gem "redis-gcra"

redis = Redis.new
result = RedisGCRA.limit(
  redis: redis,
  key: "overall-account/bob@example.com",
  burst: 1000,
  rate: 100,
  period: 60, # seconds
  cost: 2
)
result.limited?    # => false - request should not be limited
result.remaining   # => 998   - remaining number of requests until limited
result.retry_after # => nil   - can retry without delay
result.reset_after # => ~0.6  - in 0.6 seconds rate limiter will completely reset
# call limit 499 more times in rapid succession and you get:
result.limited?    # => true  - request should be limited
result.remaining   # => 0     - no requests can be made at this point
result.retry_after # => ~1.2  - can retry in 1.2 seconds
result.reset_after # => ~600  - in 600 seconds rate limiter will completely reset

# Let's imagine `overall-account/bob@example.com` is limited.
# This will effectively reset limit for the key:
redis.del "overall-account/bob@example.com"

result = RedisGCRA.peek(
  redis: redis,
  key: "overall-account/bob@example.com",
  burst: 1000,
  rate: 100,
  period: 60 # seconds
)
result.limited?    # => true  - current state is limited
result.remaining   # => 0     - no requests can be made
result.retry_after # => ~0.6  - in 0.6 seconds remaining will become 1
result.reset_after # => ~600  - in 600 seconds rate limiter will completely reset