Welcome to promise-placeholder 👋

> Creates a placeholder object which can be used to keep functions which can be called in parallel and post execution, the values will be assigned at proper places! ### 🏠 [Homepage](https://github.com/prkeshri/node-promise-placeholder#readme) ## Install ```sh npm install ``` ## PromisePlaceholder Creates a placeholder object which can be used to keep functions which can be called in parallel and post execution, the values will be assigned at proper places! **Kind**: global constant **Notes**: 1. All the methods of async library are mapped with exec followed by first letter uppercase method name.
For example:
```async.parallelLimit``` will be used when ```pp.execParallelLimit(2)``` will be called // This will make 2 concurrent calls at a time
... etc 2. exec is short for execParallel which uses async.parallel
**Example** ```js // Consider the following scenario where we need complete data on teams. // We need the data at the respective points by calling the api. (get...FromApi are async functions that make http call to some server which outputs the desired array!) const PromisePlaceholder = require('promise-placeholder'); const pp = new PromisePlaceholder; const obj = { data1: pp({ teams: async () => getTeamsFromApi(), playersInfo: pp({ active: async () => getActivePlayersFromApi(), retired: async () => getRetiredPlayersFromApi(), joinedIn2007: async () => getPlayersFromApi(2007), joinedLater: pp({ 2008: async () => getJoinedLaterThanFromApi(2007) }) }) }) } // Note: pp() -> This call collects all the keys with value as a function in the object. It DOES NOT iterate deep, that's the reason pp() is should be called on every object which has a function value in any key which should be included in a parallel call. // In case of deep-iteration is deserved, see [collect](#PromisePlaceholder+collect) // Now, we need all the async calls to execute and the value to be set at the respective places. await pp.exec(); // By default executes async.parallel(); ,, other async.method can be used as an uppercase version (Example below) // By default, the above outputs the result of async[method] call but this will ideally not be required and can be ignored! // Troper values will be placed in obj itself. console.log(obj); // will log: { data1: { teams: ['team1','team2'], playersInfo: { active: ['activeplayer1', 'activeplayer2'], retired: , joinedIn2007: , joinedLater: { 2008: } } } } ``` * [PromisePlaceholder](#PromisePlaceholder) * _instance_ * [.setReviver(reviver)](#PromisePlaceholder+setReviver) * [.getResults()](#PromisePlaceholder+getResults) ⇒ * [.getRefs()](#PromisePlaceholder+getRefs) ⇒ * [.size()](#PromisePlaceholder+size) ⇒ * [.exec()](#PromisePlaceholder+exec) ⇒ * [.collect(obj)](#PromisePlaceholder+collect) ⇒ [PromisePlaceholder](#PromisePlaceholder) * _static_ * [.withAsync](#PromisePlaceholder.withAsync) ### promisePlaceholder.setReviver(reviver) Sets a reviver otherwise plain assignment is used. Can be used to revive manually! **Kind**: instance method of [PromisePlaceholder](#PromisePlaceholder) | Param | Type | Description | | --- | --- | --- | | reviver | function \| string | If reviver = 'ignore', the revival will be skipped and the values need to be revived manually | ### promisePlaceholder.getResults() ⇒ Returns results array of execution **Kind**: instance method of [PromisePlaceholder](#PromisePlaceholder) **Returns**: results ### promisePlaceholder.getRefs() ⇒ Returns internal references **Kind**: instance method of [PromisePlaceholder](#PromisePlaceholder) **Returns**: refs ### promisePlaceholder.size() ⇒ **Kind**: instance method of [PromisePlaceholder](#PromisePlaceholder) **Returns**: Length of current of functions in the queue ### promisePlaceholder.exec() ⇒ Calls async.parallel and stores the values at the respective places! **Kind**: instance method of [PromisePlaceholder](#PromisePlaceholder) **Returns**: Result of async.parallel (may be discarded) ### promisePlaceholder.collect(obj) ⇒ [PromisePlaceholder](#PromisePlaceholder) Instead of calling the promisePlaceholder at every step, it may be desirable to deep iterate the object and collect all the functions! **Kind**: instance method of [PromisePlaceholder](#PromisePlaceholder) | Param | Type | | --- | --- | | obj | Object | **Example** ```js // In the example for [Placeholder](Placeholder), instead of wrapping every object having a promise inside a pp() call, // just call once like: const obj = { data1: { teams: async () => getTeamsFromApi(), playersInfo: { active: async () => getActivePlayersFromApi(), retired: async () => getRetiredPlayersFromApi(), joinedIn2007: async () => getPlayersFromApi(2007), joinedLater: { 2008: async () => getJoinedLaterThanFromApi(2007) } } } } // Now: await (new PromisePlaceholder()).collect(obj).exec(); After await resumes, obj will have all the values instead of functions! ``` ### PromisePlaceholder.withAsync Ability to pass custom async library such as another version of async or any other library. Will map that libraries method instead of async as above **Kind**: static property of [PromisePlaceholder](#PromisePlaceholder) **Example** ```js // Instead of new PromisePlaceholder //(See below), new (PromisePlaceholder.withAsync(customAsyncOrOtherLib)) // The outer brackets are necessary ``` * * * ## Run tests ```sh npm run test ``` ## Author 👤 **Praveen Ranjan Keshri** * Github: [@prkeshri](https://github.com/prkeshri) * LinkedIn: [@prkeshri](https://linkedin.com/in/prkeshri) ## 🤝 Contributing Contributions, issues and feature requests are welcome!
Feel free to check [issues page](https://github.com/prkeshri/node-promise-placeholder/issues). ## Show your support Give a ⭐️ if this project helped you! *** _This README was generated with ❤️ by [readme-md-generator](https://github.com/kefranabg/readme-md-generator)_