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C#

Slack OAuth2

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Slack OAuth2

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C#
bool success = false;

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

Chilkat.OAuth2 oauth2 = new Chilkat.OAuth2();

//  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 = 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.
string url = oauth2.StartAuth();
if (oauth2.LastMethodSuccess != true) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

Debug.WriteLine("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 == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

//  Wait for the user to approve or deny authorization in the browser.
int numMsWaited = 0;
while ((numMsWaited < 90000) && (oauth2.AuthFlowState < 3)) {
    oauth2.SleepMs(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 < 3) {
    oauth2.Cancel();
    Debug.WriteLine("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 == 5) {
    Debug.WriteLine("OAuth2 failed to complete.");
    Debug.WriteLine(oauth2.FailureInfo);
    return;
}

if (oauth2.AuthFlowState == 4) {
    Debug.WriteLine("OAuth2 authorization was denied.");
    Debug.WriteLine(oauth2.AccessTokenResponse);
    return;
}

if (oauth2.AuthFlowState != 3) {
    Debug.WriteLine("Unexpected AuthFlowState:" + Convert.ToString(oauth2.AuthFlowState));
    return;
}

Debug.WriteLine("OAuth2 authorization granted!");
Debug.WriteLine("Access Token = " + oauth2.AccessToken);

//  Get the full JSON response:
Chilkat.JsonObject json = new Chilkat.JsonObject();
json.Load(oauth2.AccessTokenResponse);
json.EmitCompact = false;

//  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"
//  }

Debug.WriteLine(json.Emit());

//  Save the JSON to a file for future requests.
Chilkat.FileAccess fac = new Chilkat.FileAccess();
fac.WriteEntireTextFile("qa_data/tokens/slack.json",json.Emit(),"utf-8",false);