4
5* `index.ts` - this is the **entrypoint** for this whole project
6* `database/` - this contains the code for interfacing with the app's SQLite database table
7
8## Hono
26## CRUD API Routes
27
28This app has two CRUD API routes: for reading and inserting into the messages table. They both speak JSON, which is standard. They import their functions from `/backend/database/queries.ts`. These routes are called from the React app to refresh and update data.
29
30## Errors
1# Database
2
3This app uses [Val Town SQLite](https://docs.val.town/std/sqlite/) to manage data. Every Val Town account comes with a free SQLite database, hosted on [Turso](https://turso.tech/). This folder is broken up into two files:
4
5* `migrations.ts` - code to set up the database tables the app needs
6* `queries.ts` - functions to run queries against those tables, which are imported and used in the main Hono server in `/backend/index.ts`
7
8## Migrations
9
10In `backend/database/migrations.ts`, this app creates a new SQLite table `reactHonoStarter_messages` to store messages.
11
12This "migration" runs once on every app startup because it's imported in `index.ts`. You can comment this line out for a slight (30ms) performance improvement on cold starts. It's left in so that users who fork this project will have the migration run correctly.
13
14SQLite has much more limited support for altering existing tables as compared to other databases. Often it's easier to create new tables with the schema you want, and then copy the data over. Happily LLMs are quite good at those sort of database operations, but please reach out in the [Val Town Discord](https://discord.com/invite/dHv45uN5RY) if you need help.
15
16## Queries
17
18The queries file is where running the migrations happen in this app. It'd also be reasonable for that to happen in index.ts, or as is said above, for that line to be commented out, and only run when actual changes are made to your database schema.
19
20The queries file exports functions to get and write data. It relies on shared types and data imported from the `/shared` directory.
374];
375
376// Insert memories into the database
377async function insertDemoMemories() {
378 try {
415 await insertDemoMemories();
416
417 console.log("Demo database successfully populated!");
418 return "Demo database successfully populated!";
419 } catch (error) {
420 console.error("Error populating demo database:", error);
421 throw error;
422 }
2
3/**
4 * Retrieves all memories from the database
5 * @param includeDate Whether to include date-specific memories or not
6 * @param startDate Optional start date to filter memories from (ISO format)
6import { Hono } from "npm:hono";
7import { type Memory } from "../shared/types.ts";
8import { createMemory, deleteMemory, getAllMemories, updateMemory } from "./database/queries.ts";
9
10const app = new Hono();
34
35/**
36 * Store a chat message in the database
37 */
38export async function storeChatMessage(
130 }
131
132 console.log(`Weather forecast updated in the database.`);
133 return summary;
134}
125 }
126
127 console.log(`Calendar events imported into the database.`);
128 return events;
129 } catch (error) {
8
9/**
10 * Retrieves previously generated fun facts from the memories database
11 * @returns Array of previous fun facts
12 */
47
48/**
49 * Inserts a fun fact into the memories database
50 * @param date Date for the fun fact in ISO format
51 * @param factText The fun fact text
208```
209โโโ backend/
210โ โโโ database/
211โ โ โโโ migrations.ts # Schema definitions
212โ โ โโโ queries.ts # DB query functions
270- Handle API calls properly with proper error catching
271
272### Database Patterns
273- Run migrations on startup or comment out for performance
274- Change table names when modifying schemas rather than altering