fix: add Azure channel support for /v1/responses/compact URL routing

[woan1136]

Problem

The Azure channel's GetRequestURL method in relay/channel/openai/adaptor.go only handles RelayModeResponses but misses RelayModeResponsesCompact. When Codex CLI/IDE triggers context compaction via POST /v1/responses/compact, requests routed through an Azure channel fall through to the generic deployments URL pattern, producing:

/openai/deployments/{model}/responses/compact?api-version=xxx

Azure doesn't recognize this path and returns 404.

Fix

Extend the existing RelayModeResponses condition (line 139) to also match RelayModeResponsesCompact, and append /compact to subUrl when in compact mode.

URL comparison (before → after)

Scenario	Before (broken)	After (fixed)
Normal Azure	/openai/deployments/{model}/responses/compact?api-version=xxx	/openai/v1/responses/compact?api-version=preview
cognitiveservices.azure.com	same broken pattern	/openai/responses/compact?api-version={apiVersion}
Custom AzureResponsesVersion	ignored for compact	properly respected

Changes

• relay/channel/openai/adaptor.go: 7 lines changed (2 modified + 5 added)

Testing

• Verified URL generation logic for all three Azure URL variants (normal, cognitiveservices, custom version)
• Confirmed that non-compact /v1/responses routing remains unchanged
• Response handling side (DoResponse, line 634) already has the RelayModeResponsesCompact case, so only the URL routing was missing

Summary by CodeRabbit

New Features

• Added Azure OpenAI compact response mode support, enabling more efficient response handling alongside standard responses.

[Copilot]

Pull request overview

Fixes Azure OpenAI URL generation for the /v1/responses/compact endpoint by ensuring Azure channels route compaction requests to the correct “responses API” path (instead of the deployments-based path that Azure 404s).

Changes:

• Extend Azure GetRequestURL responses-API special-case to include RelayModeResponsesCompact.
• Append /compact to the Azure responses sub-path when in compact mode.
• Preserve existing behavior for standard /v1/responses and non-responses endpoints.

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[coderabbitai]

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

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📥 Commits

Reviewing files that changed from the base of the PR and between 78e4cb3 and 902d368.

📒 Files selected for processing (1)

• relay/channel/openai/adaptor.go

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Walkthrough

The change extends Azure OpenAI responses request URL construction to handle a new relay mode (RelayModeResponsesCompact) by appending a /compact subpath to the responses endpoint while maintaining existing API version selection logic.

Changes

Cohort / File(s)	Summary
Azure OpenAI Responses URL Handling relay/channel/openai/adaptor.go	Added conditional logic to append /compact subpath to responses endpoint URL for RelayModeResponsesCompact mode, separate from standard RelayModeResponses handling.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Possibly related PRs

• feat: /v1/messages -> /v1/responses #2889: Modifies relay/channel/openai/adaptor.go's URL path selection for Responses/ResponsesCompact modes with similar endpoint construction logic.
• 修复Azure渠道对responses API的兼容性支持 - 为Azure渠道添加对responses API的特殊处理 - 兼容微软新… #1205: Extends Azure channel URL construction in adaptor.go's GetRequestURL for the responses relay mode with special-case path/version handling.
• feat: /v1/responses qwen3 max && perplexity #2803: Modifies OpenAI responses flow routing and request fields, adding /v1/responses endpoint support.

Poem

🐰 A compact twist, a path so neat,
/compact appended, the change complete,
Azure URLs now know the way,
To serve responses, compact today! ✨

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main fix: adding Azure channel support for /v1/responses/compact URL routing, which is the core change in the pull request.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[seefs001]

有Azure支持的文档地址吗？这个compact之前Azure是不支持的

[woan1136]

有Azure支持的文档地址吗？这个compact之前Azure是不支持的

这是 Azure 官方文档中关于 Compact a response 端点的说明：

📄 Azure OpenAI Responses API - Compact a response
https://learn.microsoft.com/en-us/azure/foundry/openai/how-to/responses?tabs=rest-api#compact-a-response

以及 OpenAI 官方 API 参考文档：
https://developers.openai.com/api/reference/resources/responses/methods/compact

Compact 端点（POST /responses/compact）是 Responses API 的一部分。Azure 通过 /openai/v1/responses/compact（或 cognitiveservices.azure.com 域名下的 /openai/responses/compact）提供支持，URL 规则与 /openai/v1/responses 一致。

我们已在实际的 Azure OpenAI 资源上验证了这个修复，compact 请求能够正确路由并返回有效的 response.compaction 响应对象。