Example: High-Availability Data Fetcher (Endpoint Rotation)

[cinar]

Description: When fetching time-sensitive market data, relying on a single upstream provider is a single point of failure. This example will show how to use Resile's stateful retries to seamlessly rotate through fallback HTTP endpoints.

• Architecture & Implementation Requirements:

  • Setup: Create examples/http_rotation/main.go.
  • Configuration: Define a slice of backend URLs: ["api.primary-data.com", "api.backup-vendor.com", "api.fallback.com"].
  • Execution: Use resile.DoState. In the closure, use state.Attempt and the modulo operator (%) to select the URL from the slice.
  • Failure Emulation: Use aggressive, low-timeout configurations (e.g., 500ms) on the HTTP client so that if the primary provider is lagging, Resile instantly cancels the context and fires the next attempt at the backup vendor.

• Acceptance Criteria:

  • Demonstrate how to keep the HTTP client instantiated outside the retry loop to reuse TCP connections (Keep-Alives).
  • Demonstrate returning the successfully fetched JSON payload using Go generics.

[cinar]

#oncu please first give a plan