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Node.js

Get a Google Calendar OAuth2 Access Token

See more Google Calendar Examples

Demonstrates how to get a Google Calendar OAuth2 access token from a desktop application or script.

Chilkat Node.js Downloads

Node.js
NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    var oauth2 = new chilkat.OAuth2();

    // For Google OAuth2, set the listen port equal to the port used
    // in the Authorized Redirect URL for the Client ID.
    // For example, in this case the Authorized Redirect URL would be http://localhost:55568/
    // Your app should choose a port not likely not used by any other application.
    oauth2.ListenPort = 55568;

    oauth2.AuthorizationEndpoint = "https://accounts.google.com/o/oauth2/v2/auth";
    oauth2.TokenEndpoint = "https://www.googleapis.com/oauth2/v4/token";

    // Replace these with actual values.
    oauth2.ClientId = "GOOGLE-CLIENT-ID";
    oauth2.ClientSecret = "GOOGLE-CLIENT-SECRET";

    oauth2.CodeChallenge = true;
    oauth2.CodeChallengeMethod = "S256";

    // These are the scopes for Google Calendar:
    // https://www.googleapis.com/auth/calendar 	read/write access to Calendars
    // https://www.googleapis.com/auth/calendar.readonly 	read-only access to Calendars
    oauth2.Scope = "https://www.googleapis.com/auth/calendar";

    // Begin the OAuth2 three-legged flow.  This returns a URL that should be loaded in a browser.
    var url = oauth2.StartAuth();
    if (oauth2.LastMethodSuccess == false) {
        console.log(oauth2.LastErrorText);
        return;
    }

    console.log(url);

    // Launch the system's default browser navigated to the URL.
    success = oauth2.LaunchBrowser(url);
    if (success == false) {
        console.log(oauth2.LastErrorText);
        return;
    }

    // Now wait for the authorization.
    // We'll wait for a max of 30 seconds.
    var numMsWaited = 0;
    while ((numMsWaited < 30000) && (oauth2.AuthFlowState < 3)) {
        oauth2.SleepMs(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 < 3) {
        oauth2.Cancel();
        console.log("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 == 5) {
        console.log("OAuth2 failed to complete.");
        console.log(oauth2.FailureInfo);
        return;
    }

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

    if (oauth2.AuthFlowState !== 3) {
        console.log("Unexpected AuthFlowState:" + oauth2.AuthFlowState);
        return;
    }

    // Save the full JSON access token response to a file.
    var sbJson = new chilkat.StringBuilder();
    sbJson.Append(oauth2.AccessTokenResponse);
    sbJson.WriteFile("qa_data/tokens/googleCalendar.json","utf-8",false);

    // The saved JSON response looks like this:

    // 	{
    // 	 "access_token": "ya39.Ci-XA_C5bGgRDC3UaD-h0_NeL-DVIQnI2gHtBBBHkZzrwlARkwX6R3O0PCDEzRlfaQ",
    // 	 "token_type": "Bearer",
    // 	 "expires_in": 3600,
    // 	 "refresh_token": "1/r_2c_7jddspcdfesrrfKqfXtqo08D6Q-gUU0DsdfVMsx0c"
    // 	}
    // 
    console.log("OAuth2 authorization granted!");
    console.log("Access Token = " + oauth2.AccessToken);

}

chilkatExample();