Connecting Hono to D1

We have our database and our schema. Now let’s write the API endpoints to use them!

Setup

First, we need to initialize Drizzle inside our Hono app. We do this using the DB binding we configured in wrangler.json.

import { Hono } from "hono";
import { drizzle } from "drizzle-orm/d1";
import { task } from "./db/schema"; // Import your table definition
import { eq } from "drizzle-orm";

// Define the environment type so TypeScript knows about DB
type Env = {
  Bindings: {
    DB: D1Database;
  };
};

const app = new Hono<Env>();

Reading Data (SELECT)

To fetch all tasks:

app.get("/tasks", async (c) => {
  const db = drizzle(c.env.DB);

  // SELECT * FROM task
  const result = await db.select().from(task);

  return c.json(result);
});

Filtering

To fetch a specific task by ID:

app.get("/tasks/:id", async (c) => {
  const id = c.req.param("id");
  const db = drizzle(c.env.DB);

  // SELECT * FROM task WHERE id = ?
  const result = await db.select().from(task).where(eq(task.id, id));

  return c.json(result[0]); // Drizzle returns an array
});

Writing Data (INSERT)

To create a new task:

app.post("/tasks", async (c) => {
  const body = await c.req.json();
  const db = drizzle(c.env.DB);

  const newTask = {
    id: crypto.randomUUID(),
    title: body.title,
    status: "todo",
    userId: "user_123", // Hardcoded for now
    createdAt: new Date(),
    updatedAt: new Date(),
  };

  // INSERT INTO task VALUES (...)
  await db.insert(task).values(newTask);

  return c.json(newTask, 201);
});

Updating Data (UPDATE)

To mark a task as completed:

app.patch("/tasks/:id", async (c) => {
  const id = c.req.param("id");
  const db = drizzle(c.env.DB);

  // UPDATE task SET status = 'completed' WHERE id = ?
  await db.update(task).set({ status: "completed" }).where(eq(task.id, id));

  return c.json({ message: "Updated" });
});

Deleting Data (DELETE)

To remove a task:

app.delete("/tasks/:id", async (c) => {
  const id = c.req.param("id");
  const db = drizzle(c.env.DB);

  // DELETE FROM task WHERE id = ?
  await db.delete(task).where(eq(task.id, id));

  return c.json({ message: "Deleted" });
});

Now you have the power to build a full CRUD (Create, Read, Update, Delete) API backed by a real database!