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Objective-C

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 Objective-C Downloads

Objective-C
#import <CkoOAuth2.h>
#import <NSString.h>
#import <CkoJsonObject.h>
#import <CkoFileAccess.h>

BOOL success = NO;

// 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.
// -----------------------------------------------------------------------------------------------

CkoOAuth2 *oauth2 = [[CkoOAuth2 alloc] init];

// 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.
oauth2.ListenPort = [NSNumber numberWithInt: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 

oauth2.AuthorizationEndpoint = @"https://login.microsoftonline.com/xxxxxxxxxx-71bf-4ebe-a866-738364321bf2/oauth2/v2.0/authorize";
oauth2.TokenEndpoint = @"https://login.microsoftonline.com/xxxxxxxxxx-71bf-4ebe-a866-738364321bf2/oauth2/v2.0/token";

// Replace these with actual values.
oauth2.ClientId = @"CLIENT_ID";
oauth2.ClientSecret = @"CLIENT_SECRET";

oauth2.CodeChallenge = NO;

// Provide a SPACE separated list of scopes.
// Important: The offline_access scope is needed to get a refresh token.
oauth2.Scope = @"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.
NSString *url = [oauth2 StartAuth];
if (oauth2.LastMethodSuccess == NO) {
    NSLog(@"%@",oauth2.LastErrorText);
    return;
}

// Launch the system's default browser navigated to the URL.
success = [oauth2 LaunchBrowser: url];
if (success == NO) {
    NSLog(@"%@",oauth2.LastErrorText);
    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.
int numMsWaited = 0;
while ((numMsWaited < 90000) && ([oauth2.AuthFlowState intValue] < 3)) {
    [oauth2 SleepMs: [NSNumber numberWithInt: 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 ([oauth2.AuthFlowState intValue] < 3) {
    [oauth2 Cancel];
    NSLog(@"%@",@"No response from the browser!");
    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 ([oauth2.AuthFlowState intValue] == 5) {
    NSLog(@"%@",@"OAuth2 failed to complete.");
    NSLog(@"%@",oauth2.FailureInfo);
    return;
}

if ([oauth2.AuthFlowState intValue] == 4) {
    NSLog(@"%@",@"OAuth2 authorization was denied.");
    NSLog(@"%@",oauth2.AccessTokenResponse);
    return;
}

if ([oauth2.AuthFlowState intValue] != 3) {
    NSLog(@"%@%d",@"Unexpected AuthFlowState:",[oauth2.AuthFlowState intValue]);
    return;
}

NSLog(@"%@",@"OAuth2 authorization granted!");
NSLog(@"%@%@",@"Access Token = ",oauth2.AccessToken);

// Get the full JSON response:
CkoJsonObject *json = [[CkoJsonObject alloc] init];
[json Load: oauth2.AccessTokenResponse];
json.EmitCompact = NO;

// 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"
// }

NSLog(@"%@",[json Emit]);

// Save the JSON to a file for future requests.
CkoFileAccess *fac = [[CkoFileAccess alloc] init];
[fac WriteEntireTextFile: @"qa_data/tokens/office365.json" fileData: [json Emit] charset: @"utf-8" includePreamble: NO];