Skip to main content

A CRUD Operation Demo On NestJS Using Azure Cosmos DB

In this article, we are going to implement  CRUD operations into the NestJS application using Azure Cosmos DB.

Azure Cosmos DB:

Azure Cosmos DB is a fully managed NoSQL database. NoSQL says data will be stored as a key/value JSON document. Cosmos DB provides 'High Availability' and 'Low Latency' for any application. Cosmos DB is very quick in response delivering, auto-scaling, effective auto failure management, etc.

Any existing application that works on different DBs can be easily migrated to Azure CosmosDB as it provides APIs for integration like 'SQL/Core API'(most recommended API, our demo uses this 'SQL/Core API'), 'MongoDB API', 'Cassandra API', 'Germlin API', 'Table API'.

Let's understand the structure of the Cosmos DB:
  • Create an Azure Cosmos Account with an appropriate subscription inside of the Azure portal.
  • After creating the Cosmos Account, we can manage the data of our account by creating 'Database', 'Containers', and items.
  • Azure Cosmos 'Containers' means a 'Collection' or 'Table' or 'Collection' based on our APIs like 'SQL/Core API', 'MongoDB API', 'Cassandra API', etc.
  • Container contains 'Items', 'Stored Procedure', 'user-defined functions', 'triggers', etc.
  • Items inside of the Container depend on its type which means if a container is 'Table' then items will be 'Rows', if a container is 'Collection' then items will be documents, etc.
Note: Cosmos DB means NoSQL stores data as key/value. But above we discussed 'Container' that can be 'Collection', 'Table', 'Graph', etc is a representation for querying the Cosmos DB by all supported APIs.

Partition Key: -  
  • Azure Cosmos DB uses partitioning to scale individual containers in a database to meet the performance needs of our application. 
  • While partitioning, the item in a container is divided into logical partitions. 
  • Logical partitions are formed based on the value of the partition key that is associated with each item in a container.
  •  All the items in the logical partition have the same partition key value.
  • For example, the 'country' property is made as to the partition key, then items with a country name like 'India' are stored in one logical partition, and items with a country name like 'Italy' store in one logical partition, and so on.
  • So it is always advisable to use the most common and unchangeable 'property' as a partition key to get more performance and to manage the Price to spend on CosmosDB consumption.
  • If your items contain no proper property to use as a 'partition' key then we can use the 'Id' property.

Why To Use Azure Cosmos DB:

  • High Availability
  • Low Latency
  • Effect cost management pays the service on use only
  • NoSQL Database
  • Easy migration from any backend to Azure Database.
  • Auto Scale Up
  • Auto Maintenance
  • Effective Global Distribution

Create Azure Cosmos DB:

Step1:
Signup with the azure portal and then log in to the Azure portal and navigate to the home page (https://portal.azure.com/#home). Then select 'Create A Resource'.

Step 2:
In the 'Create A Resource' page select 'Azure Cosmos DB'.

Step3:
In 'Select API option' page choose 'Core(SQL) - Recomended'

Step 4:
In 'Create Azure Cosmos DB Account - Core(SQL)', inside of the 'Basic' tab, enter the 'Project Details
(a) Select your subscription
(b) Create a new resource group. The resource Group acts as a container or folder to our Cosmos DB.
(c) Give Account Name, based on your account name domain will be created so make sure to give a proper name.
(d) Location, select your nearest location for azure hosting, you can leave the default as a quick start.
(e) Capacity mode can choose default.
(f) App Free Tier Discount, is a very wise choice to choose by learners.
(g) Limit total account throughput can choose the default
Step 5:
Remaining tabs like 'Global Distribution', 'Networking', 'Backup Policy', 'Encryption', 'Tags' can use default values. So click on 'Review + create' button directly.

Step6:
Finally, click on the 'Create' button to create an Azure Cosmos DB Account.

Step 7:
Click on the 'Go to resource' button.

Step 8:
(a) In the Azure Cosmos DB account, in left-hand side menu select 'Data Explorer'.
(b) Click on 'New Container'.
(c) In the container form let's give details
(d) Choose 'Create New'(for creating a new database in Azure Cosmos DB Account). Then specify the name of the database(database id). I will name my database as 'Vehicles'.
(e) The 'Share throughput across containers' choose default.
(f) The 'Database throughput' chooses to default i.e 'Auto Scale'.
(g) The 'Database Max RU/s' level default value. The 'Request Unit/second' calculates price.
(h) Specify the container id. For our demo let's define 'Car'. The container is like a 'Table'.
(i) The 'indexing' choose 'Auto'.
(j) The 'Partition key' value is one of the names of property of the documents we store. To this demo, my JSON document contains properties like 'id', 'make', and 'model'. I will use 'make' as my partition key for my demo.
(k) Finally click on the 'Ok' button. Then we can observe a Database like 'Vehicles', container like 'Car' get created. (Note: These database names, and container name will be used by our NestJS application)
Step 9:
Select our 'Vehicle' database then select our container 'Car', then select 'Items' then Cosmos DB window editor shows up. Then click on 'New Item', then add the sample item(document) we want to store, and then click on 'Save'.

Step 10:
Edit Filter drop-down to write SQL queries to fetch our items(document)

Step 11:
Now go to 'Key' left-hand side menu and copy the 'URL' and 'Primary Key' value we are going to use in our NestJs application.

Create A NestJS Application:

Let's create a NestJS application to accomplish our demo.
Command To Install NestJS CLI
npm i -g @nestjs/cli

Command To Create A NestJS App
nest new your_project_name

Install Required NPM Packages:

Let's install the required NPM packages.
npm install @azure/cosmos

npm i --save @nestjs/azure-database

Configure AzureCosmosDbModule:

Now let's configure AzureCosmmosDbModule into the AppModule.
src/app.module.ts:
import { AzureCosmosDbModule } from '@nestjs/azure-database';
import { Module } from '@nestjs/common';
// code hidden for display purpose
@Module({
  imports: [
    AzureCosmosDbModule.forRoot({
      dbName:"Vehicles",
      endpoint:"your_azrue_comosdb_url",
      key:"your_azure_cosmosdb_primary_key"
    }),
  ],
})
export class AppModule {}
  • Imported AzureCosmosDbModule from the '@nestjs/azure-database' library.
  • (Line: 7) Declare our Azure Cosmos DB database name to 'dbName'.
  • (Line: 8) Declare our Azure Cosmos DB URL to 'endpoint'.
  • (Line: 9) Declare our Azure Cosmos DB primary key to  'key'.

Create A New Module Like 'CarModule':

We have created a container like 'Car' in Azure Cosmos DB. So let's create a new module like 'CarModule', that deals with our 'Car' container in Azure Cosmos DB.

Let's run the below command to create the 'Car' Module
nest g mo car

Now let's create a type 'car.entitiy.ts' that represents our Azure Cosmos DB container.
nest g cl car/car.entity --flat --no-spec

Let's update our 'car.entity.ts' file as below.
src/car/car.entity.ts:
import { CosmosPartitionKey } from "@nestjs/azure-database";

@CosmosPartitionKey('make')
export class Car {
  id: string;
  make: string;
  model: string;
}
  • Here created our class as 'Car' name of the car must match with our Azure Cosmos DB container.
  • Here class properties like 'id', 'make', 'model' names must match with document properties of the Azure Cosmos DB container.
  • Here specific our partition key property with the help of  '@CosmosPartitionkey' attribute that loads from the '@nesjs/azure-database.'
Now configure our 'Car' entity into the 'CarModule'.
src/car/car.module.ts:
import { AzureCosmosDbModule } from '@nestjs/azure-database';
import { Module } from '@nestjs/common';
import { Car } from './car.entity';

@Module({
  imports: [AzureCosmosDbModule.forFeature([{ collection: 'Car', dto: Car }])],
  controllers: [CarController],
})
export class CarModule {}
  • (Line: 6) Defined the 'AzureCosmosDbModule.forFeature({})'. So 'forFeature()' will be registered in child modules like 'CarModule', 'forRoot()' will be registered in parent module like 'AppModule'. Here collection means name our Azure Cosmos DB container, the 'dto' need to provide our 'Car' type.

Create A New Controller Like 'CarController':

Let's create a new controller like 'CarController', run below command.
nest g co car
src/car/car.controller.ts:
import { Container } from '@azure/cosmos';
import { InjectModel } from '@nestjs/azure-database';
import { Controller } from '@nestjs/common';
import { Car } from './car.entity';

@Controller('car')
export class CarController {
  constructor(@InjectModel(Car) private readonly carContainer: Container) {}
}
  • Here injected the token like '@InjectModel(Car)' that loads from the '@nestjs/azure-database' and its type is 'Container' that loads from the '@azure/cosmos'.
Now let's create API a response model like 'car.dto.ts'
nest g cl car/car.dto --flat --no-spec
src/car/car.dto.ts:
export interface ICarDto {
  id: string;
  make: string;
  model: string;
}

Read Operation:

Let's implement the read operation by fetching all the items from the Azure Cosmos DB container.
src/car/car.controller.ts:
import {  Get } from '@nestjs/common';
import { ICarDto } from './car.dto';
import { Car } from './car.entity';

@Get('all')
async getCars() {
  var sqlQuery = 'select * from c';

  var consmosResults = await this.carContainer?.items
	  ?.query<Car>(sqlQuery)
	  .fetchAll();
  var fanal = consmosResults.resources.map<ICarDto>((value) => {
	  return {
		id: value.id,
		make: value.make,
		model: value.model,
	  };
  });
  return fanal;
}
  • (Line: 7) Here we defined a simple SQL query to fetch all the data. Here 'c' can be given any other character or string inside of the query.
  • (Line: 9-11) Here invoking the Azure Cosmos DB for fetching the items based on the query we framed.
  • (Line 12-19) Response from the Azure Cosmos DB is mapped with our response type 'ICarDto' and then returns the response.

Create Operation:

Let's implement create operation to save a new item into the container of the Azure Cosmos DB.
src/car/car.controller.ts:
import { Body,, Post } from '@nestjs/common';
import { ICarDto } from './car.dto';
import { Car } from './car.entity';

@Post('create')
async create(@Body() payload: ICarDto) {
var newCar = new Car();
newCar.id = '2';
newCar.make = payload.make;
newCar.model = payload.model;
var { resource } = await this.carContainer.items.create(newCar);
return {
  id: resource.id,
  make: resource.make,
  model: resource.model,
};
  • (Line: 7-10) Mapping our user payload to the 'Car'.
  • (Line: 11) Invoking the Azure Cosmos DB to save the new item into the container.
step 1:

step 2:

Update Operation:

Let's implement the update operation to update an item in the container at Azure Cosmos DB.
src/car/car.controller.ts:
import { Body, Put } from '@nestjs/common';
import { ICarDto } from './car.dto';
import { Car } from './car.entity';

@Put('update')
async update(@Body() payload:ICarDto){
var carToUpdate = new Car();
carToUpdate.id = payload.id;
carToUpdate.make = payload.make;
carToUpdate.model = payload.model;

var {resource} = await this.carContainer.items.upsert(carToUpdate);
return {
  id: resource.id,
  make: resource.make,
  model: resource.model,
};
}
  • (Line: 12) Invoking the Azure Cosmos DB to update the items inside of the container.
step 1:

step 2:

step 3:

Delete Operation:

Let's implement the delete operation to remove an item from the container of the Azure Cosmos DB.
src/car/car.controller.ts:
import { Delete, Query } from '@nestjs/common';

@Delete('remove')
async remove(@Query('id') id:string, @Query('partitionkey') partitionkey:string){
await this.carContainer.item(id, partitionkey).delete();
return "deleted";
}
  • Here to remove or delete an item depends on 'id' and 'partitonkey'(for our demo partition key value is the value of the 'make' property) values.

Support Me!
Buy Me A Coffee PayPal Me

Video Session:

Wrapping Up:

Hopefully, I think this article delivered some useful demo on consuming Azure Cosmo DB from the NestJS application. using I love to have your feedback, suggestions, and better techniques in the comment section below.

Follow Me:

Comments

Popular posts from this blog

.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

Blazor WebAssembly Custom Authentication From Scratch

In this article, we are going to explore and implement custom authentication from the scratch. In this sample, we will use JWT authentication for user authentication. Main Building Blocks Of Blazor WebAssembly Authentication: The core concepts of blazor webassembly authentication are: AuthenticationStateProvider Service AuthorizeView Component Task<AuthenticationState> Cascading Property CascadingAuthenticationState Component AuthorizeRouteView Component AuthenticationStateProvider Service - this provider holds the authentication information about the login user. The 'GetAuthenticationStateAsync()' method in the Authentication state provider returns user AuthenticationState. The 'NotifyAuthenticationStateChaged()' to notify the latest user information within the components which using this AuthenticationStateProvider. AuthorizeView Component - displays different content depending on the user authorization state. This component uses the AuthenticationStateProvider

How Response Caching Works In Asp.Net Core

What Is Response Caching?: Response Caching means storing of response output and using stored response until it's under it's the expiration time. Response Caching approach cuts down some requests to the server and also reduces some workload on the server. Response Caching Headers: Response Caching carried out by the few Http based headers information between client and server. Main Response Caching Headers are like below Cache-Control Pragma Vary Cache-Control Header: Cache-Control header is the main header type for the response caching. Cache-Control will be decorated with the following directives. public - this directive indicates any cache may store the response. private - this directive allows to store response with respect to a single user and can't be stored with shared cache stores. max-age - this directive represents a time to hold a response in the cache. no-cache - this directive represents no storing of response and always fetch the fr

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

Usage Of CancellationToken In Asp.Net Core Applications

When To Use CancellationToken?: In a web application request abortion or orphan, requests are quite common. On users disconnected by network interruption or navigating between multiple pages before proper response or closing of the browser, tabs make the request aborted or orphan. An orphan request can't deliver a response to the client, but it will execute all steps(like database calls, HTTP calls, etc) at the server. Complete execution of an orphan request at the server might not be a problem generally if at all requests need to work on time taking a job at the server in those cases might be nice to terminate the execution immediately. So CancellationToken can be used to terminate a request execution at the server immediately once the request is aborted or orphan. Here we are going to see some sample code snippets about implementing a CancellationToken for Entity FrameworkCore, Dapper ORM, and HttpClient calls in Asp.NetCore MVC application. Note: The sample codes I will show in

.Net5 Web API Managing Files Using Azure Blob Storage

In this article, we are going to understand the different file operations like uploading, reading, downloading, and deleting in .Net5 Web API application using Azure Blob Storage. Azure Blob Storage: Azure blob storage is Microsoft cloud storage. Blob storage can store a massive amount of file data as unstructured data. The unstructured data means not belong to any specific type, which means text or binary data. So something like images or pdf or videos to store in the cloud, then the most recommended is to use the blob store. The key component to creating azure blob storage resource: Storage Account:- A Storage account gives a unique namespace in Azure for all the data we will save. Every object that we store in Azure Storage has an address. The address is nothing but the unique name of our Storage Account name. The combination of the account name and the Azure Storage blob endpoint forms the base address for each object in our Storage account. For example, if our Storage Account is n

.Net5 Web API Redis Cache Using StackExchange.Redis.Extensions.AspNetCore Library

In this article, we are going to explore the integration of Redis cache in .Net5 Web API application using the 'StackExchange.Redis.Exntensions' library. Note:- Microsoft has introduced an 'IDistributedCache' interface in dotnet core which supports different cache stores like In-Memory, Redis, NCache, etc. It is simple and easy to work with  'IDistributedCache', for the Redis store with limited features but if we want more features of the Redis store we can choose to use 'StackExchange.Redis.Extensions'.  Click here for Redis Cache Integration Using IDistributedCache Interface . Overview On StackExchange.Redis.Extnesions Library: The 'StackExchange.Redis.Extension' library extended from the main library 'StackExchange.Redis'. Some of the key features of this library like: Default serialization and deserialization. Easy to save and fetch complex objects. Search key. Multiple Database Access Setup Redis Docker Instance: For this sampl

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

Endpoint Routing In Asp.Net Core

How Routing Works In  Core 2.1 And Below Versions?: In Asp.Net Core routing is configured using app.UseRouter() or app.UseMvc() middleware. app.UseMvc(routes => { routes.MapRoute( name: "default", template: "{controller=Home}/{action=Index}/{id?}"); }); Here in Dotnet Core version 2.1 or below versions on the execution of route middleware request will be navigated appropriate controller matched to the route. An operation or functionality which is dependent on route URL or route values and that need to be implemented before the execution of route middleware can be done by accessing the route path from the current request context as below app.Use(async (context, next) => { if(context.Request.Path.Value.IndexOf("oldvehicle") != -1) { context.Response.Redirect("vehicle"); } else { await next(); } }); app.UseMvc(routes => { routes.MapRoute( name: "vehicleRoute", template: "vehicle", defaul

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