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Objective-C

Slack OAuth2

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Slack OAuth2

Chilkat Objective-C Downloads

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

BOOL success = NO;

// For more information about the OAuth2, see OAuth 2.0 Authorization Flow

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

// This example is for desktop applicatons (it is not for code that runs on a web server).

// Your applicaton must use your own public web server as an intermediate
// to receive and forward the redirect to localhost.
// See Using Your Web Server as an Intermediary for OAuth2 Redirect to localhost

// This is the Redirect URL defined for your Slack App in the Slack developer portal, and contains the above PHP.
oauth2.AppCallbackUrl = @"https://yourwebserver.com/oauth2_redirect";
oauth2.ListenPort = [NSNumber numberWithInt:3017];

oauth2.AuthorizationEndpoint = @"https://slack.com/oauth/authorize";
oauth2.TokenEndpoint = @"https://slack.com/api/oauth.access";

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

oauth2.Scope = @"team:read users:read";

// 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;
}

NSLog(@"%@%@",@"url = ",url);

// 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:

// {
//   "ok": true,
//   "access_token": "xoxp-348475395242-348621810805-4768936228341-9f512b295124e7c9846ce63cb1464c4d",
//   "scope": "identify,team:read,users:read",
//   "user_id": "UA8HZRUPP",
//   "team_id": "TA3DZBN74",
//   "enterprise_id": null,
//   "team_name": "Chilkat Testing"
// }

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

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