Files
btcprice/README.md
T
magnusandClaude Opus 5 864674bd09 Point citadel btcprice at the local btcdata over btc-network
omarchy is gone, but the citadel deployment still set
BTCDATA_URL=http://192.168.50.42:4102 and ran standalone on its own
compose network. Every request that proxies to btcdata failed with
httpx.ConnectError: All connection attempts failed.

btcdata now runs on citadel too, so attach btcprice to the external
btc-network there and reach it by service name at http://btcdata:4102.
deploy-citadel.sh creates the network on the remote if missing, as
btcdata's own deploy script already does.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TRkiLhK5qhkZjP2adxpA3e
2026-09-11 18:52:49 +02:00

3.5 KiB

btcprice

Bitcoin price tracker UI. Serves an HTML page with live price updates streamed from btcdata, which this server proxies over WebSocket and renders as HTML fragments for HTMX.

Quick Start

# Start btcdata first (provides price data)
cd ../btcdata && make run

# Local dev — creates .venv and installs requirements on first run
make run       # starts on port 4000
make tailwind  # watch Tailwind CSS (separate terminal)

Optionally cp .env.example .env to override BTCDATA_URL; without it the code default (http://localhost:4100) applies. make run-local requires a .env defining BTCDATA_LOCAL_URL.

Docker

docker compose up -d starts btcprice only — it does not bring up btcdata. Both compose files attach to the external btc-network, so create it once and start btcdata separately:

docker network create btc-network      # once
cd ../btcdata && docker compose up -d
cd ../btcprice && docker compose up -d
Service Local dev Docker
btcprice localhost:4000 localhost:4041 (container port 4040)
btcdata localhost:4100 localhost:4102

Inside btc-network, btcprice reaches btcdata as http://btcdata:4102.

Deployment (citadel)

./deploy-citadel.sh

Same method as ../elprice/deploy-citadel.sh: builds the image locally for the target's architecture (citadel is x86_64 → linux/amd64), copies docker-compose.citadel.yml and .env.citadel to /home/pmp/apps/btcprice on the host as docker-compose.yml / .env, pipes the image over SSH with docker save | docker load, and runs docker compose up -d --no-build. No registry involved.

Deployed btcprice listens on http://192.168.50.195:4041 and proxies to the btcdata running on citadel as well. Both attach to the external btc-network there, so BTCDATA_URL is http://btcdata:4102 (set in .env.citadel) — the service name inside the network, not a LAN address. The deploy script creates btc-network on the host if it does not exist yet.

Overridable: BTCPRICE_DEPLOY_HOST, BTCPRICE_DEPLOY_DIR, BTCPRICE_IMAGE_NAME, BTCPRICE_PLATFORM, BTCPRICE_NETWORK.

Environment Variables

Variable Default Description
BTCDATA_URL http://localhost:4100 btcdata service URL the server proxies to
BTCDATA_LOCAL_URL — Used by make run-local instead of BTCDATA_URL
DOCKER_BTCDATA_PORT 4102 btcdata's port inside btc-network (local compose only)
BTCPRICE_PORT 4041 Host port in the citadel deployment (.env.citadel)

The HTTP port is not configurable via environment: make run hardcodes 4000 and the Docker image's CMD hardcodes 4040.

How It Works

The browser loads a page with HTMX and the WebSocket extension, which connects back to btcprice at /ws/price and /ws/strike — the browser never contacts btcdata directly.

Each of those endpoints opens an upstream WebSocket to btcdata (/api/price/ws and /api/strike/ws), converts each JSON message to an HTML fragment (price_json_to_html, strike_json_to_html), and forwards it to the browser. HTMX swaps the received <div id="price-display"> / <div id="strike-display"> into the DOM. Price changes are color-coded (green up, red down). Reconnection is handled by HTMX.

Tech Stack

Python · FastAPI · Uvicorn · websockets · HTMX · Tailwind CSS v4

The Clojure implementation this replaced is on the clojure branch.