Zig Requires Chilkat v10.1.2+

GeoOp OAuth2 Authorisation Code Grant (Public App)

See more OAuth2 Examples

Demonstrates how to get an access token for a GeoOp Third-Party Public Application using the Authorisation Code Grant flow. Zig

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

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

    const oauth2 = try chilkat.OAuth2.init();
    defer oauth2.deinit();

    // This should match the Site URL configured for your GeoOp (non-Server) Application, such as "http://localhost:3017/"
    oauth2.setListenPort(3017);

    oauth2.setAuthorizationEndpoint("https://login.geoop.com/oauth2/code");
    oauth2.setTokenEndpoint("https://login.geoop.com/oauth2/token");

    // Replace the client ID with an actual value.
    oauth2.setClientId("GEOOP-APPLICATION-ID");
    // The ClientSecret should remain empty for a GeoOp public application
    oauth2.setClientSecret("");

    // We need a few special settings for GeoOp
    oauth2.setScope("default");
    oauth2.setCodeChallenge(false);
    // Setting LocalHost equal to "none" prevents the "redirect_uri" query param from being sent in the initial HTTP request.
    // Note: The GeoOp Application should still have a redirect URL specified as "http://localhost:3017/", where the port
    // number matches the ListenPort above.
    oauth2.setLocalHost("none");

    // Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
    const url = oauth2.startAuth(alloc) catch {
        std.debug.print("{s}\n", .{try oauth2.getLastErrorText(alloc)});
        return;
    };

    // Launch the default browser on the system and navigate to the url.
    // The LaunchBrowser method was added in Chilkat v10.1.2.
    oauth2.launchBrowser(url) catch {
        std.debug.print("{s}\n", .{try oauth2.getLastErrorText(alloc)});
        return;
    };

    // Wait for the user to approve or deny authorization in the browser.
    var num_ms_waited: i32 = 0;
    while ((num_ms_waited < 90000) and (oauth2.getAuthFlowState() < 3)) {
        oauth2.sleepMs(100);
        num_ms_waited = num_ms_waited + 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.getAuthFlowState() < 3) {
        oauth2.cancel() catch {};
        std.debug.print("No response from the browser!\n", .{});
        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.getAuthFlowState() == 5) {
        std.debug.print("OAuth2 failed to complete.\n", .{});
        std.debug.print("{s}\n", .{try oauth2.getFailureInfo(alloc)});
        return;
    }

    if (oauth2.getAuthFlowState() == 4) {
        std.debug.print("OAuth2 authorization was denied.\n", .{});
        std.debug.print("{s}\n", .{try oauth2.getAccessTokenResponse(alloc)});
        return;
    }

    if (oauth2.getAuthFlowState() != 3) {
        std.debug.print("Unexpected AuthFlowState:{d}\n", .{oauth2.getAuthFlowState()});
        return;
    }

    std.debug.print("OAuth2 authorization granted!\n", .{});
    std.debug.print("Access Token = {s}\n", .{try oauth2.getAccessToken(alloc)});

    // Save the entire JSON response, which includes the access token, for future calls.
    // The JSON AccessTokenResponse looks like this:
    // {"access_token":"e6dqdG....mzjpT04w==","token_type":"Bearer","expires_in":2592000,"owner_id":984236}

    const fac = try chilkat.FileAccess.init();
    defer fac.deinit();
    fac.writeEntireTextFile("qa_data/tokens/geoop.json", try oauth2.getAccessTokenResponse(alloc), "utf-8", false) catch {};

    std.debug.print("Success.\n", .{});
}