Unicode C
Unicode C
Get E-way Bill System Access Token
See more HTTP Misc Examples
Sends a request to get an E-way bill system access token.Chilkat Unicode C Downloads
#include <C_CkPublicKeyW.h>
#include <C_CkRsaW.h>
#include <C_CkPrngW.h>
#include <C_CkJsonObjectW.h>
#include <C_CkHttpW.h>
#include <C_CkHttpResponseW.h>
#include <C_CkStringBuilderW.h>
#include <C_CkCrypt2W.h>
#include <C_CkBinDataW.h>
#include <C_CkFileAccessW.h>
void ChilkatSample(void)
{
BOOL success;
HCkPublicKeyW pubkey;
const wchar_t *password;
HCkRsaW rsa;
const wchar_t *encPassword;
HCkPrngW prng;
const wchar_t *app_key;
const wchar_t *encAppKey;
HCkJsonObjectW jsonBody;
HCkHttpW http;
HCkHttpResponseW resp;
int respStatusCode;
HCkJsonObjectW json;
int status;
HCkStringBuilderW sbError;
const wchar_t *authToken;
HCkCrypt2W crypt;
HCkBinDataW bdSek;
HCkJsonObjectW jsonEwayAuth;
HCkFileAccessW fac;
success = FALSE;
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
// First load the public key provided by the E-way bill System
pubkey = CkPublicKeyW_Create();
success = CkPublicKeyW_LoadFromFile(pubkey,L"qa_data/pem/eway_publickey.pem");
if (success == FALSE) {
wprintf(L"%s\n",CkPublicKeyW_lastErrorText(pubkey));
CkPublicKeyW_Dispose(pubkey);
return;
}
// Encrypt the password using the RSA public key provided by eway..
password = L"my_wepgst_password";
rsa = CkRsaW_Create();
CkRsaW_putCharset(rsa,L"utf-8");
CkRsaW_putEncodingMode(rsa,L"base64");
success = CkRsaW_UsePublicKey(rsa,pubkey);
if (success == FALSE) {
wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
CkPublicKeyW_Dispose(pubkey);
CkRsaW_Dispose(rsa);
return;
}
// Returns the encrypted password as base64 (because the EncodingMode = "base64")
encPassword = CkRsaW_encryptStringENC(rsa,password,FALSE);
if (CkRsaW_getLastMethodSuccess(rsa) == FALSE) {
wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
CkPublicKeyW_Dispose(pubkey);
CkRsaW_Dispose(rsa);
return;
}
// Generate a random app_key. This should be 32 bytes (us-ascii chars)
// We need 32 bytes because we'll be doing 256-bit AES ECB encryption, and 32 bytes = 256 bits.
prng = CkPrngW_Create();
// Generate a random string containing some numbers, uppercase, and lowercase.
app_key = CkPrngW_randomString(prng,32,TRUE,TRUE,TRUE);
wprintf(L"app_key = %s\n",app_key);
// RSA encrypt the app_key.
encAppKey = CkRsaW_encryptStringENC(rsa,app_key,FALSE);
if (CkRsaW_getLastMethodSuccess(rsa) == FALSE) {
wprintf(L"%s\n",CkRsaW_lastErrorText(rsa));
CkPublicKeyW_Dispose(pubkey);
CkRsaW_Dispose(rsa);
CkPrngW_Dispose(prng);
return;
}
// Prepare the JSON body for the HTTP POST that gets the access token.
jsonBody = CkJsonObjectW_Create();
CkJsonObjectW_UpdateString(jsonBody,L"action",L"ACCESSTOKEN");
// Use your username instead of "09ABDC24212B1FK".
CkJsonObjectW_UpdateString(jsonBody,L"username",L"09ABDC24212B1FK");
CkJsonObjectW_UpdateString(jsonBody,L"password",encPassword);
CkJsonObjectW_UpdateString(jsonBody,L"app_key",encAppKey);
http = CkHttpW_Create();
// Add required headers.
// Use your ewb-user-id instead of "03AEXPR16A9M010"
CkHttpW_SetRequestHeader(http,L"ewb-user-id",L"03AEXPR16A9M010");
// The Gstin should be the same as the username in the jsonBody above.
CkHttpW_SetRequestHeader(http,L"Gstin",L"09ABDC24212B1FK");
CkHttpW_putAccept(http,L"application/json");
// POST the JSON...
resp = CkHttpResponseW_Create();
success = CkHttpW_HttpJson(http,L"POST",L"http://ewb.wepgst.com/api/Authenticate",jsonBody,L"application/json",resp);
if (success == FALSE) {
wprintf(L"%s\n",CkHttpW_lastErrorText(http));
CkPublicKeyW_Dispose(pubkey);
CkRsaW_Dispose(rsa);
CkPrngW_Dispose(prng);
CkJsonObjectW_Dispose(jsonBody);
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
return;
}
respStatusCode = CkHttpResponseW_getStatusCode(resp);
wprintf(L"response status code =%d\n",respStatusCode);
wprintf(L"response body:\n");
wprintf(L"%s\n",CkHttpResponseW_bodyStr(resp));
if (respStatusCode != 200) {
wprintf(L"Failed in some unknown way.\n");
CkPublicKeyW_Dispose(pubkey);
CkRsaW_Dispose(rsa);
CkPrngW_Dispose(prng);
CkJsonObjectW_Dispose(jsonBody);
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
return;
}
// When the response status code = 200, we'll have either
// success response like this:
// {"status":"1","authtoken":"...","sek":"..."}
//
// or a failed response like this:
//
// {"status":"0","error":"eyJlcnJvckNvZGVzIjoiMTA4In0="}
// Load the response body into a JSON object.
json = CkJsonObjectW_Create();
CkJsonObjectW_Load(json,CkHttpResponseW_bodyStr(resp));
status = CkJsonObjectW_IntOf(json,L"status");
wprintf(L"status = %d\n",status);
if (status != 1) {
// Failed. Base64 decode the error
// {"status":"0","error":"eyJlcnJvckNvZGVzIjoiMTA4In0="}
// For an invalid password, the error is: {"errorCodes":"108"}
sbError = CkStringBuilderW_Create();
CkJsonObjectW_StringOfSb(json,L"error",sbError);
CkStringBuilderW_Decode(sbError,L"base64",L"utf-8");
wprintf(L"error: %s\n",CkStringBuilderW_getAsString(sbError));
CkPublicKeyW_Dispose(pubkey);
CkRsaW_Dispose(rsa);
CkPrngW_Dispose(prng);
CkJsonObjectW_Dispose(jsonBody);
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
CkJsonObjectW_Dispose(json);
CkStringBuilderW_Dispose(sbError);
return;
}
// At this point, we know the request was entirely successful.
authToken = CkJsonObjectW_stringOf(json,L"authtoken");
// Decrypt the sek key using our app_key.
crypt = CkCrypt2W_Create();
CkCrypt2W_putCryptAlgorithm(crypt,L"aes");
CkCrypt2W_putCipherMode(crypt,L"ecb");
CkCrypt2W_putKeyLength(crypt,256);
CkCrypt2W_SetEncodedKey(crypt,app_key,L"us-ascii");
CkCrypt2W_putEncodingMode(crypt,L"base64");
bdSek = CkBinDataW_Create();
CkBinDataW_AppendEncoded(bdSek,CkJsonObjectW_stringOf(json,L"sek"),L"base64");
CkCrypt2W_DecryptBd(crypt,bdSek);
// bdSek now contains the decrypted symmetric encryption key...
// We'll use it to encrypt the JSON payloads we send.
// Let's persist our authtoken and decrypted sek (symmetric encryption key).
// To send EWAY requests (such as to create an e-way bill), we'll just load
// and use these pre-obtained credentials.
jsonEwayAuth = CkJsonObjectW_Create();
CkJsonObjectW_UpdateString(jsonEwayAuth,L"authToken",authToken);
CkJsonObjectW_UpdateString(jsonEwayAuth,L"decryptedSek",CkBinDataW_getEncoded(bdSek,L"base64"));
CkJsonObjectW_putEmitCompact(jsonEwayAuth,FALSE);
fac = CkFileAccessW_Create();
CkFileAccessW_WriteEntireTextFile(fac,L"qa_data/tokens/ewayAuth.json",CkJsonObjectW_emit(jsonEwayAuth),L"utf-8",FALSE);
wprintf(L"Saved:\n");
wprintf(L"%s\n",CkJsonObjectW_emit(jsonEwayAuth));
// Sample output:
// {
// "authToken": "IBTeFtxNfVurg71LTzZ2r0xK7",
// "decryptedSek": "5g1TyTie7yoslU3DrbYATa7mWyPazlODE7cEh5Vy4Ho="
//
CkPublicKeyW_Dispose(pubkey);
CkRsaW_Dispose(rsa);
CkPrngW_Dispose(prng);
CkJsonObjectW_Dispose(jsonBody);
CkHttpW_Dispose(http);
CkHttpResponseW_Dispose(resp);
CkJsonObjectW_Dispose(json);
CkStringBuilderW_Dispose(sbError);
CkCrypt2W_Dispose(crypt);
CkBinDataW_Dispose(bdSek);
CkJsonObjectW_Dispose(jsonEwayAuth);
CkFileAccessW_Dispose(fac);
}