Description

Azure Database (Table Storage, Cosmos DB and more) module for Nest framework (node.js)

Tutorial

Learn how to get started with Azure table storage for NestJS

Before Installation

For Table Storage

1. Create a Storage account and resource (read more)
2. For Table Storage, In the Azure Portal, go to Dashboard > Storage > your-storage-account.
3. Note down the "Storage account name" and "Connection string" obtained at Access keys under Settings tab.

For Cosmos DB

1. Create a Cosmos DB account and resource (read more)
2. For Cosmos DB, In the Azure Portal, go to Dashboard > Azure Cosmos DB > your-cosmos-db-account.
3. Note down the "URI" and "Primary Key" obtained at Keys under Settings tab.

Installation

$ npm i --save @nestjs/azure-database

Usage

For Azure Table Storage support

1. Create or update your existing .env file with the following content:

AZURE_STORAGE_CONNECTION_STRING=

2. IMPORTANT: Make sure to add your .env file to your .gitignore! The .env file MUST NOT be versioned on Git.

3. Make sure to include the following call to your main file:

if (process.env.NODE_ENV !== 'production') require('dotenv').config();

This line must be added before any other imports!

Example

Prepare your entity

0. Create a new feature module, eg. with the nest CLI:

$ nest generate module contact

1. Create a Data Transfer Object (DTO) inside a file named contact.dto.ts:

export class ContactDTO {
  name: string;
  message: string;
}

2. Create a file called contact.entity.ts and describe the entity model using the provided decorators:

• @EntityPartitionKey(value: string): Represents the PartitionKey of the entity (required).

• @EntityRowKey(value: string): Represents the RowKey of the entity (required).

• @EntityInt32(value?: string): For signed 32-bit integer values.

• @EntityInt64(value?: string): For signed 64-bit integer values.

• @EntityBinary(value?: string): For binary (blob) data.

• @EntityBoolean(value?: string): For true or false values.

• @EntityString(value?: string): For character data.

• @EntityDouble(value?: string): For floating point numbers with 15 digit precision.

• @EntityDateTime(value?: string): For time of day.

For instance, the shape of the following entity:

import { EntityPartitionKey, EntityRowKey, EntityString } from '@nestjs/azure-database';

@EntityPartitionKey('ContactID')
@EntityRowKey('ContactName')
export class Contact {
  @EntityString() name: string;
  @EntityString() message: string;
}

Will be automatically converted to:

{
  "PartitionKey": { "_": "ContactID", "$": "Edm.String" },
  "RowKey": { "_": "ContactName", "$": "Edm.String" },
  "name": { "_": undefined, "$": "Edm.String" },
  "message": { "_": undefined, "$": "Edm.String" }
}

Note: The provided entity type annotations represent the Entity Data Model types.

3. Import the AzureTableStorageModule inside your Nest feature module contact.module.ts:

import { Module } from '@nestjs/common';
import { AzureTableStorageModule } from '@nestjs/azure-database';
import { ContactController } from './contact.controller';
import { ContactService } from './contact.service';
import { Contact } from './contact.entity';

@Module({
  imports: [AzureTableStorageModule.forFeature(Contact)],
  providers: [ContactService],
  controllers: [ContactController],
})
export class ContactModule {}

You can optionally pass in the following arguments:

AzureTableStorageModule.forFeature(Contact, {
  table: 'AnotherTableName',
  createTableIfNotExists: true,
});

• table: string: The name of the table. If not provided, the name of the Contact entity will be used as a table name
• createTableIfNotExists: boolean: Whether to automatically create the table if it doesn't exists or not:
  • If true the table will be created during the startup of the app.
  • If false the table will not be created. You will have to create the table by yourself before querying it!

CRUD operations

0. Create a service that will abstract the CRUD operations:

$ nest generate service contact

1. Use the @InjectRepository(Contact) to get an instance of the Azure Repository for the entity definition created earlier:

import { Injectable } from '@nestjs/common';
import { Repository, InjectRepository } from '@nestjs/azure-database';
import { Contact } from './contact.entity';

@Injectable()
export class ContactService {
  constructor(
    @InjectRepository(Contact)
    private readonly contactRepository: Repository<Contact>,
  ) {}
}

The AzureTableStorageRepository provides a couple of public APIs and Interfaces for managing various CRUD operations:

CREATE

create(entity: T, rowKeyValue?: string): Promise<T>: creates a new entity.

  @Post()
  async create(contact: Contact, rowKeyValue: string): Promise<Contact> {
    //if rowKeyValue is null, rowKeyValue will generate a UUID
    return this.contactRepository.create(contact, rowKeyValue)
  }

READ

find(rowKey: string, entity: Partial<T>): Promise<T>: finds one entity using its RowKey.

  @Get(':rowKey')
  async getContact(@Param('rowKey') rowKey) {
    try {
      return await this.contactRepository.find(rowKey, new Contact());
    } catch (error) {
      // Entity not found
      throw new UnprocessableEntityException(error);
    }
  }

findAll(tableQuery?: azure.TableQuery, currentToken?: azure.TableService.TableContinuationToken): Promise<AzureTableStorageResultList<T>>: finds all entities that match the given query (return all entities if no query provided).

  @Get()
  async getAllContacts() {
    return await this.contactRepository.findAll();
  }

UPDATE

update(rowKey: string, entity: Partial<T>): Promise<T>: Updates an entity. It does a partial update.

  @Put(':rowKey')
  async saveContact(@Param('rowKey') rowKey, @Body() contactData: ContactDTO) {
    try {
      const contactEntity = new Contact();
      // Disclaimer: Assign only the properties you are expecting!
      Object.assign(contactEntity, contactData);

      return await this.contactRepository.update(rowKey, contactEntity);
    } catch (error) {
      throw new UnprocessableEntityException(error);
    }
  }
  @Patch(':rowKey')
  async updateContactDetails(@Param('rowKey') rowKey, @Body() contactData: Partial<ContactDTO>) {
    try {
      const contactEntity = new Contact();
      // Disclaimer: Assign only the properties you are expecting!
      Object.assign(contactEntity, contactData);

      return await this.contactRepository.update(rowKey, contactEntity);
    } catch (error) {
      throw new UnprocessableEntityException(error);
    }
  }

DELETE

delete(rowKey: string, entity: T): Promise<AzureTableStorageResponse>: Removes an entity from the database.

  @Delete(':rowKey')
  async deleteDelete(@Param('rowKey') rowKey) {
    try {
      const response = await this.contactRepository.delete(rowKey, new Contact());

      if (response.statusCode === 204) {
        return null;
      } else {
        throw new UnprocessableEntityException(response);
      }
    } catch (error) {
      throw new UnprocessableEntityException(error);
    }
  }

For Azure Cosmos DB support

1. Create or update your existing .env file with the following content:

AZURE_COSMOS_DB_NAME=
AZURE_COSMOS_DB_ENDPOINT=
AZURE_COSMOS_DB_KEY=

2. IMPORTANT: Make sure to add your .env file to your .gitignore! The .env file MUST NOT be versioned on Git.

3. Make sure to include the following call to your main file:

if (process.env.NODE_ENV !== 'production') require('dotenv').config();

This line must be added before any other imports!

Example

Note: Check out the CosmosDB example project included in the sample folder

Prepare your entity

0. Create a new feature module, eg. with the nest CLI:

$ nest generate module event

1. Create a Data Transfer Object (DTO) inside a file named event.dto.ts:

export class EventDTO {
  name: string;
  type: string;
  date: Date;
  location: Point;
}

2. Create a file called event.entity.ts and describe the entity model using the provided decorators:

• @CosmosPartitionKey(value: string): Represents the PartitionKey of the entity (required).

• @CosmosDateTime(value?: string): For DateTime values.

For instance, the shape of the following entity:

import { CosmosPartitionKey, CosmosDateTime, Point } from '@nestjs/azure-database';

@CosmosPartitionKey('type')
export class Event {
  id?: string;
  type: string;
  @CosmosDateTime() createdAt: Date;
  location: Point;
}

Will be automatically converted to:

{
  "type": "Meetup",
  "createdAt": "2019-11-15T17:05:25.427Z",
  "position": {
    "type": "Point",
    "coordinates": [2.3522, 48.8566]
  }
}

3. Import the AzureCosmosDbModule inside your Nest feature module event.module.ts:

import { Module } from '@nestjs/common';
import { AzureCosmosDbModule } from '@nestjs/azure-database';
import { EventController } from './event.controller';
import { EventService } from './event.service';
import { Event } from './event.entity';

@Module({
  imports: [
    AzureCosmosDbModule.forRoot({
      dbName: process.env.AZURE_COSMOS_DB_NAME,
      endpoint: process.env.AZURE_COSMOS_DB_ENDPOINT,
      key: process.env.AZURE_COSMOS_DB_KEY,
    }),
    AzureCosmosDbModule.forFeature([{ dto: Event }]),
  ],
  providers: [EventService],
  controllers: [EventController],
})
export class EventModule {}

CRUD operations

0. Create a service that will abstract the CRUD operations:

$ nest generate service event

1. Use the @InjectModel(Event) to get an instance of the Azure Cosmos DB Container for the entity definition created earlier:

import { Injectable } from '@nestjs/common';
import { InjectModel } from '@nestjs/azure-database';
import { Event } from './event.entity';

@Injectable()
export class EventService {
  constructor(
    @InjectModel(Event)
    private readonly eventContainer,
  ) {}
}

The Azure Cosmos DB Container provides a couple of public APIs and Interfaces for managing various CRUD operations:

CREATE

create(entity: T): Promise<T>: creates a new entity.

  @Post()
  async create(event: Event): Promise<Event> {
      return this.eventContainer.items.create(event)
  }

READ

query<T>(query: string | SqlQuerySpec, options?: FeedOptions): QueryIterator<T>: run a SQL Query to find a document.

  @Get(':id')
  async getContact(@Param('id') id) {
    try {
       const querySpec = {
           query: "SELECT * FROM root r WHERE r.id=@id",
           parameters: [
             {
               name: "@id",
               value: id
             }
           ]
         };
        const { resources } = await this.eventContainer.items.query<Event>(querySpec).fetchAll()
         return resources
    } catch (error) {
      // Entity not found
      throw new UnprocessableEntityException(error);
    }
  }

UPDATE

read<T>(options?: RequestOptions): Promise<ItemResponse<T>>: Get a document. replace<T>(body: T, options?: RequestOptions): Promise<ItemResponse<T>>: Updates a document.

  @Put(':id')
  async saveEvent(@Param('id') id, @Body() eventData: EventDTO) {
    try {
      const { resource: item } = await this.eventContainer.item<Event>(id, 'type').read()

      // Disclaimer: Assign only the properties you are expecting!
      Object.assign(item, eventData);

      const { resource: replaced } = await this.eventContainer
       .item(id, 'type')
       .replace<Event>(item)
      return replaced
    } catch (error) {
      throw new UnprocessableEntityException(error);
    }
  }

DELETE

delete<T>(options?: RequestOptions): Promise<ItemResponse<T>>: Removes an entity from the database.

  @Delete(':id')
  async deleteEvent(@Param('id') id) {
    try {
      const { resource: deleted } = await this.eventContainer
       .item(id, 'type')
       .delete<Event>()

      return deleted;
    } catch (error) {
      throw new UnprocessableEntityException(error);
    }
  }

Support

Nest is an MIT-licensed open source project. It can grow thanks to the sponsors and support by the amazing backers. If you'd like to join them, please read more here.

Stay in touch

• Author - Wassim Chegham
• Website - https://wassim.dev
• Twitter - @manekinekko

License

Nest is MIT licensed.