Tips for converting Promise<Document[]> in JavaScript / TypeScript?

Question

Tips for converting Promise<Document[]> in JavaScript / TypeScript?

After executing a lengthy MongoDB query, I have obtained the result:

const data = collection.find({}).project({ name: 1 }).toArray()

The type of this result is Promise<Document[]>

I attempted to perform a transformation on it, but encountered difficulties:

let transformedData = data.map((item) => {item._id, { name: item.name }})

In Vapor / Swift, there exists a map function for promises as well. Is there a similar functionality in JS / TS?

Is there a way to apply additional operations on the Promise<Document[]>?

javascript typescript promise

Answer 1

Answer №1

To handle Promises effectively, it is important to utilize .then for functionality and .catch for handling errors.

Consider the following example:

const promise = new Promise((resolve, reject) => {
setTimeout(() =>{
console.log(reject)
},1000)
})
promise.then((result) => console.log(result)).catch((error) => console.log(error));

Additionally, make sure to include return when using functions like map and enclosing them in {} brackets to prevent potential errors.

Answer 2

To handle Promises effectively, it is important to utilize .then for functionality and .catch for handling errors.

Consider the following example:

const promise = new Promise((resolve, reject) => {
setTimeout(() =>{
console.log(reject)
},1000)
})
promise.then((result) => console.log(result)).catch((error) => console.log(error));

Additionally, make sure to include return when using functions like map and enclosing them in {} brackets to prevent potential errors.

Answer 3

Answer №2

The .then() method can be utilized in various sections of your code

Answer 4

The .then() method can be utilized in various sections of your code

Tips for converting Promise<Document[]> in JavaScript / TypeScript?

Answer №1

Answer №2

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