Zig

Decode Microsoft Graph ID Token

See more Microsoft Graph Examples

Demonstrates how to decode a Microsoft Graph ID token. Zig

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

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

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

    // This example loads an id_token and decodes it.

    // Our Microsoft Graph OAuth2 token looks like this:

    // {
    //   "token_type": "Bearer",
    //   "scope": "openid profile User.ReadWrite Mail.ReadWrite Mail.Send Files.ReadWrite User.Read Calendars.ReadWrite Group.ReadWrite.All",
    //   "expires_in": 3600,
    //   "ext_expires_in": 3600,
    //   "access_token": "EwCQA8l6...0HhMKYwC",
    //   "refresh_token": "MCWulIvzi2yD0S...igEFn51mqcByhZtAJg",
    //   "id_token": "eyJ0eXAiOiJKV1...Q7lRDaR-7A",
    //   "expires_on": "1562862714"
    // }

    const json_token = try chilkat.JsonObject.init();
    defer json_token.deinit();
    json_token.loadFile("qa_data/tokens/microsoftGraph.json") catch {
        std.debug.print("Failed to load the JSON file...\n", .{});
        return;
    };

    // Use Chilkat's JWT API to examine the id_token..
    const jwt = try chilkat.Jwt.init();
    defer jwt.deinit();
    const id_token = try json_token.stringOf(alloc, "id_token");

    // Extract the JOSE header..
    const jose = try jwt.getHeader(alloc, id_token);

    const json_header = try chilkat.JsonObject.init();
    defer json_header.deinit();
    json_header.load(jose) catch {};
    json_header.setEmitCompact(false);
    std.debug.print("{s}\n", .{try json_header.emit(alloc)});

    // The JOSE header looks like this:

    // {
    //   "typ": "JWT",
    //   "alg": "RS256",
    //   "kid": "1LTMzakihiRla_8z2BEJVXeWMqo"
    // }

    const claims = try jwt.getPayload(alloc, id_token);

    const json_claims = try chilkat.JsonObject.init();
    defer json_claims.deinit();
    json_claims.load(claims) catch {};
    json_claims.setEmitCompact(false);
    std.debug.print("{s}\n", .{try json_claims.emit(alloc)});

    // The claims look like this:

    // {
    //   "ver": "2.0",
    //   "iss": "https://login.microsoftonline.com/9188040d-6c67-4c5b-b112-36a304b66dad/v2.0",
    //   "sub": "AAAAAAAAAAAAAAAAAAAAAHJFryd6Gydo-XtTd1nhUNQ",
    //   "aud": "18c456bd-db75-43fe-9724-9e5d821c68ff",
    //   "exp": 1562945513,
    //   "iat": 1562858813,
    //   "nbf": 1562858813,
    //   "name": "Matt Chilkat",
    //   "preferred_username": "matt@example.com",
    //   "oid": "00000000-0000-0000-3a33-fceb9b74cc15",
    //   "tid": "9188040d-6c67-4c5b-b112-36a304b66dad",
    //   "aio": "DfibJqKnWC1c0FS6G ... W6pvTrQuYzyq16ghY$"
    // }
    //

    // Use this online tool to generate parsing code from sample JSON:
    // Generate Parsing Code from JSON

    // Get each of the claims..
    _ = try json_claims.stringOf(alloc, "ver");
    _ = try json_claims.stringOf(alloc, "iss");
    _ = try json_claims.stringOf(alloc, "sub");
    _ = try json_claims.stringOf(alloc, "aud");
    _ = json_claims.intOf("exp");
    _ = json_claims.intOf("iat");
    _ = json_claims.intOf("nbf");
    _ = try json_claims.stringOf(alloc, "name");
    _ = try json_claims.stringOf(alloc, "preferred_username");
    _ = try json_claims.stringOf(alloc, "oid");
    _ = try json_claims.stringOf(alloc, "tid");
    _ = try json_claims.stringOf(alloc, "aio");
}