Microsoft 365 / Outlook adapter

What you configure

createMicrosoft365Adapter

Supply a runtime access-token provider and optional calendarId.

timeZone / timeZoneMap

Choose display-zone behavior and map uncommon Windows time-zone identifiers.

delta cursor

Retain the provider's delta link together with the prior remote snapshot.

Integration code example

1. Obtain customer-managed Microsoft authorization separately from the WTS entitlement.
2. Create the adapter, pull the required range, and inspect normalized event metadata.
3. Reconcile local/remote changes and apply intended writes through your application's sync workflow.

Copy this TypeScript into your application, not the browser console. Replace YOUR_WTS_LICENSE_KEY with an entitlement issued for your deployment origin. A WTS license is not a Google, Microsoft or CalDAV credential. These examples are documentation only and never execute on this page.

npm install @wts-calendar/core

import { verifyCalendarLicense } from '@wts-calendar/core';
import { PremiumCalendarInteroperability } from '@wts-calendar/core/premium-interoperability';
import type {
  CalendarSynchronizationRequest,
  CalendarInteropMutation,
} from '@wts-calendar/core/premium-interoperability';
const license = await verifyCalendarLicense('YOUR_WTS_LICENSE_KEY');
const interoperability = new PremiumCalendarInteroperability({ license });

// Call after your application obtains an authorized session.
export function connectOutlook(getAccessToken: () => string | Promise<string>) {
  const adapter = interoperability.createMicrosoft365Adapter({
    accessToken: getAccessToken, // Default calendar; optionally supply calendarId.
    timeZone: 'UTC',
  });
  return {
    // Initial sync: omit cursor. For deltas, supply the retained remoteBase snapshot.
    preview: (request: CalendarSynchronizationRequest) =>
      interoperability.synchronize(adapter, {
        ...request,
        conflictPolicy: 'manual',
        push: false,
      }),
    // Call only after the user resolves conflicts and approves the mutation plan.
    commit: (mutations: readonly CalendarInteropMutation[], signal?: AbortSignal) =>
      adapter.push(mutations, signal ? { signal } : {}),
  };
}

// Example call in your session handler (do not use the WTS key as an OAuth token):
// const connection = connectOutlook(getAccessToken);
// const plan = await connection.preview({
//   start: '2026-09-01T00:00:00Z', end: '2026-10-01T00:00:00Z',
//   base: lastCommonEvents, local: currentEvents,
// });
// Show plan.reconciliation.conflicts and plan.mutations in your UI.
// After approval, await connection.commit(approvedMutations).
// Pull again and retain the fresh remote IDs/ETags, cursor and common base.

Application responsibilities

Supply getAccessToken from your own OAuth connection. Use a read/write calendar grant, keep access tokens in memory, and handle expiration or revocation. Never put a client secret or refresh token into browser code.

Start with the last common event base and current local events. On incremental pulls, retain the complete remoteBase snapshot as well as the cursor. A delta response alone is not a full snapshot.

Preview does not write to the provider. Resolve every manual conflict before committing reviewed mutations; catch network and ETag conflict errors and refresh instead of blindly overwriting. Re-pull after successful writes before updating sync state.

The package does not schedule background sync, obtain OAuth consent, or persist session state. Disconnect and abort pending requests when the user signs out.

Provide timeZoneMap when your tenant returns a Windows time-zone name that is not built into the adapter.

Behavior and lifecycle

• The adapter maps deletions, cancellations, all-day events, and supported event metadata.
• Create, update, and delete operations retain conditional version handling through ETags.