| // An internal module to expose the "waitUntil" API to Edge SSR and Edge Route Handler functions. | |
| // This is highly experimental and subject to change. | |
| // We still need a global key to bypass Webpack's layering of modules. | |
| const GLOBAL_KEY = Symbol.for('__next_internal_waitUntil__') | |
| const state: { | |
| waitUntilCounter: number | |
| waitUntilResolve: () => void | |
| waitUntilPromise: Promise<void> | null | |
| } = | |
| // @ts-ignore | |
| globalThis[GLOBAL_KEY] || | |
| // @ts-ignore | |
| (globalThis[GLOBAL_KEY] = { | |
| waitUntilCounter: 0, | |
| waitUntilResolve: undefined, | |
| waitUntilPromise: null, | |
| }) | |
| // No matter how many concurrent requests are being handled, we want to make sure | |
| // that the final promise is only resolved once all of the waitUntil promises have | |
| // settled. | |
| function resolveOnePromise() { | |
| state.waitUntilCounter-- | |
| if (state.waitUntilCounter === 0) { | |
| state.waitUntilResolve() | |
| state.waitUntilPromise = null | |
| } | |
| } | |
| export function internal_getCurrentFunctionWaitUntil() { | |
| return state.waitUntilPromise | |
| } | |
| export function internal_runWithWaitUntil<T>(fn: () => T): T { | |
| const result = fn() | |
| if ( | |
| result && | |
| typeof result === 'object' && | |
| 'then' in result && | |
| 'finally' in result && | |
| typeof result.then === 'function' && | |
| typeof result.finally === 'function' | |
| ) { | |
| if (!state.waitUntilCounter) { | |
| // Create the promise for the next batch of waitUntil calls. | |
| state.waitUntilPromise = new Promise<void>((resolve) => { | |
| state.waitUntilResolve = resolve | |
| }) | |
| } | |
| state.waitUntilCounter++ | |
| return result.finally(() => { | |
| resolveOnePromise() | |
| }) | |
| } | |
| return result | |
| } | |