Load balance support

[linglingye001]

No description provided.

[Copilot]

Pull Request Overview

This PR implements load balancing support for the Azure App Configuration client, allowing for distributed load across multiple replicas when multiple endpoints are available.

• Adds a new LoadBalancingEnabled option to control load balancing behavior
• Implements client rotation logic to distribute requests across available replicas
• Adds tracing support to track when load balancing is enabled

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
azureappconfiguration/options.go	Adds LoadBalancingEnabled configuration option
azureappconfiguration/internal/tracing/tracing.go	Adds load balancing tracing support and tags
azureappconfiguration/azureappconfiguration.go	Implements core load balancing logic with client rotation
azureappconfiguration/failover_test.go	Comprehensive test coverage for load balancing functionality

[Copilot]

The rotateSliceInPlace function lacks documentation explaining its purpose, parameters, and the reverse-reverse algorithm it implements. Consider adding a docstring that explains the algorithm and its time/space complexity.

Suggested change

	// rotateSliceInPlace rotates a slice left by k positions using the reverse-reverse algorithm.
	// rotateSliceInPlace rotates a slice left by k positions in place using the reverse-reverse algorithm.
	//
	// Parameters:
	// slice: The slice to be rotated. The rotation is performed in place.
	// k: The number of positions to rotate the slice to the left. If k >= len(slice), k is reduced modulo len(slice).
	//
	// Algorithm:
	// The function uses the reverse-reverse algorithm:
	// 1. Reverse the entire slice.
	// 2. Reverse the first len(slice)-k elements.
	// 3. Reverse the remaining k elements.
	// This results in the slice being rotated left by k positions.
	//
	// Time Complexity: O(n), where n is the length of the slice.
	// Space Complexity: O(1), as the rotation is performed in place.

[Copilot]

The rotateClientsToNextEndpoint function lacks documentation. It should include a docstring explaining its purpose, parameters, and how it modifies the clients slice in-place for load balancing.

Suggested change

	// rotateClientsToNextEndpoint rotates the clients slice in-place so that the client following
	// the last successful endpoint becomes the first element. This is used for load balancing
	// across multiple endpoints. If the last successful endpoint is found, the slice is rotated
	// to start with the next client. If there is only one client or the endpoint is not found,
	// the slice is not modified.
	//
	// Parameters:
	// - clients: A slice of pointers to configurationClientWrapper. This slice is modified in-place.
	// - lastSuccessfulEndpoint: The endpoint string of the last successful client.

[RichardChen820]

LGTM