Health Dashboard API

[diamondburned]

This issue proposes an API that allows querying health information for Diamond or 0xd14.

Architecture

---
title: Architecture Diagram
---

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flowchart LR
  subgraph Server["Backend Server"]
    api("API Backend")
    vic("VictoriaMetrics")
    caddy("Caddy")
  end

  subgraph Desktop["Desktop"]
    db("GadgetBridge DB")
    subgraph Telegraf
      in("GadgetBridge Input")
    end
  end

  subgraph S3["Phone"]
    gg("GadgetBridge")
    fs("FolderSync")
  end

  fossil["Smartwatch"]
  fossil --> gg

  gg --- fs
  fs --> db
  db --> in
  in --> vic
  api --- vic
  api --> caddy
  caddy --> Public["Public View"]

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Database Ingestor

Currently, Diamond wears a Fossil hybrid smartwatch paired to its phone using Gadgetbridge, which automatically exports a SQLite database hourly into a folder that is then synced via FolderSync to its desktop. A service (named Database Ingestor) should be created to export data from this database to an external database server.

This service should do ensure that the VictoriaMetrics database is up to date with the local SQLite database. Note that VictoriaMetrics loads its data using the InfluxDB API.

The backend can then simply consume the VictoriaMetrics database and render a JSON containing the health data that is useful for client consumption.

Backend Server

This proposal indirectly proposes a new microservice-architecture backend for serving the API. Its code shall live in /backend.

Backend Endpoint

The backend's base endpoint is https://libdb.so/api/. Components become part of the backend API with the URL https://libdb.so/api/<component>[/<version>]. Note that the version path is optional but is strongly recommended.

API Specs

The API specification must eventually be declared using OpenAPI.

• /api/health/v1 - the base endpoint
  • GET /api/health/v1/latest.json - the latest health data in JSON, schema yet to be defined
• /api/_all.json - pseudo-endpoint that fetches all data locally then returns it to avoid roundtrip time
  • GET /api/_all.json - the above data.

Action Items

• Initialize backend boilerplate code and build outputs
• Write up OpenAPI schema for API
• Set up backend infrastructure on server
• Set up VictoriaMetrics infrastructure on server
• Implement database ingestor service
• Deploy database ingestor service on desktop
• Publish OpenAPI documentation at /api/docs.