如何使用xml golang std查找已知属性和令牌的值。 LIB

Question

I'm parsing the body of an http request that is set up in like this:

<something>
...
<inner_something> 
...
<foo bar='VALUE_I_WANT'>
... 
</FOO >
...
</inner_something>
...
</something>

What is an idiomatic approach to finding VALUE_I_WANT? Can I loop though the tokens using a decoder? How can check that a token is foo and get the attribute bar? (those names are constant). Is that the only way using the std lib? No way to look up tokens directly?

Answer 1

You can use the encoding/xml package to parse your data. For example, define types representing your XML data:

type Something struct {
    InnerSomething struct {
        Foo struct {
            Bar string `xml:"bar,attr"`
        } `xml:"foo"`
    } `xml:"inner_something"`
} 

type Result struct {
    Something `xml:"something"`
}

Then parse the data:

func main() {
    data := `
<something>
    <inner_something>
        <foo bar='VALUE_I_WANT'>test
        </foo >
    </inner_something>
</something>`
    v := Result{}
    err := xml.Unmarshal([]byte(data), &v)
    if err != nil {
        fmt.Printf("error: %v", err)
        return
    }
    fmt.Printf("bar: %q", v.Something.InnerSomething.Foo.Bar)
}

See https://golang.org/pkg/encoding/xml/.

Here is a working sample in the Go Playground.