How to check if a parameter is passed in?

[zcfh]

type queryConfInfoHandler struct {
	ConfName  string `json:"conf_name"`
}

For example, in the struct above, how do I know whether conf_name is passed in the client's json? Because it is null when it is not passed in, but it is also possible that the client passed in a empty value.

One way I know is to change the type to *string to determine whether the field is nil. I want to know if the gin framework has some built-in checking capabilities.

[r0ld3x]

what do you get when you are doing c.BindJson(&queryConfInfo)

[zcfh]

what do you get when you are doing c.BindJson(&queryConfInfo)

conf_name == ""
Even if there is no conf_name in the requested json, conf_name will still be initialized to zero value.

[r0ld3x]

yes that's the limitation I see in go.

So I would try to use some validation and *string this is what we have I guess.

[FarmerChillax]

refs:

• proposal: Allow differentiating between a nil string and an empty string golang/go#44219 (comment)
• https://stackoverflow.com/questions/23727866/properly-distinguish-between-not-set-nil-and-blank-empty-value