使用ShouldBindWith进行Golang / Gin表单字段验证

I am passing HTML form to data to a controller in Go. I am working off boilerplate to teach myself Go, and it includes form validation. The relevant statement, already changed somewhat from its original appearance in the boilerplate, is below:

if err := c.ShouldBindWith(&signinForm, binding.Form); err != nil {
      log.Println("err: ",err)
      c.JSON(406, gin.H{"message": "Invalid signin form", "form": signinForm})
      c.Abort()
      return
  }

The err logs as Key: 'SigninForm.Email' Error:Field validation for 'Email' failed on the 'email' tag.

In particular, I don't really know what c.ShouldBindWith(&signinForm, binding.Form) does (it was suggested by someone else in regards to my previous issue with signinForm being empty, which it solved).

How do I properly validate the form fields so that err == nil?