cosmos.ts

import { Collection, Db, Filter, FindCursor, MongoClient, UpdateFilter, UpdateOptions, UpdateResult, WithId } from 'mongodb';

import { Emit, Product } from './types'

export class DataClient {

    async start(emit: Emit) {
        const client: MongoClient = await this.createClient(emit);

        emit('Current Status:\tStarting...');

        const container: Collection<Product> = await this.createCollection(emit, client);

        await this.createDocumentVerbose(emit, container);

        await this.createDocumentConcise(emit, container);

        await this.readDocument(emit, container);

        await this.queryDocuments(emit, container);

        emit('Current Status:\tFinalizing...');
    }

    async createClient(emit: Emit): Promise<MongoClient> {
const client = new MongoClient(
    "<azure-cosmos-db-mongodb-connection-string>"
);

        var host = client.options.hosts[0];
        if (host) {
            console.log(`ENDPOINT:\t${host.host}:${host.port}`);
        }

        return client;
    }

    async createCollection(emit: Emit, client: MongoClient): Promise<Collection<Product>> {
        const databaseName: string = process.env.CONFIGURATION__AZURECOSMOSDB__DATABASENAME ?? 'cosmicworks';
        const database: Db = client.db(databaseName);

        emit(`Get database:\t${database.databaseName}`);

        const collectionName: string = process.env.CONFIGURATION__AZURECOSMOSDB__COLLECTIONNAME ?? 'products';
        const collection: Collection<Product> = database.collection<Product>(collectionName);

        emit(`Get collection:\t${collection.collectionName}`);

        return collection;
    }

    async createDocumentVerbose(emit: Emit, collection: Collection<Product>) {
        var document: Product = {
            _id: 'aaaaaaaa-0000-1111-2222-bbbbbbbbbbbb',
            category: 'gear-surf-surfboards',
            name: 'Yamba Surfboard',
            quantity: 12,
            price: 850.00,
            clearance: false
        };
        
        var query: Filter<Product> = {
            _id: 'aaaaaaaa-0000-1111-2222-bbbbbbbbbbbb',
            category: 'gear-surf-surfboards'
        };
        var payload: UpdateFilter<Product> = {
            $set: document
        };
        var options: UpdateOptions = {
            upsert: true
        };
        var response: UpdateResult<Product> = await collection.updateOne(query, payload, options);

        if (response.acknowledged) {
            emit(`Upserted document:\t${JSON.stringify(document)}`);
        }
    }

    async createDocumentConcise(emit: Emit, collection: Collection<Product>) {
        var document: Product = {
            _id: 'bbbbbbbb-1111-2222-3333-cccccccccccc',
            category: 'gear-surf-surfboards',
            name: 'Kiama Classic Surfboard',
            quantity: 25,
            price: 790.00,
            clearance: true
        };
        
        var query: Filter<Product> = { 
            _id: 'bbbbbbbb-1111-2222-3333-cccccccccccc', 
            category: 'gear-surf-surfboards' 
        };
        var payload: UpdateFilter<Product> = {
            $set: document
        };
        var options: UpdateOptions = { 
            upsert: true 
        };
        var response: UpdateResult<Product> = await collection.updateOne(query, payload, options);

        if (response.acknowledged) {
            emit(`Upserted document:\t${JSON.stringify(document)}`);
        }
    }

    async readDocument(emit: Emit, collection: Collection<Product>) {
        var query: Filter<Product> = { 
            _id: 'aaaaaaaa-0000-1111-2222-bbbbbbbbbbbb', 
            category: 'gear-surf-surfboards' 
        };

        var response: WithId<Product> | null = await collection.findOne(query);
        var read_item: Product = response as Product;

        emit(`Read document _id:\t${read_item._id}`);
        emit(`Read document:\t${JSON.stringify(read_item)}`);
    }

    async queryDocuments(emit: Emit, collection: Collection<Product>) {
        var query: Filter<Product> = { 
            category: 'gear-surf-surfboards' 
        };

        var response: FindCursor<WithId<Product>> = await collection.find(query);

        for await (const item of response) {
            emit(`Found document:\t${item.name}\t${item._id}`);
        }
    }
}