Guidewire Install & Auth

Guidewire Install & Auth

Overview

Authenticate a backend service to a Guidewire Cloud tenant using OAuth2 client credentials and operate the auth layer in production. This is not a hello-world walkthrough; it is the auth code your service runs at 3am when a token expires mid-batch, when a tenant admin rotates a scope, when a private CA renews a cert, and when on-call needs to swap a leaked secret without dropping in-flight requests.

The four production failures this skill prevents:

1. Token expiry storms — every request races to refresh, the Hub rate-limits the auth endpoint, the integration cascades to red.
2. Scope drift — a GCC admin removes a scope, every cached token starts returning 403, retrying does not help.
3. PKIX path building failed — JVM cannot validate the tenant's TLS chain because the private CA is not in the trust store; common when carriers front Cloud API with their own DLP appliance.
4. Secret rotation downtime — the active client secret is rotated and the old secret stops working before the new one is loaded; in-flight token refreshes fail until restart.

Prerequisites

• JDK 17 (Guidewire Cloud release 202503 and later)
• A registered Service Application in Guidewire Cloud Console (GCC) with Cloud API roles assigned per least privilege
• Network egress from your runtime to *.guidewire.net (runtime APIs) and gcc.guidewire.com (console only)
• A secret store the runtime can read at startup and on rotation signal (AWS Secrets Manager, GCP Secret Manager, HashiCorp Vault, or Kubernetes Secret with CSI driver)
• For private-CA tenants: the carrier's CA chain in PEM form

Instructions

Build the auth layer in this order. Each section solves one production failure mode; do not skip steps because the failure shows up in production, not in dev.

1. Implement the token-cache pattern below — proactive refresh, single-flight gate, JWT-based expiry.
2. Wire secret rotation to your secret store; do not commit secrets or bake them into images.
3. For private-CA tenants, install the trust store at the JVM/init-container layer.
4. Validate scope hardening on every refresh so drift fails fast, not on the next business call.

Token-cache pattern (production)

Tokens are short-lived, typically one hour. Reactive refresh on 401 is wrong: it doubles latency on the failing request and creates a thundering herd when many requests notice expiry simultaneously. Cache the token in-process and refresh proactively at 80% of TTL, behind a single-flight gate so concurrent refreshers serialize.

import jwt from "jsonwebtoken";

type Cached = { value: string; expiresAt: number };
let cached: Cached | null = null;
let inflight: Promise<string> | null = null;