Mongoose

import mongoose, { Document, Schema, Model } from "mongoose";
 
// Define a schema representing an item in your domain.
const itemSchema = new Schema({
  id: String,
  name: String,
});
 
interface ItemDocument extends Document {
  id: string;
  name: string;
}
 
// Define an entity representing an item in your domain.
class Item {
  constructor(public id: string, public name: string) {}
}
 
// Define a repository interface for managing items.
interface ItemRepository {
  findById(id: string): Promise<Item | undefined>;
  save(item: Item): Promise<void>;
  remove(id: string): Promise<void>;
}
 
// Create a concrete implementation of the repository using Mongoose.
class MongooseItemRepository implements ItemRepository {
  private itemModel: Model<ItemDocument>;
 
  constructor() {
    this.itemModel = mongoose.model<ItemDocument>("Item", itemSchema);
  }
 
  async findById(id: string): Promise<Item | undefined> {
    const item = await this.itemModel.findOne({ id }).exec();
    return item ? new Item(item.id, item.name) : undefined;
  }
 
  async save(item: Item): Promise<void> {
    await this.itemModel
      .updateOne({ id: item.id }, { name: item.name }, { upsert: true })
      .exec();
  }
 
  async remove(id: string): Promise<void> {
    await this.itemModel.deleteOne({ id }).exec();
  }
}
 
// Usage
mongoose.connect("mongodb://localhost:27017/your-database-name", {
  useNewUrlParser: true,
  useUnifiedTopology: true,
});
 
const itemRepository: ItemRepository = new MongooseItemRepository(mongoose);
 
const item1 = new Item("1", "Item 1");
const item2 = new Item("2", "Item 2");
 
// Save items to the repository
itemRepository.save(item1);
itemRepository.save(item2);
 
// Retrieve an item from the repository
const retrievedItem = await itemRepository.findById("1");
console.log(retrievedItem);
 
// Remove an item from the repository
await itemRepository.remove("2");
 
// Verify the item is removed
const removedItem = await itemRepository.findById("2");
console.log(removedItem); // This should be undefined