Merge branch 'dev' of http://git.ycjcjy.com/SpaceOfCheng/services into dev

controllers/book/book.go

 // GetBookList 获取图书列表
 func (c *BookController) GetBookList() {
 	caseIDs := c.GetString("caseid")
-	if caseIDs == "" {
+	if caseIDs == "" && c.Context.Get("cases") != nil {
 		cases := c.Context.Get("cases").([]model.SysUserCase)
 		caseIDs = c.GetCaseIDs(cases)
 	}