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C

Salesforce OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to get a Salesforce OAuth2 access token from a desktop application or script.

Chilkat C Downloads

C
#include <C_CkOAuth2.h>
#include <C_CkStringBuilder.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkOAuth2 oauth2;
    const char *url;
    int numMsWaited;
    HCkStringBuilder sbJson;

    success = FALSE;

    // To further clarify, see OAuth 2.0 Authorization Flow

    oauth2 = CkOAuth2_Create();

    // This should be the port in the localhost callback URL for your connected app.  
    // The callback URL would look like "http://localhost:3017/" if the port number is 3017.
    CkOAuth2_putListenPort(oauth2,3017);

    CkOAuth2_putAuthorizationEndpoint(oauth2,"https://login.salesforce.com/services/oauth2/authorize");
    CkOAuth2_putTokenEndpoint(oauth2,"https://login.salesforce.com/services/oauth2/token");

    // Replace this with your actual client ID (Consumer Key)
    CkOAuth2_putClientId(oauth2,"CLIENT_ID");

    // We don't have to include the client secret.
    // See the screenshot of our Connected App below..

    // This is for Require Proof Key for Code Exchange (PKCE)
    // See OAuth2 PKCE Explained
    CkOAuth2_putCodeChallenge(oauth2,TRUE);
    CkOAuth2_putCodeChallengeMethod(oauth2,"S256");

    // To force the OAuth consent screen to reappear (even if previously granted), use:
    CkOAuth2_AddAuthQueryParam(oauth2,"prompt","consent");

    // Begin the OAuth2 authorization flow.  This returns a URL that should be loaded in a browser.
    url = CkOAuth2_startAuth(oauth2);
    if (CkOAuth2_getLastMethodSuccess(oauth2) != TRUE) {
        printf("%s\n",CkOAuth2_lastErrorText(oauth2));
        CkOAuth2_Dispose(oauth2);
        return;
    }

    // Launch the default browser on the system and navigate to the url.
    // The LaunchBrowser method was added in Chilkat v10.1.2.
    success = CkOAuth2_LaunchBrowser(oauth2,url);
    if (success == FALSE) {
        printf("%s\n",CkOAuth2_lastErrorText(oauth2));
        CkOAuth2_Dispose(oauth2);
        return;
    }

    // Wait for the user to approve or deny authorization in the browser.
    numMsWaited = 0;
    while ((numMsWaited < 90000) && (CkOAuth2_getAuthFlowState(oauth2) < 3)) {
        CkOAuth2_SleepMs(oauth2,100);
        numMsWaited = numMsWaited + 100;
    }

    // If the browser does not respond within the specified time, AuthFlowState will be:
    // 
    // 1: Waiting for Redirect – The OAuth2 background thread is waiting for the browser's redirect request.
    // 2: Waiting for Final Response – The thread is awaiting the final access token response.
    // In either case, cancel the background task initiated by StartAuth.

    if (CkOAuth2_getAuthFlowState(oauth2) < 3) {
        CkOAuth2_Cancel(oauth2);
        printf("No response from the browser!\n");
        CkOAuth2_Dispose(oauth2);
        return;
    }

    // Check AuthFlowState to determine if authorization was granted, denied, or failed:
    // 
    // 3: Success – OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
    // 4: Access Denied – OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
    // 5: Failure – OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

    if (CkOAuth2_getAuthFlowState(oauth2) == 5) {
        printf("OAuth2 failed to complete.\n");
        printf("%s\n",CkOAuth2_failureInfo(oauth2));
        CkOAuth2_Dispose(oauth2);
        return;
    }

    if (CkOAuth2_getAuthFlowState(oauth2) == 4) {
        printf("OAuth2 authorization was denied.\n");
        printf("%s\n",CkOAuth2_accessTokenResponse(oauth2));
        CkOAuth2_Dispose(oauth2);
        return;
    }

    if (CkOAuth2_getAuthFlowState(oauth2) != 3) {
        printf("Unexpected AuthFlowState:%d\n",CkOAuth2_getAuthFlowState(oauth2));
        CkOAuth2_Dispose(oauth2);
        return;
    }

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

    // Save the full JSON access token response to a file.
    sbJson = CkStringBuilder_Create();
    CkStringBuilder_Append(sbJson,CkOAuth2_accessTokenResponse(oauth2));
    CkStringBuilder_WriteFile(sbJson,"qa_data/tokens/_salesforce.json","utf-8",FALSE);

    // The saved JSON response looks like this:

    // {
    //   "access_token": "00D41000....uLZBpT6",
    //   "refresh_token": "5Aep....25xdGgkrV",
    //   "signature": "cjTbSc5DvcKpaMoRTzuQTJLb1tcMw8LEO01flq4aMD4=",
    //   "scope": "refresh_token id",
    //   "instance_url": "https://d41000000f8a0eak-dev-ed.my.salesforce.com",
    //   "id": "https://login.salesforce.com/id/00D41000000F8A0EAK/005410000....xAAE",
    //   "token_type": "Bearer",
    //   "issued_at": "1738348388166"
    // }

    // --------------------------------------------------------------------------
    // Here's a screenshot of a Salesforce Connected App 
    // with the correct Callback URL for this example,
    // and also selects "Require Proof Key for Code Exchange (PKCE)"
    // and does not requires the secret for the authorization or refresh flow,
    // and also allows for the Client Credentials flow.
    // image


    CkOAuth2_Dispose(oauth2);
    CkStringBuilder_Dispose(sbJson);

    }