feat: 依据 LLM 参数实例化 client

backend/internal/llm/client.go

@@ -0,0 +1,29 @@
+package llm
+
+import (
+	"fmt"
+	"knowledge-graph-backend/internal/config"
+
+	"github.com/tmc/langchaingo/llms"
+	"github.com/tmc/langchaingo/llms/openai"
+)
+
+type Client struct {
+	llm llms.Model
+	config config.LLMConfig
+}
+
+// 创建 LLM 实例
+func NewClient(cfg config.LLMConfig) (*Client, error) {
+	model, err := openai.New(
+		openai.WithToken(cfg.APIKey),
+		openai.WithBaseURL(cfg.BaseURL),
+		openai.WithModel(cfg.Model),
+	)
+
+	if err != nil {
+        return nil, fmt.Errorf("failed to create llm client: %w", err)
+    }
+
+	return &Client{config: cfg, llm: model}, nil
+}

backend/internal/llm/client_test.go

@@ -0,0 +1,37 @@
+package llm
+
+import (
+	"knowledge-graph-backend/internal/config"
+	"log"
+	"testing"
+)
+
+func TestNewClient(t *testing.T) {
+	cfg, err := config.Load()
+	if err != nil {
+		log.Printf("[WARN] config.Load() returned error: %v, using default config", err)
+	} else {
+		log.Printf("[INFO] config loaded successfully, LLM config: %+v", cfg.LLM)
+	}
+
+	client, err := NewClient(cfg.LLM)
+	if err != nil {
+		t.Fatalf("NewClient() returned unexpected error: %v", err)
+	}
+	log.Printf("[INFO] NewClient() succeeded, client created")
+
+	// 验证返回的 Client 实例不为 nil
+	if client == nil {
+		t.Fatal("NewClient() returned nil client")
+	}
+	log.Printf("[INFO] client instance is non-nil, validation passed")
+
+	// 验证 llm 实例被成功创建（不调用，只检查非 nil）
+	if client.llm == nil {
+		t.Error("client.llm is nil, expected a non-nil llms.Model")
+	} else {
+		log.Printf("[INFO] client.llm is non-nil, llms.Model created successfully")
+	}
+
+	log.Printf("[INFO] TestNewClient completed successfully")
+}