feat(router): support hive as source for supergraph

[dotansimha]

Closes #439

• fetch supergraph from CDN
• config to fetch
• TLS fix
• polling interval
• swaping of supergraph state
• etag support
• error handling
• ? supergraph checksum

[gemini-code-assist]

Summary of Changes

Hello @dotansimha, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the router's operational flexibility by introducing new capabilities for supergraph schema management and secure subgraph communication. It allows the router to dynamically fetch its supergraph configuration from a centralized Hive Console CDN and ensures that all interactions with subgraphs are conducted over secure HTTPS connections, improving both deployment options and data integrity.

Highlights

• New Supergraph Source: Hive Console CDN: The router now supports fetching the supergraph schema directly from the Hive Console CDN. This introduces a new hive source type in the configuration, requiring an endpoint and an API key.
• Enhanced HTTPS Connectivity for Subgraphs: The subgraph executors have been upgraded to utilize an HTTPS connector, improving secure communication with backend services. This change specifically integrates hyper-tls for robust TLS support in HTTP client operations.
• Refactored Supergraph Loading Logic: The internal mechanism for loading supergraph definitions has been significantly refactored. A new SupergraphLoader trait and its implementations (SupergraphFileLoader, SupergraphHiveConsoleLoader) centralize and abstract the process of retrieving the supergraph schema, making it more flexible and extensible.

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[gemini-code-assist]

Code Review

This pull request introduces two main features: the ability to load the supergraph from a Hive CDN endpoint, and support for HTTPS connectors when communicating with subgraphs. The changes are well-structured, introducing a new supergraph module to handle different loading strategies. The implementation for HTTPS support in the executor is also correct. I have a couple of suggestions to improve robustness and error handling.

[github-actions]

✅ k6-benchmark results

     ✓ response code was 200
     ✓ no graphql errors
     ✓ valid response structure

     █ setup

     checks.........................: 100.00% ✓ 236823      ✗ 0    
     data_received..................: 6.9 GB  230 MB/s
     data_sent......................: 93 MB   3.1 MB/s
     http_req_blocked...............: avg=3.15µs   min=691ns   med=1.74µs  max=19.85ms  p(90)=2.45µs  p(95)=2.83µs  
     http_req_connecting............: avg=204ns    min=0s      med=0s      max=868.55µs p(90)=0s      p(95)=0s      
     http_req_duration..............: avg=18.58ms  min=1.79ms  med=17.62ms max=229.81ms p(90)=25.67ms p(95)=28.72ms 
       { expected_response:true }...: avg=18.58ms  min=1.79ms  med=17.62ms max=229.81ms p(90)=25.67ms p(95)=28.72ms 
     http_req_failed................: 0.00%   ✓ 0           ✗ 78961
     http_req_receiving.............: avg=146.66µs min=24.92µs med=38.66µs max=203.67ms p(90)=86.02µs p(95)=366.83µs
     http_req_sending...............: avg=23.7µs   min=5.29µs  med=10.42µs max=23.09ms  p(90)=15.72µs p(95)=27.41µs 
     http_req_tls_handshaking.......: avg=0s       min=0s      med=0s      max=0s       p(90)=0s      p(95)=0s      
     http_req_waiting...............: avg=18.41ms  min=1.75ms  med=17.5ms  max=112.1ms  p(90)=25.43ms p(95)=28.43ms 
     http_reqs......................: 78961   2627.100821/s
     iteration_duration.............: avg=18.99ms  min=5.34ms  med=17.99ms max=257.1ms  p(90)=26.14ms p(95)=29.22ms 
     iterations.....................: 78941   2626.435404/s
     vus............................: 50      min=50        max=50 
     vus_max........................: 50      min=50        max=50 

[github-actions]

🐋 This PR was built and pushed to the following Docker images:

Image Names: ghcr.io/graphql-hive/router

Platforms: linux/amd64,linux/arm64

Image Tags: ghcr.io/graphql-hive/router:pr-400 ghcr.io/graphql-hive/router:sha-3cbf81d

Docker metadata

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