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angular rxjs 6 how to prevent duplicate http requests

Download 1M+ code from https://codegive.com/ad0203a angular rxjs 6: preventing duplicate http requests in angular applications, it's crucial to avoid making redundant http requests, as this can lead to performance degradation, unnecessary server load, and a poor user experience. rxjs, with its powerful operators, provides elegant solutions to manage and prevent these duplicate calls. this tutorial details several strategies using rxjs 6 to handle this common issue. *understanding the problem:* duplicate http requests typically occur when multiple components or services trigger the same api call simultaneously, perhaps due to user actions like rapid button clicks or concurrent data loading. without proper handling, each request is executed independently, wasting resources and potentially returning inconsistent data. *solutions using rxjs:* we'll explore three primary approaches using rxjs operators: 1. *`sharereplay()`:* this operator caches the results of the http request and replays them to subsequent subscribers. this is suitable when you expect multiple components to need the same data, and the data doesn't change frequently. 2. *`switchmap()`:* this operator cancels any in-flight http requests when a new one is initiated. this is ideal for scenarios where the latest data is always needed, and older requests are irrelevant. 3. *custom subject/behaviorsubject:* you can create a custom subject to manage the http requests, ensuring that only one request is in progress at any time. this offers the most control but requires more manual management. *code examples:* let's consider a simple angular service that fetches data from a rest api: *component usage:* now, let's see how to use these methods in a component: *explanation:* *`sharereplay(1)`:* this caches the last emitted value and replays it to new subscribers. the `1` specifies that only the last emitted value is cached. subsequent subscriptions receive the cached value immediately without triggering a new http reques ... #Angular #RxJS #numpy Angular RxJS 6 prevent duplicate requests HTTP requests debounce switchMap distinctUntilChanged service calls caching observable httpClient operator subscription management performance optimization request deduplication