C

Refresh HMRC OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to refresh an HMRC access token. C

#include <C_CkJsonObject.h>
#include <C_CkOAuth2.h>
#include <C_CkDateTime.h>
#include <C_CkStringBuilder.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJsonObject jsonToken;
    HCkOAuth2 oauth2;
    HCkDateTime dtExpire;
    HCkStringBuilder sbJson;

    success = FALSE;

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

    // See Get HMRC Access Token 
    // for sample code showing how to obtain a HMRC access token for desktop apps.

    // It is assumed we previously obtained an OAuth2 access token for HMRC.

    jsonToken = CkJsonObject_Create();
    success = CkJsonObject_LoadFile(jsonToken,"qa_data/tokens/hmrc.json");
    if (success != TRUE) {
        printf("Failed to load hmrc.json\n");
        CkJsonObject_Dispose(jsonToken);
        return;
    }

    // The access token JSON looks something like this:

    // {
    //   "token_type": "Bearer",
    //   "scope": "user_impersonation",
    //   "expires_in": "3599",
    //   "ext_expires_in": "0",
    //   "expires_on": "1524783438",
    //   "not_before": "1524779538",
    //   "resource": "https://mydomain.api.crm.dynamics.com",
    //   "access_token": "...",
    //   "refresh_token": "...",
    //   "id_token": "..."
    // }

    oauth2 = CkOAuth2_Create();

    CkOAuth2_putTokenEndpoint(oauth2,"https://test-api.service.hmrc.gov.uk/oauth/token");

    // Replace these with actual values.
    CkOAuth2_putClientId(oauth2,"HMRC-CLIENT-ID");
    CkOAuth2_putClientSecret(oauth2,"HMRC-CLIENT-SECRET");

    // Get the "refresh_token"
    CkOAuth2_putRefreshToken(oauth2,CkJsonObject_stringOf(jsonToken,"refresh_token"));

    // Send the HTTP POST to refresh the access token..
    success = CkOAuth2_RefreshAccessToken(oauth2);
    if (success != TRUE) {
        printf("%s\n",CkOAuth2_lastErrorText(oauth2));
        CkJsonObject_Dispose(jsonToken);
        CkOAuth2_Dispose(oauth2);
        return;
    }

    // Load the access token response into the json object 
    CkJsonObject_Load(jsonToken,CkOAuth2_accessTokenResponse(oauth2));

    // If an "expires_on" member does not exist, then add the JSON member by
    // getting the current system date/time and adding the "expires_in" seconds.
    // This way we'll know when the token expires.
    if (CkJsonObject_HasMember(jsonToken,"expires_on") == FALSE) {
        dtExpire = CkDateTime_Create();
        CkDateTime_SetFromCurrentSystemTime(dtExpire);
        CkDateTime_AddSeconds(dtExpire,CkJsonObject_IntOf(jsonToken,"expires_in"));
        CkJsonObject_AppendString(jsonToken,"expires_on",CkDateTime_getAsUnixTimeStr(dtExpire,FALSE));
    }

    // Save the new JSON access token response to a file.
    // The access + refresh tokens contained in this JSON will be needed for the next refresh.
    sbJson = CkStringBuilder_Create();
    CkJsonObject_putEmitCompact(jsonToken,FALSE);
    CkJsonObject_EmitSb(jsonToken,sbJson);
    CkStringBuilder_WriteFile(sbJson,"qa_data/tokens/hmrc.json","utf-8",FALSE);

    printf("OAuth2 authorization granted!\n");
    printf("New Access Token = %s\n",CkOAuth2_accessToken(oauth2));


    CkJsonObject_Dispose(jsonToken);
    CkOAuth2_Dispose(oauth2);
    CkDateTime_Dispose(dtExpire);
    CkStringBuilder_Dispose(sbJson);

    }