MongoDB Cheatsheet 06 — Drivers (Python, Node)

from pymongo import MongoClient

client = MongoClient("mongodb://localhost:27017")
db = client.myapp
users = db.users

users.insert_one({"name": "Alice"})
list(users.find({"age": {"$gt": 25}}))
users.update_one({"name": "Alice"}, {"$set": {"age": 31}})
users.delete_one({"_id": ...})

users.create_index([("email", 1)], unique=True)

client.close()

from motor.motor_asyncio import AsyncIOMotorClient

client = AsyncIOMotorClient("mongodb://localhost:27017")
db = client.myapp

await db.users.insert_one({"name": "Alice"})
async for u in db.users.find({"active": True}):
    print(u)

await client.close()

client = MongoClient(uri, maxPoolSize=100, minPoolSize=10)

from pymongo import InsertOne, UpdateOne, DeleteOne

users.bulk_write([
    InsertOne({"name": "A"}),
    UpdateOne({"name": "B"}, {"$set": {"age": 30}}),
    DeleteOne({"_id": ...}),
], ordered=False)

list(db.orders.aggregate([
    {"$match": {"status": "completed"}},
    {"$group": {"_id": "$user_id", "total": {"$sum": "$amount"}}},
]))

with client.start_session() as s:
    with s.start_transaction():
        db.accounts.update_one({"_id": a}, {"$inc": {"bal": -100}}, session=s)
        db.accounts.update_one({"_id": b}, {"$inc": {"bal": 100}}, session=s)

from pydantic import BaseModel, Field
from bson import ObjectId

class User(BaseModel):
    id: ObjectId = Field(alias="_id")
    name: str
    email: str
    
    class Config:
        arbitrary_types_allowed = True
        json_encoders = {ObjectId: str}

doc = users.find_one({...})
user = User.model_validate(doc)

from beanie import Document, init_beanie

class User(Document):
    name: str
    email: str
    
    class Settings:
        name = "users"

await init_beanie(database=db, document_models=[User])

await User(name="Alice", email="[email protected]").insert()
user = await User.find_one(User.email == "[email protected]")

import { MongoClient, ObjectId } from "mongodb";

const client = new MongoClient("mongodb://localhost:27017");
await client.connect();
const db = client.db("myapp");
const users = db.collection("users");

await users.insertOne({ name: "Alice" });
const u = await users.findOne({ _id: new ObjectId("...") });
await users.updateOne({ _id }, { $set: { age: 31 } });

await client.close();

npm i mongoose

import mongoose from "mongoose";

await mongoose.connect("mongodb://localhost:27017/myapp");

const UserSchema = new mongoose.Schema({
    name: { type: String, required: true },
    email: { type: String, unique: true },
    age: Number,
}, { timestamps: true });

const User = mongoose.model("User", UserSchema);

await User.create({ name: "Alice", email: "[email protected]" });
const user = await User.findOne({ email: "[email protected]" });
await User.updateOne({ _id }, { age: 31 });

UserSchema.index({ email: 1 }, { unique: true });
UserSchema.index({ name: "text" });

UserSchema.pre("save", function (next) {
    this.updated = new Date();
    next();
});

UserSchema.post("save", function (doc) {
    notify(doc);
});

const PostSchema = new Schema({
    title: String,
    author: { type: Schema.Types.ObjectId, ref: "User" },
});

const post = await Post.findById(id).populate("author");

const cursor = users.find({});
for await (const u of cursor) {
    console.log(u);
}

interface User { _id: ObjectId; name: string; email: string; }

const users = db.collection<User>("users");
await users.insertOne({ name: "A", email: "a@b" });   // typed