node-powertools - npm Package Compare versions

Comparing version 1.3.0 to 1.4.0

dist/index.js

@@ -114,2 +114,4 @@ (function (root, factory) {
   // https://github.com/sindresorhus/p-state/blob/main/index.js
+  // https://stackoverflow.com/questions/30564053/how-can-i-synchronously-determine-a-javascript-promises-state
+  // https://dev.to/xnimorz/101-series-promises-2-how-to-get-current-promise-status-and-build-your-own-promise-queue-18j8
   Powertools.getPromiseState = function (promise) {
@@ -140,2 +142,34 @@ util = util || require('util');
 
+  Powertools.waitForPendingPromises = function (promises, options) {
+    return new Promise(function(resolve, reject) {
+      // Fix promises
+      promises = Powertools.arrayify(promises);
+
+      // Fix options
+      options = options || {};
+      options.max = typeof options.max === 'undefined' ? 10 : options.max;
+      options.timeout = typeof options.timeout === 'undefined' ? 60000 : options.timeout;
+
+      // Poll for pending promises
+      Powertools.poll(() => {
+        const pending = promises.filter((promise) => Powertools.getPromiseState(promise) === 'pending');
+
+        // Stop and wait
+        if (pending.length >= options.max) {
+          // console.log(`Waiting for ${pending.length} pending promises to finish...`);
+          return false;
+        }
+
+        // We can continue
+        return true;
+      }, { interval: 100, timeout: options.timeout })
+      .then(() => {
+        return resolve();
+      })
+      .catch((e) => {
+        return reject(new Error('Timed out waiting for pending promises to finish'));
+      })
+    });
+  }
+
   Powertools.queue = function (options) {
@@ -142,0 +176,0 @@ return new FunctionQueue(options);

package.json

 {
   "name": "node-powertools",
-  "version": "1.3.0",
+  "version": "1.4.0",
   "description": "Powerful assistive functions for Node and Browser environments.",
@@ -5,0 +5,0 @@ "main": "dist/index.js",

README.md

@@ -133,2 +133,20 @@ <p align="center">
 
+### powertools.waitForPendingPromises(promises, options)
+Wait for `options.max` promises to resolve before continuing. This is useful for when you have a large number of promises and you want to limit the number of concurrent promises that are running at any given time. This promise **rejects** if the `options.timeout` is reached.
+
+This method depends on `util` from Node.js, so it will not work in the browser.
+```js
+const promises = [
+  powertools.wait(1000),
+  powertools.wait(2000),
+  powertools.wait(3000),
+];
+
+console.log('Starting processing', promises);
+
+await powertools.waitForPendingPromises(promises, {max: 2, timeout: 2000});
+
+console.log('Finished processing', promises);
+```
+
 ### powertools.escape(str)
@@ -135,0 +153,0 @@ Add the escape character `\` before any character in `str` that needs to be escaped for a `RegExp`.

src/index.js

@@ -114,2 +114,4 @@ (function (root, factory) {
   // https://github.com/sindresorhus/p-state/blob/main/index.js
+  // https://stackoverflow.com/questions/30564053/how-can-i-synchronously-determine-a-javascript-promises-state
+  // https://dev.to/xnimorz/101-series-promises-2-how-to-get-current-promise-status-and-build-your-own-promise-queue-18j8
   Powertools.getPromiseState = function (promise) {
@@ -140,2 +142,34 @@ util = util || require('util');
 
+  Powertools.waitForPendingPromises = function (promises, options) {
+    return new Promise(function(resolve, reject) {
+      // Fix promises
+      promises = Powertools.arrayify(promises);
+
+      // Fix options
+      options = options || {};
+      options.max = typeof options.max === 'undefined' ? 10 : options.max;
+      options.timeout = typeof options.timeout === 'undefined' ? 60000 : options.timeout;
+
+      // Poll for pending promises
+      Powertools.poll(() => {
+        const pending = promises.filter((promise) => Powertools.getPromiseState(promise) === 'pending');
+
+        // Stop and wait
+        if (pending.length >= options.max) {
+          // console.log(`Waiting for ${pending.length} pending promises to finish...`);
+          return false;
+        }
+
+        // We can continue
+        return true;
+      }, { interval: 100, timeout: options.timeout })
+      .then(() => {
+        return resolve();
+      })
+      .catch((e) => {
+        return reject(new Error('Timed out waiting for pending promises to finish'));
+      })
+    });
+  }
+
   Powertools.queue = function (options) {
@@ -142,0 +176,0 @@ return new FunctionQueue(options);

test/test.js

@@ -65,2 +65,24 @@ const package = require('../package.json');
 
+  describe('.waitForPendingPromises()', () => {
+    describe('promise', () => {
+      // This test should fail because it waits for two promises that never complete
+      it('promise (pending) => string (resolved) - should fail', () => {
+        // Create an array of promises that never resolve
+        const promises = [new Promise(() => {}), new Promise(() => {})];
+
+        // This should reject because the promises never resolve
+        return assert.rejects(powertools.waitForPendingPromises(promises, 2, 1000));
+      });
+
+      // This test should pass because the promises do complete
+      it('promise (pending) => string (resolved) - should pass', () => {
+        // Create an array of promises that resolve after 1 second
+        const promises = [new Promise(resolve => setTimeout(resolve, 1000)), new Promise(resolve => setTimeout(resolve, 1000))];
+
+        // This should not reject because the promises do resolve
+        return assert.doesNotReject(powertools.waitForPendingPromises(promises, 2));
+      });
+    });
+  });
+
   describe('.getKeys()', () => {
@@ -67,0 +89,0 @@

No alert changes

Improved metrics

Total package byte prevSize

68059

increased by7.88%

Number of package files

8

increased by33.33%

Lines of code

1494

increased by7.02%

Number of lines in readme file

303

increased by6.32%

No dependency changes