QAIL PostgreSQL Driver

Native PostgreSQL wire protocol driver for QAIL.

Architecture

This crate implements two layers:

Layer 2: Protocol (Pure, Sync)

• protocol::PgEncoder - Compiles QailCmd to wire protocol bytes
• No async, no I/O, no tokio
• Input: AST → Output: BytesMut

Layer 3: Driver (Async I/O)

• driver::PgConnection - TCP networking
• Uses tokio for async I/O
• Sends bytes from Layer 2, receives responses

Example

use qail_core::ast::QailCmd;
use qail_pg::protocol::PgEncoder;

// Layer 2: Pure computation (no async needed)
let cmd = QailCmd::get("users");
let bytes = PgEncoder::encode_simple_query(&cmd);

// Layer 3: Async I/O (uses tokio)
let mut driver = PgDriver::connect("localhost", 5432, "user", "db").await?;
let rows = driver.fetch_all(&cmd).await?;