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

backend/internal/pkg/gemini/models.go

@@ -0,0 +1,63 @@
+// Package gemini provides minimal fallback model metadata for Gemini native endpoints.
+// It is used when upstream model listing is unavailable (e.g. OAuth token missing AI Studio scopes).
+package gemini
+
+import "strings"
+
+type Model struct {
+	Name                       string   `json:"name"`
+	DisplayName                string   `json:"displayName,omitempty"`
+	Description                string   `json:"description,omitempty"`
+	SupportedGenerationMethods []string `json:"supportedGenerationMethods,omitempty"`
+}
+
+type ModelsListResponse struct {
+	Models []Model `json:"models"`
+}
+
+func DefaultModels() []Model {
+	methods := []string{"generateContent", "streamGenerateContent"}
+	return []Model{
+		{Name: "models/gemini-2.0-flash", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-2.5-flash", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-2.5-flash-image", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-2.5-pro", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-3.5-flash", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-3-flash-preview", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-3-pro-preview", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-3.1-pro-preview", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-3.1-pro-preview-customtools", SupportedGenerationMethods: methods},
+		{Name: "models/gemini-3.1-flash-image", SupportedGenerationMethods: methods},
+	}
+}
+
+func HasFallbackModel(model string) bool {
+	trimmed := strings.TrimSpace(model)
+	if trimmed == "" {
+		return false
+	}
+	if !strings.HasPrefix(trimmed, "models/") {
+		trimmed = "models/" + trimmed
+	}
+	for _, model := range DefaultModels() {
+		if model.Name == trimmed {
+			return true
+		}
+	}
+	return false
+}
+
+func FallbackModelsList() ModelsListResponse {
+	return ModelsListResponse{Models: DefaultModels()}
+}
+
+func FallbackModel(model string) Model {
+	methods := []string{"generateContent", "streamGenerateContent"}
+	if model == "" {
+		return Model{Name: "models/unknown", SupportedGenerationMethods: methods}
+	}
+	if len(model) >= 7 && model[:7] == "models/" {
+		return Model{Name: model, SupportedGenerationMethods: methods}
+	}
+	return Model{Name: "models/" + model, SupportedGenerationMethods: methods}
+}

backend/internal/pkg/gemini/models_test.go

@@ -0,0 +1,43 @@
+package gemini
+
+import "testing"
+
+func TestDefaultModels_ContainsFallbackCatalogModels(t *testing.T) {
+	t.Parallel()
+
+	models := DefaultModels()
+	byName := make(map[string]Model, len(models))
+	for _, model := range models {
+		byName[model.Name] = model
+	}
+
+	required := []string{
+		"models/gemini-2.5-flash-image",
+		"models/gemini-3.1-pro-preview-customtools",
+		"models/gemini-3.1-flash-image",
+	}
+
+	for _, name := range required {
+		model, ok := byName[name]
+		if !ok {
+			t.Fatalf("expected fallback model %q to exist", name)
+		}
+		if len(model.SupportedGenerationMethods) == 0 {
+			t.Fatalf("expected fallback model %q to advertise generation methods", name)
+		}
+	}
+}
+
+func TestHasFallbackModel_RecognizesCustomtoolsModel(t *testing.T) {
+	t.Parallel()
+
+	if !HasFallbackModel("gemini-3.1-pro-preview-customtools") {
+		t.Fatalf("expected customtools model to exist in fallback catalog")
+	}
+	if !HasFallbackModel("models/gemini-3.1-pro-preview-customtools") {
+		t.Fatalf("expected prefixed customtools model to exist in fallback catalog")
+	}
+	if HasFallbackModel("gemini-unknown") {
+		t.Fatalf("did not expect unknown model to exist in fallback catalog")
+	}
+}