MongoDB with the Rust driver

Uses the mongodb crate 3.9. The code is an ordinary application for the original database; nothing in it knows about MachNoSQL.

The only change

mongodb://app:secret@mongo.example.com:27017/shop?authSource=admin
mongodb://app:secret@machnosql.example.com:27017/shop?authSource=admin

The address comes from the environment variable MONGODB_URI, so switching to MachNoSQL changes configuration only.

Run

export MONGODB_URI='mongodb://app:secret@machnosql.example.com:27017/shop?authSource=admin'
cargo run

Source

The program as it is kept and tested in the Mach Database NoSQL repository; highlighted lines read the connection setting.

src/main.rs

//! Orders example for MongoDB, unchanged on MachNoSQL.

use futures::TryStreamExt;
use mongodb::bson::{Document, doc};
use mongodb::Client;

#[tokio::main]
async fn main() -> mongodb::error::Result<()> {
    let uri = std::env::var("MONGODB_URI").expect("set MONGODB_URI");
    let client = Client::with_uri_str(uri).await?;
    let orders = client.database("shop").collection::<Document>("orders");

    orders.delete_many(doc! {}).await?;
    orders
        .insert_many([
            doc! { "customer": "ada", "item": "keyboard", "qty": 1, "price": 49.0 },
            doc! { "customer": "ada", "item": "mouse", "qty": 2, "price": 19.5 },
            doc! { "customer": "linus", "item": "monitor", "qty": 1, "price": 199.0 },
        ])
        .await?;

    println!("{:?}", orders.find_one(doc! { "item": "mouse" }).await?);
    orders
        .update_one(doc! { "item": "mouse" }, doc! { "$inc": { "qty": 1 } })
        .await?;

    let pipeline = [
        doc! { "$group": { "_id": "$customer", "revenue": { "$sum": { "$multiply": ["$qty", "$price"] } } } },
        doc! { "$sort": { "revenue": -1 } },
    ];
    let mut rows = orders.aggregate(pipeline).await?;
    while let Some(row) = rows.try_next().await? {
        println!("{row}");
    }
    Ok(())
}

Cargo.toml

[package]
name = "machnosql-example-mongodb"
version = "0.1.0"
edition = "2024"
publish = false

[dependencies]
futures = "0.3.34"
mongodb = "3.9.1"
tokio = { version = "1.54.1", features = ["macros", "rt-multi-thread"] }