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Slack OAuth2

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Slack OAuth2

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Unicode C
#include <C_CkOAuth2W.h>
#include <C_CkJsonObjectW.h>
#include <C_CkFileAccessW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkOAuth2W oauth2;
    const wchar_t *url;
    int numMsWaited;
    HCkJsonObjectW json;
    HCkFileAccessW fac;

    success = FALSE;

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

    oauth2 = CkOAuth2W_Create();

    // 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.
    CkOAuth2W_putAppCallbackUrl(oauth2,L"https://yourwebserver.com/oauth2_redirect");
    CkOAuth2W_putListenPort(oauth2,3017);

    CkOAuth2W_putAuthorizationEndpoint(oauth2,L"https://slack.com/oauth/authorize");
    CkOAuth2W_putTokenEndpoint(oauth2,L"https://slack.com/api/oauth.access");

    // Replace these with actual values.
    CkOAuth2W_putClientId(oauth2,L"CLIENT_ID");
    CkOAuth2W_putClientSecret(oauth2,L"CLIENT_SECRET");

    CkOAuth2W_putScope(oauth2,L"team:read users:read");

    // Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
    url = CkOAuth2W_startAuth(oauth2);
    if (CkOAuth2W_getLastMethodSuccess(oauth2) != TRUE) {
        wprintf(L"%s\n",CkOAuth2W_lastErrorText(oauth2));
        CkOAuth2W_Dispose(oauth2);
        return;
    }

    wprintf(L"url = %s\n",url);

    // Launch the default browser on the system and navigate to the url.
    // The LaunchBrowser method was added in Chilkat v10.1.2.
    success = CkOAuth2W_LaunchBrowser(oauth2,url);
    if (success == FALSE) {
        wprintf(L"%s\n",CkOAuth2W_lastErrorText(oauth2));
        CkOAuth2W_Dispose(oauth2);
        return;
    }

    // Wait for the user to approve or deny authorization in the browser.
    numMsWaited = 0;
    while ((numMsWaited < 90000) && (CkOAuth2W_getAuthFlowState(oauth2) < 3)) {
        CkOAuth2W_SleepMs(oauth2,100);
        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 (CkOAuth2W_getAuthFlowState(oauth2) < 3) {
        CkOAuth2W_Cancel(oauth2);
        wprintf(L"No response from the browser!\n");
        CkOAuth2W_Dispose(oauth2);
        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 (CkOAuth2W_getAuthFlowState(oauth2) == 5) {
        wprintf(L"OAuth2 failed to complete.\n");
        wprintf(L"%s\n",CkOAuth2W_failureInfo(oauth2));
        CkOAuth2W_Dispose(oauth2);
        return;
    }

    if (CkOAuth2W_getAuthFlowState(oauth2) == 4) {
        wprintf(L"OAuth2 authorization was denied.\n");
        wprintf(L"%s\n",CkOAuth2W_accessTokenResponse(oauth2));
        CkOAuth2W_Dispose(oauth2);
        return;
    }

    if (CkOAuth2W_getAuthFlowState(oauth2) != 3) {
        wprintf(L"Unexpected AuthFlowState:%d\n",CkOAuth2W_getAuthFlowState(oauth2));
        CkOAuth2W_Dispose(oauth2);
        return;
    }

    wprintf(L"OAuth2 authorization granted!\n");
    wprintf(L"Access Token = %s\n",CkOAuth2W_accessToken(oauth2));

    // Get the full JSON response:
    json = CkJsonObjectW_Create();
    CkJsonObjectW_Load(json,CkOAuth2W_accessTokenResponse(oauth2));
    CkJsonObjectW_putEmitCompact(json,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"
    // }

    wprintf(L"%s\n",CkJsonObjectW_emit(json));

    // Save the JSON to a file for future requests.
    fac = CkFileAccessW_Create();
    CkFileAccessW_WriteEntireTextFile(fac,L"qa_data/tokens/slack.json",CkJsonObjectW_emit(json),L"utf-8",FALSE);


    CkOAuth2W_Dispose(oauth2);
    CkJsonObjectW_Dispose(json);
    CkFileAccessW_Dispose(fac);

    }