Scrum Solitare

Enterprise-style Scrum Poker application using Go, Gin, and SSE for real-time room updates.

Highlights

• Go backend with layered architecture (handlers, state, routes, config)
• Memory-first room state with disk synchronization to JSON files
• Real-time updates via Server-Sent Events (SSE)
• Strict state sanitization: unrevealed votes from other users are never broadcast
• Backend authorization for admin-only actions (reveal, reset)
• Themeable frontend with:
  • CSS architecture split into main.css, layout.css, and /themes/*
  • Theme options: win98 (default), modern, No Theme
  • Light/Dark mode independent from active theme
  • Desktop taskbar controls + mobile top controls for theme/mode switching
  • Config page and card deck preview
  • Drag-and-drop card ordering
  • Card add/remove with animation completion handling
  • Room password option
  • Room interface with voting area, participants, and admin controls
• Username persistence through localStorage

Project Layout

• src/main.go: app bootstrap
• src/config/: environment configuration
• src/server/: Gin engine setup
• src/routes/: page/api route registration
• src/handlers/: HTTP handlers (pages + API + SSE)
• src/state/: in-memory room manager, sanitization, persistence
• src/middleware/: static cache headers middleware
• src/models/: template page data models
• src/templates/: HTML templates (index.html, room.html)
• static/css/main.css: shared component primitives
• static/css/layout.css: grids/flex/positioning/responsive layout
• static/css/themes/: drop-in theme files
• static/js/ui-controls.js: global theme + mode engine
• static/js/: page logic (config.js, room.js)

Environment Variables

Quick Reference

• HOST (default: 0.0.0.0): network interface/address the server binds to.
• PORT (default: 8002): HTTP port the server listens on.
• DATA_PATH (default: ./data): folder where room JSON files are stored.
• MAX_ACTIVITY_LOG_ENTRIES (default: 400): max activity entries retained per room.
• ADMIN_LOG_BROADCAST_LIMIT (default: 200): max recent log entries sent to admins over SSE.
• STALE_ROOM_CLEANUP_INTERVAL (default: 5m): how often stale-room cleanup runs.
• STALE_ROOM_TTL (default: 30m): empty rooms older than this are deleted.

Variable Guide With Use Cases

HOST

• What it controls: where the web server is reachable from.
• Use case: local-only dev on one machine.

HOST=localhost PORT=8002 go run ./src

• Use case: allow access from LAN/Docker/k8s ingress.

HOST=0.0.0.0 PORT=8002 go run ./src

PORT

• What it controls: server port.
• Use case: avoid conflicts with another app already on 8002.

PORT=9000 go run ./src

• Use case: common reverse-proxy port mapping.

HOST=0.0.0.0 PORT=8080 go run ./src

DATA_PATH

• What it controls: disk location for persisted rooms.
• Use case: keep data in a dedicated local directory.

DATA_PATH=./tmp/rooms go run ./src

• Use case: persistent mount in containers.

docker run --rm -p 8002:8002 -e DATA_PATH=/app/data -v $(pwd)/data:/app/data scrum-solitare

MAX_ACTIVITY_LOG_ENTRIES

• What it controls: per-room in-memory/disk activity history cap.
• Use case: retain more history for auditing/debugging.

MAX_ACTIVITY_LOG_ENTRIES=1000 go run ./src

• Use case: reduce memory/storage in lightweight deployments.

MAX_ACTIVITY_LOG_ENTRIES=100 go run ./src

ADMIN_LOG_BROADCAST_LIMIT

• What it controls: maximum recent activity entries included in admin SSE payloads.
• Use case: richer admin timeline in active rooms.

ADMIN_LOG_BROADCAST_LIMIT=400 go run ./src

• Use case: smaller SSE payloads for lower bandwidth.

ADMIN_LOG_BROADCAST_LIMIT=50 go run ./src

STALE_ROOM_CLEANUP_INTERVAL

• What it controls: scheduler frequency for checking stale empty rooms.
• Use case: aggressive cleanup in ephemeral environments.

STALE_ROOM_CLEANUP_INTERVAL=1m go run ./src

• Use case: reduce cleanup churn in stable environments.

STALE_ROOM_CLEANUP_INTERVAL=15m go run ./src

STALE_ROOM_TTL

• What it controls: time since last room activity before an empty room is deleted.
• Use case: auto-prune quickly for temporary team rooms.

STALE_ROOM_TTL=10m go run ./src

• Use case: keep empty rooms around longer between sessions.

STALE_ROOM_TTL=2h go run ./src

Duration Format Notes

STALE_ROOM_CLEANUP_INTERVAL and STALE_ROOM_TTL use Go duration syntax:

• valid examples: 30s, 5m, 45m, 2h
• invalid examples: 5 (missing unit), five minutes

Run Locally

go mod tidy
go run ./src

Open http://localhost:8002.

Host binding examples:

HOST=localhost PORT=8002 go run ./src
HOST=0.0.0.0 PORT=8002 go run ./src

State tuning example:

MAX_ACTIVITY_LOG_ENTRIES=600 \
ADMIN_LOG_BROADCAST_LIMIT=300 \
STALE_ROOM_CLEANUP_INTERVAL=2m \
STALE_ROOM_TTL=45m \
go run ./src

Docker

Build:

docker build -t scrum-solitare .

Run:

docker run --rm -p 8002:8002 -e DATA_PATH=/app/data scrum-solitare

Real-Time Flow (SSE)

• Client joins room via POST /api/rooms/:roomID/join
• Client subscribes to GET /api/rooms/:roomID/events?participantId=...
• Server broadcasts sanitized room state updates on critical mutations:
  • room creation
  • join/leave
  • vote cast
  • reveal
  • reset