Merge pull request #7562 from william-drakemond/fix/opencode-zen-deepseek-reasoning-placeholder

fix(openai): inject DeepSeek reasoning placeholder for OpenCode Zen upstream

backend/internal/service/openai_gateway_deepseek_chat_reasoning_test.go

@@ -87,6 +87,66 @@ func TestEnsureDeepSeekChatReasoningPlaceholders(t *testing.T) {
 	})
 }
 
+// OpenCode Zen / Go 把 deepseek-* 模型转发给 DeepSeek，同一条 thinking-mode 400
+// 会原样回吐，占位注入必须覆盖这条链路；同账号下的非 DeepSeek 模型不受影响。
+func TestEnsureDeepSeekChatReasoningPlaceholders_OpenCodeZenUpstream(t *testing.T) {
+	openCodeGo := &Account{
+		ID:          24,
+		Name:        "opencode-go",
+		Platform:    PlatformOpenCodeGo,
+		Type:        AccountTypeAPIKey,
+		Credentials: map[string]any{"api_key": "sk-test", "base_url": DefaultOpenCodeGoBaseURL},
+	}
+	openAIViaZen := &Account{
+		ID:          25,
+		Platform:    PlatformOpenAI,
+		Type:        AccountTypeAPIKey,
+		Credentials: map[string]any{"api_key": "sk-test", "base_url": DefaultOpenCodeZenBaseURL},
+	}
+	thirdPartyDeepSeekName := &Account{
+		ID:          26,
+		Platform:    PlatformOpenAI,
+		Type:        AccountTypeAPIKey,
+		Credentials: map[string]any{"api_key": "sk-test", "base_url": "http://upstream.example"},
+	}
+
+	missingFor := func(model string) []byte {
+		return []byte(`{"model":"` + model + `","messages":[{"role":"user","content":"hi"},{"role":"assistant","content":"","tool_calls":[{"id":"call_1","type":"function","function":{"name":"exec","arguments":"{}"}}]},{"role":"tool","tool_call_id":"call_1","content":"ok"}]}`)
+	}
+
+	t.Run("opencode_go_deepseek_model_fills_empty_assistant", func(t *testing.T) {
+		body := missingFor("deepseek-v4.1-flash")
+		got := ensureDeepSeekChatReasoningPlaceholders(openCodeGo, body)
+		require.Equal(t, deepSeekChatReasoningPlaceholderText, gjson.GetBytes(got, "messages.1.reasoning_content").String())
+		require.False(t, gjson.GetBytes(got, "messages.0.reasoning_content").Exists())
+		require.False(t, gjson.GetBytes(got, "messages.2.reasoning_content").Exists())
+	})
+
+	t.Run("opencode_go_non_deepseek_model_unchanged", func(t *testing.T) {
+		body := missingFor("glm-5.3")
+		got := ensureDeepSeekChatReasoningPlaceholders(openCodeGo, body)
+		require.Equal(t, string(body), string(got))
+	})
+
+	t.Run("opencode_prefixed_model_id_fills_empty_assistant", func(t *testing.T) {
+		body := missingFor("opencode-go/DeepSeek-V4-Pro")
+		got := ensureDeepSeekChatReasoningPlaceholders(openCodeGo, body)
+		require.Equal(t, deepSeekChatReasoningPlaceholderText, gjson.GetBytes(got, "messages.1.reasoning_content").String())
+	})
+
+	t.Run("openai_platform_pointed_at_zen_host_fills_empty_assistant", func(t *testing.T) {
+		body := missingFor("deepseek-v4-flash")
+		got := ensureDeepSeekChatReasoningPlaceholders(openAIViaZen, body)
+		require.Equal(t, deepSeekChatReasoningPlaceholderText, gjson.GetBytes(got, "messages.1.reasoning_content").String())
+	})
+
+	t.Run("unrelated_upstream_with_deepseek_model_name_unchanged", func(t *testing.T) {
+		body := missingFor("deepseek-v4.1-flash")
+		got := ensureDeepSeekChatReasoningPlaceholders(thirdPartyDeepSeekName, body)
+		require.Equal(t, string(body), string(got))
+	})
+}
+
 type reasoningHitCache struct {
 	stubGatewayCache
 	values map[string]string

backend/internal/service/openai_gateway_responses_chat_fallback.go

@@ -431,15 +431,53 @@ func targetsDeepSeekAPIHost(account *Account) bool {
 	return strings.EqualFold(u.Hostname(), ds.Hostname())
 }
 
+// targetsOpenCodeZenUpstream 报告该账号上游是否是官方 OpenCode Zen / Go 网关。
+// platform=opencode_go 直接命中；其他平台按 base_url 主机判定，覆盖用 API Key
+// 直接把 openai 平台账号指向 opencode.ai 的接入方式。
+func targetsOpenCodeZenUpstream(account *Account) bool {
+	if account == nil {
+		return false
+	}
+	if account.IsOpenCodeGo() {
+		return true
+	}
+	return isOfficialOpenCodeHost(account.GetOpenAIBaseURL())
+}
+
+// isDeepSeekCatalogModel 判定（剥掉 opencode 前缀后的）模型 ID 是否属于
+// DeepSeek 系列，例如 deepseek-v4-flash / deepseek-v4.1-flash / deepseek-chat。
+func isDeepSeekCatalogModel(model string) bool {
+	return strings.HasPrefix(normalizeOpenCodeGoModelID(model), "deepseek")
+}
+
+// requiresDeepSeekChatReasoning 报告该 Chat Completions 请求的上游是否按
+// DeepSeek thinking mode 语义校验 reasoning_content。
+//
+// DeepSeek 官方 API 直接命中。OpenCode Zen / Go 是转发型订阅网关：deepseek-*
+// 模型由 DeepSeek 实际承载，同一条 400 原文会被一字不差地回吐，所以按
+// 「官方 OpenCode 上游 + deepseek-* 模型」补一条判定。
+//
+// 不放宽成「任意上游的 deepseek-* 模型名」：占位符是写进请求体的额外字段，
+// 对没有这条约束的上游属于无谓改写，且可能触发未知字段校验。
+func requiresDeepSeekChatReasoning(account *Account, body []byte) bool {
+	if targetsDeepSeekAPIHost(account) {
+		return true
+	}
+	if !targetsOpenCodeZenUpstream(account) {
+		return false
+	}
+	return isDeepSeekCatalogModel(gjson.GetBytes(body, "model").String())
+}
+
 // ensureDeepSeekChatReasoningPlaceholders 给缺 reasoning_content 的 assistant
 // 消息补单个空格占位。DeepSeek thinking mode 要求历史里每条产生过思维的
 // assistant 消息都回传该字段，否则 400
 // "The `reasoning_content` in the thinking mode must be passed back to the API"。
 //
 // 桥接会从 summary / 缓存回注真实明文；这里只填仍为空的缺口，不覆盖已有内容。
-// 非 DeepSeek 上游原样返回（字节不变）。
+// 判定见 requiresDeepSeekChatReasoning，不命中的上游原样返回（字节不变）。
 func ensureDeepSeekChatReasoningPlaceholders(account *Account, body []byte) []byte {
-	if !targetsDeepSeekAPIHost(account) {
+	if !requiresDeepSeekChatReasoning(account, body) {
 		return body
 	}
 	messages := gjson.GetBytes(body, "messages")