Abacus Microservice

Distributed running sum service with strong consistency.

Architecture

• FastAPI: Web framework
• Redis: Shared storage (atomic operations)
• 2 Nodes: Demonstrated locally

Run

docker-compose up --build

Starts:

• Redis on port 6379
• Node 1 on http://localhost:9001
• Node 2 on http://localhost:9002

Test

python tests/test_simple.py

API

POST /abacus/number

curl -X POST http://localhost:9001/abacus/number \
  -H "Content-Type: application/json" \
  -d '{"number": 10}'

GET /abacus/sum

curl http://localhost:9001/abacus/sum

DELETE /abacus/sum

curl -X DELETE http://localhost:9001/abacus/sum

Consistency

Redis INCRBY ensures atomic operations - no race conditions across nodes.