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Office365 OAuth2 Access Token for SMTP, IMAP, POP

See more Office365 Examples

Demonstrates how to get an OAuth2 access token for use in the SMTP, IMAP, and POP3 protocols.

Note: It is only the initial access token that must be obtained interactively using a browser (see the code and comments below). Once the initial OAuth2 access token is obtained, then it can refreshed indefinitely with no user interaction.

Chilkat C Downloads

C
#include <C_CkOAuth2.h>
#include <C_CkJsonObject.h>
#include <C_CkFileAccess.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkOAuth2 oauth2;
    const char *url;
    int numMsWaited;
    HCkJsonObject json;
    HCkFileAccess fac;

    success = FALSE;

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

    // -----------------------------------------------------------------------------------------------
    // Important:  Setup your App Registration in Azure beforehand.  
    // 
    // See Create Azure App Registration for use with IMAP, POP3, and SMTP
    // 
    // Also, a detail that is often missed.  Make sure to specify "Web" for your Redirect URI.
    // See Solution for Azure OAuth2 Error: Public clients can't send a client secret.
    // -----------------------------------------------------------------------------------------------

    oauth2 = CkOAuth2_Create();

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

    // Specify your OAuth2 authorization and token endpoints
    // Replace "xxxxxxxxxx-71bf-4ebe-a866-738364321bf2" with your tenant ID, 
    // or one of the following keywords: "common", "organizations", "consumers".
    // 
    // For more information about the /authorize endpoint, see Microsoft identity platform and OAuth 2.0 authorization code flow 

    CkOAuth2_putAuthorizationEndpoint(oauth2,"https://login.microsoftonline.com/xxxxxxxxxx-71bf-4ebe-a866-738364321bf2/oauth2/v2.0/authorize");
    CkOAuth2_putTokenEndpoint(oauth2,"https://login.microsoftonline.com/xxxxxxxxxx-71bf-4ebe-a866-738364321bf2/oauth2/v2.0/token");

    // Replace these with actual values.
    CkOAuth2_putClientId(oauth2,"CLIENT_ID");
    CkOAuth2_putClientSecret(oauth2,"CLIENT_SECRET");

    CkOAuth2_putCodeChallenge(oauth2,FALSE);

    // Provide a SPACE separated list of scopes.
    // Important: The offline_access scope is needed to get a refresh token.
    CkOAuth2_putScope(oauth2,"openid profile offline_access https://outlook.office365.com/SMTP.Send https://outlook.office365.com/POP.AccessAsUser.All https://outlook.office365.com/IMAP.AccessAsUser.All");

    // ----------------------------------------------------------------------
    // Note: It is only the initial access token that must be obtained interactively using a browser.  
    // Once the initial OAuth2 access token is obtained, then it can refreshed indefinitely with no user interaction.
    // ----------------------------------------------------------------------

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

    // Launch the system's default browser navigated to the URL.
    success = CkOAuth2_LaunchBrowser(oauth2,url);
    if (success == FALSE) {
        printf("%s\n",CkOAuth2_lastErrorText(oauth2));
        CkOAuth2_Dispose(oauth2);
        return;
    }

    // ----------------------------------------------------------------------
    // Note: Read about how browser caching of credentials can cause problems.
    // See OAuth2 Browser Caching Credentials
    // ----------------------------------------------------------------------

    // Now wait for the authorization.
    // We'll wait for a max of 90 seconds.
    numMsWaited = 0;
    while ((numMsWaited < 90000) && (CkOAuth2_getAuthFlowState(oauth2) < 3)) {
        CkOAuth2_SleepMs(oauth2,100);
        numMsWaited = numMsWaited + 100;
    }

    // If there was no response from the browser within 30 seconds, then 
    // the AuthFlowState will be equal to 1 or 2.
    // 1: Waiting for Redirect. The OAuth2 background thread is waiting to receive the redirect HTTP request from the browser.
    // 2: Waiting for Final Response. The OAuth2 background thread is waiting for the final access token response.
    // In that case, cancel the background task started in the call to StartAuth.
    if (CkOAuth2_getAuthFlowState(oauth2) < 3) {
        CkOAuth2_Cancel(oauth2);
        printf("No response from the browser!\n");
        CkOAuth2_Dispose(oauth2);
        return;
    }

    // Check the AuthFlowState to see if authorization was granted, denied, or if some error occurred
    // The possible AuthFlowState values are:
    // 3: Completed with Success. The OAuth2 flow has completed, the background thread exited, and the successful JSON response is available in AccessTokenResponse property.
    // 4: Completed with Access Denied. The OAuth2 flow has completed, the background thread exited, and the error JSON is available in AccessTokenResponse property.
    // 5: Failed Prior to Completion. The OAuth2 flow failed to complete, the background thread exited, and the error information is available in the FailureInfo property.
    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));

    // Get the full JSON response:
    json = CkJsonObject_Create();
    CkJsonObject_Load(json,CkOAuth2_accessTokenResponse(oauth2));
    CkJsonObject_putEmitCompact(json,FALSE);

    // The JSON response looks like this:
    // 
    // {
    //   "token_type": "Bearer",
    //   "scope": "IMAP.AccessAsUser.All openid POP.AccessAsUser.All profile SMTP.Send email",
    //   "expires_in": 3599,
    //   "ext_expires_in": 3599,
    //   "access_token": "...",
    //   "refresh_token": "...",
    //   "id_token": "...",
    //   "expires_on": "1592748507"
    // }

    printf("%s\n",CkJsonObject_emit(json));

    // Save the JSON to a file for future requests.
    fac = CkFileAccess_Create();
    CkFileAccess_WriteEntireTextFile(fac,"qa_data/tokens/office365.json",CkJsonObject_emit(json),"utf-8",FALSE);


    CkOAuth2_Dispose(oauth2);
    CkJsonObject_Dispose(json);
    CkFileAccess_Dispose(fac);

    }