Caching Flow

The Caching Flow is designed to enhance API performance and reliability by caching responses to frequently accessed API requests. This reduces the load on API providers, and improves response times for consumers. Caching based on URL, query parameters and specific headers are supported.

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Scenarios

1. Reduced Latency: Serve responses faster by avoiding redundant API calls for frequently accessed data.
2. Cost Optimization: Reduce API call costs by minimizing requests to third-party providers.
3. Failover Support: Provide cached data when APIs are unavailable or experience downtime.
4. Header-Based Differentiation: Enable cache rules based on headers for advanced use cases like user-specific data or subscription tiers.

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Flow Components

• Read Cache Processor
• Write Cache Processor

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Flow Example

name: CachingFlow

filter:
  url: httpbin.com/*
processors:
  ReadCache:
    processor: ReadCache 
    parameters:
      - key: caching_key_parts
        value:
          - $.request.headers.api_key
          - $.request.query_param.resource_id
  WriteCache:
    processor: WriteCache 
    parameters:
      - key: ttl_seconds
        value: 600 
      - key: record_max_size_bytes
        value: 8192 
      - key: max_cache_size_mb
        value: 200 
      - key: caching_key_parts
        value:
          - $.request.headers.api_key
          - $.request.query_param.resource_id
flow:
  request:
    - from:
        stream:
          name: globalStream
          at: start
      to:
        processor:
          name: ReadCache
    - from:
        processor:
          name: ReadCache
          condition: cache_miss
      to:
        stream:
          name: globalStream
          at: end
  response:
    - from:
        stream:
          name: globalStream
          at: start
      to:
        processor:
          name: WriteCache
    - from:
        processor:
          name: WriteCache
      to:
        stream:
          name: globalStream
          at: end
    - from:
        processor:
          name: ReadCache
          condition: cache_hit
      to:
        stream:
          name: globalStream
          at: end

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Troubleshooting

Ensure caching_key_parts is consistent between Read Cache and Write Cache processors.