## Three Ways to Access a Firebase Cloud Firestore Database

### Firebase Built-in Rest API

* **API Endpoint**

```
https://firestore.googleapis.com/v1/projects/YOUR_PROJECT_ID/databases/(default)/documents/YOUR_COLLECTION_NAME/
```

### Firebase Functions SDK

* **Node.js Environment**

```js
const functions = require("firebase-functions");
const admin = require("firebase-admin");

admin.initializeApp(functions.config().firebase);

const COLLECTION_NAME = functions.config().db.collection;

let db = admin.firestore();

let collection = db.collection(COLLECTION_NAME);

// Use doc, get, set, update and delete methods from collection.
```

### Third-Party ORM/ODM

* **Typesaurus ODM**

```js
const { collection, add, set, update, get, remove, all, query, where } = require('typesaurus');
const functions = require("firebase-functions");
const admin = require("firebase-admin");

admin.initializeApp(functions.config().firebase);

const COLLECTION_NAME = functions.config().db.collection;

// Model
type User = { name: string }
const users = collection<User>(COLLECTION_NAME)

// Add a document to a collection with auto-generated id
add(users, { name: 'Sasha' })
//=> Promise<Doc<User>>

// Set or overwrite a document with given id
set(users, '42', { name: 'Sasha' })
//=> Promise<Doc<User>>

// Update a document with given id
update(users, '42', { name: 'Sasha' })
//=> Promise<void>

// Get a document with given id
get(users, '42')
//=> Promise<Doc<User> | null>

// Get all documents in a collection
all(users)
//=> Promise<Doc<User>[]>

// Query collection
query(users, [where('name', '===', 'Sasha')])
//=> Promise<Doc<User>[]>

// Remove a document with given id
remove(users, '42')
//=> Promise<void>
```