdateNumber("itemList[i].quantity","4");
jsonData.UpdateString("itemList[i].qtyUnit","BOX");
jsonData.UpdateNumber("itemList[i].cgstRate","0");
jsonData.UpdateNumber("itemList[i].sgstRate","0");
jsonData.UpdateNumber("itemList[i].igstRate","3");
jsonData.UpdateNumber("itemList[i].cessRate","4");
jsonData.UpdateNumber("itemList[i].cessAdvol","0");
jsonData.UpdateNumber("itemList[i].taxableAmount","5609889");

//  The body of the HTTP POST will contain JSON that looks like this:
//  	{
//  	"action":"GENEWAYBILL",
//  	"data": " iJiJGXq ... oUZp/25Y "
//  	}

//  The "data" is the encrypted jsonData using our previously agreed-upon symmetric encryption key.
//  Let's begin build the JSON request body..
Chilkat.JsonObject jsonRequestBody = new Chilkat.JsonObject();
jsonRequestBody.UpdateString("action","GENEWAYBILL");

//  Setup the encryptor using the decryptedSek from the jsonAuth
Chilkat.Crypt2 crypt = new Chilkat.Crypt2();
crypt.CryptAlgorithm = "aes";
crypt.CipherMode = "ecb";
crypt.KeyLength = 256;
crypt.SetEncodedKey(jsonAuth.StringOf("decryptedSek"),"base64");
crypt.EncodingMode = "base64";

//  Encrypt the jsonData and add it to our JSON request body
jsonRequestBody.UpdateString("data",crypt.EncryptStringENC(jsonData.Emit()));

Chilkat.Http http = new Chilkat.Http();

//  Add the authtoken to the request header.
//  Be careful to be precise with uppercase/lowercase ("authtoken" vs "authToken")
http.SetRequestHeader("authtoken",jsonAuth.StringOf("authToken"));
http.SetRequestHeader("Gstin","09ABDC24212B1FK");
http.Accept = "application/json";

//  POST the request to generate an e-way bill:
Chilkat.HttpResponse resp = await http.PostJson2Async("http://ewb.wepgst.com/api/EWayBill","application/json",jsonRequestBody.Emit());
if (http.LastMethodSuccess != true) {
    Debug.WriteLine(http.LastErrorText);
    return;
}

int respStatusCode = resp.StatusCode;
Debug.WriteLine("response status code =" + Convert.ToString(respStatusCode));
Debug.WriteLine("response body:");
Debug.WriteLine(resp.BodyStr);

if (respStatusCode != 200) {

    Debug.WriteLine("Failed in some unknown way.");
    return;
}

//  When the response status code = 200, we'll have either
//  success response like this:
//   {"status":"1","data":"..."}
// 
//  or a failed response like this:
// 
//  {"status":"0","error":"eyJlcnJvckNvZGVzIjoiMTA4In0="}

//  Load the response body into a JSON object.
Chilkat.JsonObject json = new Chilkat.JsonObject();
json.Load(resp.BodyStr);

int status = json.IntOf("status");
Debug.WriteLine("status = " + Convert.ToString(status));

if (status != 1) {
    //  Failed.  Base64 decode the error
    // {"status":"0","error":"eyJlcnJvckNvZGVzIjoiMTA4In0="}
    //  For an invalid password, the error is: {"errorCodes":"108"}
    Chilkat.StringBuilder sbError = new Chilkat.StringBuilder();
    json.StringOfSb("error",sbError);
    sbError.Decode("base64","utf-8");
    Debug.WriteLine("error: " + sbError.GetAsString());
    return;
}

json.EmitCompact = false;
Debug.WriteLine("JSON response:");
Debug.WriteLine(json.Emit());

Chilkat.BinData bdData = new Chilkat.BinData();
bdData.AppendEncoded(json.StringOf("data"),"base64");
crypt.DecryptBd(bdData);

//  Decrypts to
//  {"ewayBillNo":331001121234,"ewayBillDate":"24/05/2018 04:38:00 PM","validUpto":"31/05/2018 11:59:00 PM"}

Chilkat.JsonObject jsonBill = new Chilkat.JsonObject();
jsonBill.Load(bdData.GetString("utf-8"));

int ewayBillNo = jsonBill.IntOf("ewayBillNo");
Debug.WriteLine("ewayBillNo = " + Convert.ToString(ewayBillNo));

string ewayBillDate = jsonBill.StringOf("ewayBillDate");
Debug.WriteLine("ewayBillDate = " + ewayBillDate);

string validUpto = jsonBill.StringOf("validUpto");
Debug.WriteLine("validUpto = " + validUpto);

//  Sample output:

//  ewayBillNo = 331001121234
//  ewayBillDate = 24/05/2018 04:55:00 PM
//  validUpto = 31/05/2018 11:59:00 PM