move request_builder into internal pkg (#304) (#329)

* move request_builder into internal pkg (#304)

* add some test for internal.RequestBuilder

* add a test for openai.GetEngine

engines_test.go

@@ -0,0 +1,34 @@
+package openai_test
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"testing"
+
+	. "github.com/sashabaranov/go-openai"
+	"github.com/sashabaranov/go-openai/internal/test"
+	"github.com/sashabaranov/go-openai/internal/test/checks"
+)
+
+// TestGetEngine Tests the retrieve engine endpoint of the API using the mocked server.
+func TestGetEngine(t *testing.T) {
+	server := test.NewTestServer()
+	server.RegisterHandler("/v1/engines/text-davinci-003", func(w http.ResponseWriter, r *http.Request) {
+		resBytes, _ := json.Marshal(Engine{})
+		fmt.Fprintln(w, string(resBytes))
+	})
+	// create the test server
+	ts := server.OpenAITestServer()
+	ts.Start()
+	defer ts.Close()
+
+	config := DefaultConfig(test.GetTestToken())
+	config.BaseURL = ts.URL + "/v1"
+	client := NewClientWithConfig(config)
+	ctx := context.Background()
+
+	_, err := client.GetEngine(ctx, "text-davinci-003")
+	checks.NoError(t, err, "GetEngine error")
+}