backend/docs/typescript-frontend-integration.md

TypeScript Frontend Integration Guide

This document explains how frontend developers should integrate with the backend through the reusable TypeScript client at libs/geo-api-client.

Primary backend URL for integration:

• https://momswap.produktor.duckdns.org/

Goals

• Keep cryptographic signing logic in one place.
• Avoid duplicating API request code in frontend apps.
• Use a consistent local key storage format across projects.

Client package location

• Source: libs/geo-api-client/src
• Entry point: libs/geo-api-client/src/index.ts
• Build output (browser ESM): libs/geo-api-client/dist/index.js

Build and test the client

cd libs/geo-api-client
bun install
bun test
bun run build

Public API (current)

Class: GeoApiClient

Constructor:

• new GeoApiClient(baseUrl, storage, storageKey?)

Key methods:

• ensureKeysInStorage()
• getStoredKeys()
• importKeys(keys)
• exportKeys()
• setAccessToken(token)
• createChallenge(publicKey)
• loginWithSignature(publicKey, privateKey)
• createInvitation(payload, inviterPrivateKey)
• registerWithInvitation(...)
• listCollections()
• createCollection(name)
• listFeatures(collectionId)
• createPointFeature(collectionId, lon, lat, properties)

Recommended integration flow

1. Create one GeoApiClient instance per backend base URL.
2. Call ensureKeysInStorage() when app initializes.
3. Use loginWithSignature() to obtain and set a bearer token.
4. Call collection/feature methods after authentication.
5. Use importKeys/exportKeys in profile settings UX.

Example (TypeScript app)

import { GeoApiClient } from "../libs/geo-api-client/dist/index.js";

const storage = window.localStorage;

const storageLike = {
  getItem: (key: string) => storage.getItem(key),
  setItem: (key: string, value: string) => storage.setItem(key, value),
  removeItem: (key: string) => storage.removeItem(key),
};

const client = new GeoApiClient("https://momswap.produktor.duckdns.org", storageLike);

const keys = await client.ensureKeysInStorage();
await client.loginWithSignature(keys.publicKey, keys.privateKey);

const created = await client.createCollection("My Places");
await client.createPointFeature(created.id, -16.6291, 28.4636, { name: "Santa Cruz" });
const features = await client.listFeatures(created.id);
console.log(features);

Security notes

• Private keys are currently stored in browser storage via the selected storage adapter.
• If your frontend has stronger security requirements, wrap the storage adapter with your own encryption/decryption layer before calling setItem/getItem.
• Never send private keys to the backend.

No-build frontend compatibility

For no-bundler apps, import the built ESM file:

<script type="module">
  import { GeoApiClient } from "../libs/geo-api-client/dist/index.js";
  // use client...
</script>

The backend itself serves static UI at /web/, but this library can be consumed by any frontend runtime that supports fetch, TextEncoder, and ES modules.

For local development you can switch the client base URL to http://localhost:8122.