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Split async hook bootstrap logic
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mhofman committed Mar 17, 2022
1 parent 6230ae9 commit 96c6676
Showing 1 changed file with 37 additions and 39 deletions.
76 changes: 37 additions & 39 deletions packages/init/node-async_hooks.js
Original file line number Diff line number Diff line change
Expand Up @@ -49,48 +49,37 @@ const findAsyncSymbolsFromAsyncResource = () => {
// To get the `destroyed` symbol installed on promises by async_hooks,
// the only option is to create and enable an AsyncHook.
// Different versions of Node handle this in various ways.
const findAsyncSymbolsFromPromiseCreateHook = () => {
const bootstrapData = [];

{
const bootstrapHookData = [];
const bootstrapHook = createHook({
init(asyncId, type, triggerAsyncId, resource) {
if (type !== 'PROMISE') return;
// process._rawDebug('Bootstrap', asyncId, triggerAsyncId, resource);
bootstrapHookData.push({ asyncId, triggerAsyncId, resource });
},
destroy(_asyncId) {
// Needs to be present to trigger the addition of the destroyed symbol
},
});
const getPromiseFromCreateHook = () => {
const bootstrapHookData = [];
const bootstrapHook = createHook({
init(asyncId, type, triggerAsyncId, resource) {
if (type !== 'PROMISE') return;
// process._rawDebug('Bootstrap', asyncId, triggerAsyncId, resource);
bootstrapHookData.push({ asyncId, triggerAsyncId, resource });
},
destroy(_asyncId) {
// Needs to be present to trigger the addition of the destroyed symbol
},
});

bootstrapHook.enable();
// Use a never resolving promise to avoid triggering settlement hooks
const trigger = new Promise(() => {});
bootstrapHook.disable();
bootstrapHook.enable();
// Use a never resolving promise to avoid triggering settlement hooks
const trigger = new Promise(() => {});
bootstrapHook.disable();

// In some versions of Node, async_hooks don't give access to the resource
// itself, but to a "wrapper" which is basically hooks metadata for the promise
const promisesData = bootstrapHookData.filter(
({ resource }) => Promise.resolve(resource) === resource,
);
const { length } = promisesData;
if (length > 1) {
// process._rawDebug('Found multiple potential candidates');
}

const promiseData = promisesData.find(
({ resource }) => resource === trigger,
);
if (promiseData) {
bootstrapData.push(promiseData);
} else if (length) {
// process._rawDebug('No candidates matched');
}
// In some versions of Node, async_hooks don't give access to the resource
// itself, but to a "wrapper" which is basically hooks metadata for the promise
const promisesData = bootstrapHookData.filter(
({ resource }) => Promise.resolve(resource) === resource,
);
const { length } = promisesData;
if (length > 1) {
// process._rawDebug('Found multiple potential candidates');
}

if (bootstrapData.length) {
const promiseData = promisesData.find(({ resource }) => resource === trigger);

if (promiseData) {
// Normally all promise hooks are disabled in a subsequent microtask
// That means Node versions that modify promises at init will still
// trigger our proto hooks for promises created in this turn
Expand All @@ -101,8 +90,17 @@ const findAsyncSymbolsFromPromiseCreateHook = () => {
const resetHook = createHook({});
resetHook.enable();
resetHook.disable();
} else if (length) {
// process._rawDebug('No candidates matched');
}
return promiseData;
};

const findAsyncSymbolsFromPromiseCreateHook = () => {
const bootstrapPromise = getPromiseFromCreateHook();

const { asyncId, triggerAsyncId, resource } = bootstrapData.pop();
if (bootstrapPromise) {
const { asyncId, triggerAsyncId, resource } = bootstrapPromise;
const symbols = Object.getOwnPropertySymbols(resource);
// const { length } = symbols;
let found = 0;
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