Sub2API v1.0 - AI API 网关（二开初始版本，基于上游 Wei-Shaw/sub2api）

backend/internal/service/openai_apikey_responses_probe_verdict_test.go

@@ -0,0 +1,176 @@
+package service
+
+import (
+	"context"
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/openai_compat"
+	"github.com/stretchr/testify/require"
+)
+
+func newResponsesProbeAccount(id int64) Account {
+	return Account{
+		ID:          id,
+		Platform:    PlatformOpenAI,
+		Type:        AccountTypeAPIKey,
+		Name:        "compat-upstream",
+		Concurrency: 1,
+		Credentials: map[string]any{
+			"api_key":  "sk-test",
+			"base_url": "https://compat-upstream.example/v1",
+		},
+	}
+}
+
+// runResponsesProbe 跑一次探测，返回落库的 extra 更新；未落库时返回 nil。
+func runResponsesProbe(t *testing.T, status int, body string) map[string]any {
+	t.Helper()
+	account := newResponsesProbeAccount(4200)
+	// 带缓冲且不阻塞：探测决定不落标时通道应保持为空。
+	updateCalls := make(chan map[string]any, 1)
+	repo := &snapshotUpdateAccountRepo{
+		stubOpenAIAccountRepo: stubOpenAIAccountRepo{accounts: []Account{account}},
+		updateExtraCalls:      updateCalls,
+	}
+	svc := &AccountTestService{
+		accountRepo: repo,
+		httpUpstream: &httpUpstreamRecorder{resp: &http.Response{
+			StatusCode: status,
+			Header:     make(http.Header),
+			Body:       io.NopCloser(strings.NewReader(body)),
+		}},
+		cfg: &config.Config{Security: config.SecurityConfig{URLAllowlist: config.URLAllowlistConfig{Enabled: false}}},
+	}
+
+	svc.ProbeOpenAIAPIKeyResponsesSupport(context.Background(), account.ID)
+
+	select {
+	case updates := <-updateCalls:
+		return updates
+	default:
+		return nil
+	}
+}
+
+// issue #5371：账号一旦被落标为「不支持 Responses」，网关就长期改走
+// /v1/chat/completions，Codex 的 prompt 缓存前缀被打散；而探测只在账号创建/更新时
+// 跑一次，标记不会自动恢复。因此判据不成立的响应绝不能落标。
+func TestProbeOpenAIAPIKeyResponsesSupport_InconclusiveResponseKeepsUnknown(t *testing.T) {
+	cases := []struct {
+		name string
+		body string
+	}{
+		{
+			// 探测请求自带 openaiResponsesProbeMaxOutputTokens 预算，推理型模型可能
+			// 把预算烧在 reasoning 上就被截断——没有 function_call 是预算不足所致。
+			name: "incomplete_max_output_tokens",
+			body: `{"status":"incomplete","incomplete_details":{"reason":"max_output_tokens"},` +
+				`"output":[{"type":"reasoning","summary":[]}]}`,
+		},
+		{
+			// HTTP 200 携带的失败响应是上游瞬时故障，不构成工具能力证据。
+			name: "failed_status_on_http_200",
+			body: `{"status":"failed","error":{"code":"server_error","message":"upstream hiccup"},"output":[]}`,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			require.Nil(t, runResponsesProbe(t, http.StatusOK, tc.body),
+				"判据不成立时必须保持 unknown，不得落标")
+		})
+	}
+}
+
+// 对照不变式：能下结论的响应仍要落标，否则「不落标」写宽了就等于把整个探测废掉。
+func TestProbeOpenAIAPIKeyResponsesSupport_ConclusiveResponsesStillPersist(t *testing.T) {
+	cases := []struct {
+		name   string
+		status int
+		body   string
+		want   bool
+	}{
+		{
+			name:   "completed_with_function_call",
+			status: http.StatusOK,
+			body:   `{"status":"completed","output":[{"type":"function_call","name":"probe_ping"}]}`,
+			want:   true,
+		},
+		{
+			// 火山方舟 coding/v3 × kimi-k2.6：端点在、跑完了、就是不产出 function_call。
+			// 这正是探测要抓的目标，必须继续落标为不支持。
+			name:   "completed_reasoning_only",
+			status: http.StatusOK,
+			body:   `{"status":"completed","output":[{"type":"reasoning"}]}`,
+			want:   false,
+		},
+		{
+			// 非 max_output_tokens 的截断（如内容过滤）不在放行范围内，维持原判定。
+			name:   "incomplete_other_reason",
+			status: http.StatusOK,
+			body:   `{"status":"incomplete","incomplete_details":{"reason":"content_filter"},"output":[]}`,
+			want:   false,
+		},
+		{
+			// 响应体没有 status 字段（第三方兼容上游常见）时维持既有行为。
+			name:   "no_status_field",
+			status: http.StatusOK,
+			body:   `{"output":[{"type":"function_call","name":"probe_ping"}]}`,
+			want:   true,
+		},
+		{
+			name:   "endpoint_absent_404",
+			status: http.StatusNotFound,
+			body:   `{"error":{"message":"Not Found"}}`,
+			want:   false,
+		},
+		{
+			// 非 2xx 的结论只看状态码：body 里的 status=failed 不该让它变成"不下结论"。
+			name:   "server_error_stays_conservative_true",
+			status: http.StatusInternalServerError,
+			body:   `{"status":"failed"}`,
+			want:   true,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			updates := runResponsesProbe(t, tc.status, tc.body)
+			require.NotNil(t, updates, "能下结论的响应必须落标")
+			require.Equal(t, tc.want, updates[openai_compat.ExtraKeyResponsesSupported])
+		})
+	}
+}
+
+func TestResponsesProbeVerdictIsConclusive(t *testing.T) {
+	cases := []struct {
+		name   string
+		status int
+		body   string
+		want   bool
+	}{
+		{"200_completed", 200, `{"status":"completed","output":[]}`, true},
+		{"200_incomplete_max_output_tokens", 200,
+			`{"status":"incomplete","incomplete_details":{"reason":"max_output_tokens"}}`, false},
+		{"200_incomplete_content_filter", 200,
+			`{"status":"incomplete","incomplete_details":{"reason":"content_filter"}}`, true},
+		{"200_incomplete_without_reason", 200, `{"status":"incomplete"}`, true},
+		{"200_failed", 200, `{"status":"failed"}`, false},
+		{"200_no_status_field", 200, `{"output":[]}`, true},
+		{"200_non_json", 200, `not-json`, true},
+		{"200_empty_body", 200, ``, true},
+		// 非 2xx 只看状态码，不读 body。
+		{"404_ignores_body_status", 404, `{"status":"failed"}`, true},
+		{"500_ignores_body_status", 500, `{"status":"incomplete","incomplete_details":{"reason":"max_output_tokens"}}`, true},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			require.Equal(t, tc.want, responsesProbeVerdictIsConclusive(tc.status, []byte(tc.body)))
+		})
+	}
+}