@tjomson/duckdb-async

duckdb-async

TypeScript wrappers using Promises for the duckdb Node.JS API

Overview and Basic Usage

This repository provides an API that wraps the DuckDb NodeJS API using Promises instead of callbacks. The library is implemented in TypeScript to provide static type checking for TypeScript developers. It includes the existing duckdb NPM module as a dependency, so it should be possible to write applications in TypeScript using only duckdb-async as a direct dependency.

Basic usage is straightforward. For example:

import { Database } from "duckdb-async";

async function simpleTest() {
  const db = await Database.create(":memory:");
  const rows = await db.all("select * from range(1,10)");
  console.log(rows);
}

simpleTest();

Note that the static method Database.create(...) is used in place of new Database(...) in the DuckDb NodeJS API because the underlying NodeJS API uses a callback in the constructor, and it's not possible to have constructors return promises.

The API should be relatively complete -- there are wrappers for all of the Connection, Database and Statement classes from the underlying NodeJS API, with methods that return promises instead of taking callbacks. A notable exception is the each methods on these classes. The each method invokes a callback multiple times, once for each row of the result set. Since promises can only be resolved once, it doesn't make sense to convert this method to a promise-based API, so the each method still provides the same callback-based interface as the original Node.JS API.