Closer/functions/src/options.ts

import { setGlobalOptions } from 'firebase-functions/v2'

/**
 * Global 2nd-gen options for every v2 function in this codebase.
 *
 * region: pinned to us-central1 — the Android client calls FirebaseFunctions.getInstance() with
 *   no region override (di/SecurityModule.kt, data/remote/FirestoreAnswerDataSource.kt), so the
 *   callables MUST live in us-central1 or every install breaks. Do not change without also
 *   pinning the client.
 * maxInstances: a runaway-bill guardrail AND a Cloud Run quota constraint. Each 2nd-gen function
 *   is a Cloud Run service, and the project's regional "total CPU allocation" quota is charged as
 *   the SUM of (maxInstances x vCPU) across every function. With ~34 v2 functions and a new
 *   project's default quota (~560 vCPU in us-central1), this must stay low or deploys fail with
 *   "Quota exceeded for total allowable CPU per project per region". 5 x 34 = 170, well under.
 *   For production: request a Cloud Run CPU quota increase (console → IAM & Admin → Quotas) and
 *   raise this. ~80 concurrent requests per instance means 5 instances still serves ~400 in flight.
 *
 * This module is imported FIRST in index.ts so these options are set before any v2 function is
 * defined. It has no effect on the one v1 holdout (onUserDelete), which keeps its own defaults.
 */
setGlobalOptions({ region: 'us-central1', maxInstances: 5 })

/** Region constant for any per-function override that ever needs to pin it explicitly. */
export const REGION = 'us-central1'