Skip to main content

NestJS In-Memory Cache

In this article, we are going to explore the steps to implement the In-Memory Cache in the NestJS application.

Caching can significantly improve application performance and its scalability by reducing the workload to generate the content. In-Memory cache creates within the server application memory. Since it uses application memory it delivers content more fastly. But if our application runs on multiple nodes or multiple servers then the in-memory cache can't be shared between the nodes or server each will maintains its own in-memory cache.

Create A Sample NestJS Application:

Let's understand step by step implementation authentication in NestJs application, so let's begin our journey by creating a sample application.
Command To Install CLI:
npm i -g @nestjs/cli
Command To Create NestJS App:
nest new your_project_name

Install Cache Npm Packages:

NestJS Cache NPM Packages:
npm install cache-manager
npm install -D @types/cache-manager

Register CacheModule:

Now let's register the CacheModule in the AppModule file.
src/app.module.ts:
import { Module,  CacheModule } from '@nestjs/common';
// existing code hidden for display purpose

@Module({
  imports: [CacheModule.register()]
})
export class AppModule {}
  • Register the 'CacheModule' with empty configuration that means its automatically uses the In-memory cache.If we want to use external cache store like redis then we have to pass configuration values to the 'register()' method. The 'CacheModule' loads from the '@nestjs/common'.

Inject CacheManager:

Now to communicate with the cache store or memory we need to inject into our controller.
src/app.controller.ts:
import { Controller, Inject, CACHE_MANAGER } from '@nestjs/common';
import {Cache} from 'cache-manager';

@Controller()
export class AppController {
  constructor(@Inject(CACHE_MANAGER) private cacheManager: Cache) {}
}
  • The 'Cache' is the type of our cache store that loads from the 'cache-manager' library. The 'CACHE_MANAGER' is lookup key for the provider to be injected and this loads from the '@nestjs/common' library.

Get And Set Methods Of Cache Store:

The 'Set' method to save the data into our In-memory cache. The 'Get' method is to fetch data from the In-memory cache.

Let's create sample endpoint that saves and fetches the simple string from the In-Memory cache store.
src/app.controller.cs:
import { Controller, Get, Inject, CACHE_MANAGER } from '@nestjs/common';
import {Cache} from 'cache-manager';
@Controller()
export class AppController {

  myfakeDB:string ="naveen";

  constructor(@Inject(CACHE_MANAGER) private cacheManager: Cache) {}

  @Get('in-memory')
  async getFromMemoryCache(){
    let value = await this.cacheManager.get('name');
    if(value){
      return{
        dataFrom: 'In-memory Cache',
        name: value
      }
    }
    await this.cacheManager.set('name', this.myfakeDB, {ttl: 300} );
    return {
      dataFrom: 'Fake Database',
      name: this.myfakeDB
    }
  }
}
  • (Line: 6) The 'myfakeDB' variable let's assume like fetching the value from the database.
  • (Line: 12) The 'get()' method fetches the data saved in the In-memory cache store with respect to the 'key' passed to it. So here we are to check whether our data is available in the In-Memory cache or not.
  • (Line: 13-18) Return the response data from the In-memory cache.
  • (Line: 19) The 'set()' method to save the data from our application to the In-memory cache-store. While saving data we are passing our data expiration time as 300sec(5 minutes).
  • (Line: 20-23) Return the response data from the database(in our sample a fake data).
In the previous example, we stored simple string, but in real-time application mostly we have to store complex data. Our 'set' and 'get' methods support storing complex objects as well.
src/shared/models/Person.ts:
export interface Person {
  name: string;
  email: string;
}
Now let's update the endpoint to save the object type data into the In-Memory cache.
src/app.controller.ts:
import { Controller, Get, Inject, CACHE_MANAGER } from '@nestjs/common';
import {Cache} from 'cache-manager';
import { Person } from './shared/models/person';

@Controller()
export class AppController {

  myfakeDB:Person = {
    name:"naveen",
    email:"naveen@gmail.com"
  };

  constructor(@Inject(CACHE_MANAGER) private cacheManager: Cache) {}

  @Get('in-memory')
   async getFromMemoryCache(){
    let value = await this.cacheManager.get<Person>('user-info');
    if(value){
      return {
        dataFrom: 'From Cache',
        userInfo: value
      }
    }

    await this.cacheManager.set<Person>('user-info',this.myfakeDB, {ttl: 300});
    return {
      dataFrom: 'My Fake Database',
      userInfo: this.myfakeDB
    }
  }
}
Here we can observe the saving of complex objects into the In-Memory cache.

Del And Reset Methods Of Cache-Store:

The cache store provides the method 'del('key')'  used to delete the record from the cache.
await this.cacheManager.del('your_key_to_delte');
The cache store provides the method 'reset()' used to clear the entire In-Memory cache.
await this.cacheManager.reset()
That's all about some core features to implement an In-Memory cache in the NestJS application.

Support Me!
Buy Me A Coffee PayPal Me

Wrapping Up:

Hopefully, I think this article delivered some useful information on In-Memory Cache in the NestJS application. I love to have your feedback, suggestions, and better techniques in the comment section below.

Follow Me:

Comments

  1. Thanks a lot. saved me a big time

    ReplyDelete
  2. Thanks for the article interesting I am implementing nestjs in our organization and found your article useful I do have an issue and hoping you could help i am getting a promise object returned when I do a get after a set

    ReplyDelete

Post a Comment

Popular posts from this blog

Angular 14 Reactive Forms Example

In this article, we will explore the Angular(14) reactive forms with an example. Reactive Forms: Angular reactive forms support model-driven techniques to handle the form's input values. The reactive forms state is immutable, any form filed change creates a new state for the form. Reactive forms are built around observable streams, where form inputs and values are provided as streams of input values, which can be accessed synchronously. Some key notations that involve in reactive forms are like: FormControl - each input element in the form is 'FormControl'. The 'FormControl' tracks the value and validation status of form fields. FormGroup - Track the value and validate the state of the group of 'FormControl'. FormBuilder - Angular service which can be used to create the 'FormGroup' or FormControl instance quickly. Form Array - That can hold infinite form control, this helps to create dynamic forms. Create An Angular(14) Application: Let'

.NET 7 Web API CRUD Using Entity Framework Core

In this article, we are going to implement a sample .NET 7 Web API CRUD using the Entity Framework Core. Web API: Web API is a framework for building HTTP services that can be accessed from any client like browser, mobile devices, and desktop apps. In simple terminology API(Application Programming Interface) means an interface module that contains programming functions that can be requested via HTTP calls either to fetch or update data for their respective clients. Some of the Key Characteristics of API: Supports HTTP verbs like 'GET', 'POST', 'PUT', 'DELETE', etc. Supports default responses like 'XML' and 'JSON'. Also can define custom responses. Supports self-hosting or individual hosting, so that all different kinds of apps can consume it. Authentication and Authorization are easy to implement. The ideal platform to build the REST full services. Install The SQL Server And SQL Management Studio: Let's install the SQL server on our l

ReactJS(v18) JWT Authentication Using HTTP Only Cookie

In this article, we will implement the ReactJS application authentication using the HTTP-only cookie. HTTP Only Cookie: In a SPA(Single Page Application) Authentication JWT token either can be stored in browser 'LocalStorage' or in 'Cookie'. Storing the JWT token inside of the cookie then the cookie should be HTTP Only. The HTTP-ONly cookie nature is that it will be only accessible by the server application. Client apps like javascript-based apps can't access the HTTP-Only cookie. So if we use the authentication with HTTP-only JWT cookie then we no need to implement the custom logic like adding authorization header or storing token data, etc at our client application. Because once the user authenticated cookie will be automatically sent to the server by the browser on every API call. Authentication API: To authenticate our client application with JWT HTTP-only cookie, I developed a NetJS(which is a node) Mock API. Check the GitHub link and read the document on G

.NET6 Web API CRUD Operation With Entity Framework Core

In this article, we are going to do a small demo on AspNetCore 6 Web API CRUD operations. What Is Web API: Web API is a framework for building HTTP services that can be accessed from any client like browser, mobile devices, desktop apps. In simple terminology API(Application Programming Interface) means an interface module that contains a programming function that can be requested via HTTP calls to save or fetch the data for their respective clients. Some of the key characteristics of API: Supports HTTP verbs like 'GET', 'POST', 'PUT', 'DELETE', etc. Supports default responses like 'XML' and 'JSON'. Also can define custom responses. Supports self-hosting or individual hosting, so that all different kinds of apps can consume it. Authentication and Authorization are easy to implement. The ideal platform to build REST full services. Create A .NET6 Web API Application: Let's create a .Net6 Web API sample application to accomplish our

Angular 14 State Management CRUD Example With NgRx(14)

In this article, we are going to implement the Angular(14) state management CRUD example with NgRx(14) NgRx Store For State Management: In an angular application to share consistent data between multiple components, we use NgRx state management. Using NgRx state helps to avoid unwanted API calls, easy to maintain consistent data, etc. The main building blocks for the NgRx store are: Actions - NgRx actions represents event to trigger the reducers to save the data into the stores. Reducer - Reducer's pure function, which is used to create a new state on data change. Store - The store is the model or entity that holds the data. Selector - Selector to fetch the slices of data from the store to angular components. Effects - Effects deals with external network calls like API. The effect gets executed based the action performed Ngrx State Management flow: The angular component needs data for binding.  So angular component calls an action that is responsible for invoking the API call.  Aft

Angular 14 Crud Example

In this article, we will implement CRUD operation in the Angular 14 application. Angular: Angular is a framework that can be used to build a single-page application. Angular applications are built with components that make our code simple and clean. Angular components compose of 3 files like TypeScript File(*.ts), Html File(*.html), CSS File(*.cs) Components typescript file and HTML file support 2-way binding which means data flow is bi-directional Component typescript file listens for all HTML events from the HTML file. Create Angular(14) Application: Let's create an Angular(14) application to begin our sample. Make sure to install the Angular CLI tool into our local machine because it provides easy CLI commands to play with the angular application. Command To Install Angular CLI npm install -g @angular/cli Run the below command to create the angular application. Command To Create Angular Application ng new name_of_your_app Note: While creating the app, you will see a noti

Unit Testing Asp.NetCore Web API Using xUnit[.NET6]

In this article, we are going to write test cases to an Asp.NetCore Web API(.NET6) application using the xUnit. xUnit For .NET: The xUnit for .Net is a free, open-source, community-focused unit testing tool for .NET applications. By default .Net also provides a xUnit project template to implement test cases. Unit test cases build upon the 'AAA' formula that means 'Arrange', 'Act' and 'Assert' Arrange - Declaring variables, objects, instantiating mocks, etc. Act - Calling or invoking the method that needs to be tested. Assert - The assert ensures that code behaves as expected means yielding expected output. Create An API And Unit Test Projects: Let's create a .Net6 Web API and xUnit sample applications to accomplish our demo. We can use either Visual Studio 2022 or Visual Studio Code(using .NET CLI commands) to create any.Net6 application. For this demo, I'm using the 'Visual Studio Code'(using the .NET CLI command) editor. Create a fo

Part-1 Angular JWT Authentication Using HTTP Only Cookie[Angular V13]

In this article, we are going to implement a sample angular application authentication using HTTP only cookie that contains a JWT token. HTTP Only JWT Cookie: In a SPA(Single Page Application) Authentication JWT token either can be stored in browser 'LocalStorage' or in 'Cookie'. Storing JWT token inside of the cookie then the cookie should be HTTP Only. The HTTP-Only cookie nature is that it will be only accessible by the server application. Client apps like javascript-based apps can't access the HTTP-Only cookie. So if we use authentication with HTTP only JWT cookie then we no need to implement custom logic like adding authorization header or storing token data, etc at our client application. Because once the user authenticated cookie will be automatically sent to the server by the browser on every API call. Authentication API: To implement JWT cookie authentication we need to set up an API. For that, I had created a mock authentication API(Using the NestJS Se

ReactJS(v18) Authentication With JWT AccessToken And Refresh Token

In this article, we are going to do ReactJS(v18) application authentication using the JWT Access Token and Refresh Token. JSON Web Token(JWT): JSON Web Token is a digitally signed and secured token for user validation. The JWT is constructed with 3 important parts: Header Payload Signature Create ReactJS Application: Let's create a ReactJS application to accomplish our demo. npx create-react-app name-of-your-app Configure React Bootstrap Library: Let's install the React Bootstrap library npm install react-bootstrap bootstrap Now add the bootstrap CSS reference in 'index.js'. src/index.js: import 'bootstrap/dist/css/bootstrap.min.css' Create A React Component 'Layout': Let's add a React component like 'Layout' in 'components/shared' folders(new folders). src/components/shared/Layout.js: import Navbar from "react-bootstrap/Navbar"; import { Container } from "react-bootstrap"; import Nav from "react-boot

A Small Guide On NestJS Queues

NestJS Application Queues helps to deal with application scaling and performance challenges. When To Use Queues?: API request that mostly involves in time taking operations like CPU bound operation, doing them synchronously which will result in thread blocking. So to avoid these issues, it is an appropriate way to make the CPU-bound operation separate background job.  In nestjs one of the best solutions for these kinds of tasks is to implement the Queues. For queueing mechanism in the nestjs application most recommended library is '@nestjs/bull'(Bull is nodejs queue library). The 'Bull' depends on Redis cache for data storage like a job. So in this queueing technique, we will create services like 'Producer' and 'Consumer'. The 'Producer' is used to push our jobs into the Redis stores. The consumer will read those jobs(eg: CPU Bound Operations) and process them. So by using this queues technique user requests processed very fastly because actually