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TTL Caching for Microservices
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TTL Caching for Microservices

HardPython

Problem

Implement a custom caching mechanism with Time-To-Live (TTL) expiration for high-frequency API responses in a distributed microservices environment. Implement ttl_cache(operations, ttl) using simulated timestamps. Each operation is ['set', key, value, timestamp] or ['get', key, timestamp]; return the values from GET operations in order, using -1 for misses or expired entries. An entry expires when current_time >= insertion_time + ttl.

Constraints

  • 1 <= len(operations) <= 1000
  • 1 <= ttl <= 10^9
  • Each operation is either ['set', key, value, timestamp] or ['get', key, timestamp]
  • key and value are non-empty strings
  • 0 <= timestamp <= 10^9
  • Operation timestamps are nondecreasing
  • SET values and GET results are compared as strings; cache misses return -1

Function Signature

def ttl_cache(operations, ttl):
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