I'm trying to parse XML tag into a boolean if it exists. The tags inside <status>
can be <active />
, <available />
or <invalid />
and only one of these tag exists inside <status>
.
Here's my current attempt:
package main
import (
"encoding/xml"
"fmt"
)
type Response struct {
XMLName xml.Name `xml:"domain"`
Authority string `xml:"authority,attr"`
RegistryType string `xml:"registryType,attr"`
EntityClass string `xml:"entityClass,attr"`
EntityName string `xml:"entityName,attr"`
DomainName string `xml:"domainName"`
Status Status `xml:"status"`
}
type Status struct {
Active bool `xml:"active,omitempty"`
Available bool `xml:"available,omitempty"`
Invalid bool `xml:"invalid,omitempty"`
}
func main() {
str := `
<domain authority="domain.fi" registryType="dchk1" entityClass="domain-name" entityName="esimerkki.fi">
<domainName>esimerkki.fi</domainName>
<status>
<active />
</status>
</domain>
`
var ans Response
err := xml.Unmarshal([]byte(str), &ans)
if err != nil {
panic(err)
}
fmt.Printf(`%#v`, ans.Status)
}
This returns all Status.*
as false
and not Status.Active = true
as expected. How can you get the expected result?
Second attempt with pointers:
type Status struct {
Active *bool `xml:"active,omitempty"`
Available *bool `xml:"available,omitempty"`
Invalid *bool `xml:"invalid,omitempty"`
}
*ans.Status.Active
still false
.
As @mh-cbon suggested simply checking for if pointer wasn't nil
for *bool
was enough to determine if that tag existed. But I went and turned the XML response struct into proper Response
struct which only contains needed information and Status
into a constant.
So now it's:
// Raw XML DTO
type XmlResponse struct {
XMLName xml.Name `xml:"domain"`
Authority string `xml:"authority,attr"`
RegistryType string `xml:"registryType,attr"`
EntityClass string `xml:"entityClass,attr"`
EntityName string `xml:"entityName,attr"`
DomainName string `xml:"domainName"`
Status XmlStatus `xml:"status"`
}
// Raw XML DTO
type XmlStatus struct {
Active *bool `xml:"active,omitempty"`
Available *bool `xml:"available,omitempty"`
Invalid *bool `xml:"invalid,omitempty"`
}
// Return Response struct which doesn't have the unnecessary XML
func (x XmlResponse) GetResponse() Response {
st := Invalid // Default to invalid
if x.Status.Active != nil {
st = Active
} else if x.Status.Available != nil {
st = Available
} else if x.Status.Invalid != nil {
st = Invalid
}
return Response{
Domain: x.DomainName,
Status: st,
}
}
// Proper response parsed from XML
type Response struct {
Domain string
Status Status
}
type Status uint8
const (
Invalid Status = iota
Active
Available
)
And parsing happens as:
var xmlresp XmlResponse
err := xml.Unmarshal([]byte(str), &xmlresp)
if err != nil {
panic(err)
}
ans := xmlresp.GetResponse()
fmt.Printf(`%#v`, ans)