SQLx-D1 realizes "SQLx for Cloudflare D1" with compile-time SQL verification in Rust Cloudflare development !

worker version: 0.6

Background

Miniflare's local D1 emulator is, essentially, just a .sqlite file.

This fact has been brought a lot of Rustaceans trying sqlx with sqlite feature for D1, but it's impossible because:

• sqlx-sqlite contains a native dependency of SQLite driver.
• actual D1 itself doesn't expose raw database interface.

SQLx-D1 works around them by loading sqlx-sqlite only in macro context and just providing a conversion layer between D1 and SQLx in library context.

Features

• SQLx interface for Cloudflare D1
• Batteries included, sqlx is not needed in dependencies
• Compile-time SQL verification
  • by miniflare's local D1 emulator ( internally using sqlx-sqlite )
  • by query caches in .sqlx directory ( offline mode; cargo sqlx prepare )
• No environment variable or .env file is needed
  • D1 emulator's location is fixed to .wrangler/state/v3/d1/miniflare-D1DatabaseObject
  • falling back to offline mode when it doesn't exist and .sqlx directory exists

Unsupported features

• Transaction
  • Let's wait for Cloudflare's side to support transation on D1 !
• Connection pool ( sqlx::Pool internally requires Rust async runtime (tokio / asycn-std) and time implemetation of WASM runtime which is not done on Cloudflare Workers )
  • alternatively, &sqlx_d1::D1Connection implements Executor, not only &mut one.
• derive Type, Encode, Decode
  • maybe added if requested
  • workaround if needed: add sqlx to dependencies and use its ones

Example

# Cargo.toml

[dependencies]
sqlx-d1 = { version = "0.2", features = ["macros"] }
worker = { version = "0.6", features = ["d1"] }
serde = { version = "1.0", features = ["derive"] }

wrangler d1 create <DATABASE_NAME> # prints <DATABASE_ID>

# wrangler.toml

[[d1_databases]]
binding = "DB"
database_name = "<DATABASE_NAME>"
database_id = "<DATABASE_ID>"

wrangler d1 migrations create DB 'schema'

-- migrations/0001_schema.sql

CREATE TABLE users (
    id   INTEGER NOT NULL PRIMARY KEY,
    name TEXT NOT NULL,
    age  INTEGER
);

wrangler d1 migrations apply DB --local

// src/lib.rs

#[worker::event(fetch)]
async fn main(
    mut req: worker::Request,
    env: worker::Env,
    _ctx: worker::Context,
) -> worker::Result<worker::Response> {
    let d1 = env.d1("DB")?;
    let conn = sqlx_d1::D1Connection::new(d1);

    #[derive(serde::Deserialize)]
    struct CreateUser {
        name: String,
        age: Option<u8>,
    }

    let req = req.json::<CreateUser>().await?;

    let id = sqlx_d1::query!(
        "
        INSERT INTO users (name, age) VALUES (?, ?)
        RETURNING id
        ",
            req.name,
            req.age
        )
        .fetch_one(&conn)
        .await
        .map_err(|e| worker::Error::RustError(e.to_string()))?
        .id;

    worker::Response::ok(format!("Your id is {id}!"))
}

License

SQLx-D1 is licensed under MIT LICENSE ( LICENSE or https://opensource.org/licenses/MIT ) .