Objective-C
Dynamics CRM OAuth2 Access Token

Demonstrates how to get a Microsoft Dynamics CRM OAuth2 access token from a desktop (installed) application or script.
Chilkat Objective-C Downloads

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

BOOL success = NO;

//  To further clarify, see OAuth 2.0 Authorization Flow

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

//  This should be the port in the localhost redirect URL for your app.
//  Important: Make sure the redirect URI in your Azure app registration 
//  is exactly "http://localhost:3017/".  Don't forget the ending "/" char.
//  The redirect URL would look like "http://localhost:3017/" if the port number is 3017.
oauth2.ListenPort = [NSNumber numberWithInt:3017];

//  Get the endpoints from the Azure Portal in the "endpoints" section of App Registrations..
//  The DYNAMICS-ENDPOINT-GUID is a Tenant dynamics-endpoint-guid  such as 1b54e7ee-d61b-4f12-a621-a6b2805b98c2
oauth2.AuthorizationEndpoint = @"https://login.microsoftonline.com/DYNAMICS-ENDPOINT-GUID/oauth2/authorize";
oauth2.TokenEndpoint = @"https://login.microsoftonline.com/DYNAMICS-ENDPOINT-GUID/oauth2/token";

//  Replace these with actual values.
oauth2.ClientId = @"DYNAMICS-CRM-CLIENT-ID";
oauth2.ClientSecret = @"DYNAMICS-CRM-SECRET-KEY";

oauth2.Resource = @"https://mydynamicsdomain.api.crm.dynamics.com";

oauth2.RedirectAllowHtml = @"<html><body><p>Thank you for granting access.</p></bod></html>";
oauth2.RedirectDenyHtml = @"<html><body><p>Maybe next time...</p></bod></html>";

//  Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
NSString *url = [oauth2 StartAuth];
if (oauth2.LastMethodSuccess != YES) {
    NSLog(@"%@",oauth2.LastErrorText);
    return;
}

//  We can pre-check the URL by sending a GET to catch any up-front errors.
//  If we receive JSON with an error in response, then we don't proceed any farther.

//  If we receive an HTML response, and the response status = 200, then all should be OK.
//  We can proceed by displaying an interactive browser loaded with the url.
CkoHttp *http = [[CkoHttp alloc] init];
CkoStringBuilder *sbPreCheck = [[CkoStringBuilder alloc] init];
success = [http QuickGetSb: url sbContent: sbPreCheck];
if (([http.LastStatus intValue] != 200) || ([sbPreCheck StartsWith: @"{" caseSensitive: YES] != YES)) {
    NSLog(@"%@",@"JSON Error Response:");
    NSLog(@"%@",[sbPreCheck GetAsString]);
    return;
}

//  If the HTTP request itself failed, then examine the error.
if (success == NO) {
    NSLog(@"%@",http.LastErrorText);
    return;
}

//  OK.. the pre-flight check seems OK, go ahead with getting the interactive user authorization..

//  Launch the default browser on the system and navigate to the url.
//  The LaunchBrowser method was added in Chilkat v10.1.2.
success = [oauth2 LaunchBrowser: url];
if (success == NO) {
    NSLog(@"%@",oauth2.LastErrorText);
    return;
}

//  Wait for the user to approve or deny authorization in the browser.
int numMsWaited = 0;
while ((numMsWaited < 90000) && ([oauth2.AuthFlowState intValue] < 3)) {
    [oauth2 SleepMs: [NSNumber numberWithInt: 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 ([oauth2.AuthFlowState intValue] < 3) {
    [oauth2 Cancel];
    NSLog(@"%@",@"No response from the browser!");
    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 ([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": "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": "..."
//  }

//  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 ([json HasMember: @"expires_on"] != YES) {
    CkoDateTime *dtExpire = [[CkoDateTime alloc] init];
    [dtExpire SetFromCurrentSystemTime];
    [dtExpire AddSeconds: [json IntOf: @"expires_in"]];
    [json AppendString: @"expires_on" value: [dtExpire GetAsUnixTimeStr: NO]];
}

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

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