Trait async_xml::reader::Visitor

pub trait Visitor<B: AsyncBufRead + Unpin> {
    type Output;

    fn build(self) -> Result<Self::Output, Error>;

    fn start_name() -> Option<&'static str> { ... }
    fn visit_tag(&mut self, name: &str) -> Result<(), Error> { ... }
    fn visit_attribute(&mut self, name: &str, value: &str) -> Result<(), Error> { ... }
    fn visit_child<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 mut self,
        name: &'life1 str,
        reader: &'life2 mut PeekingReader<B>
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + 'async_trait>>
   where
        'life0: 'async_trait,
        'life1: 'async_trait,
        'life2: 'async_trait,
        Self: 'async_trait,
    { ... }
    fn visit_text(&mut self, text: &str) -> Result<(), Error> { ... }
}

A trait for building up instances of types during deserialization

As XmlReader::read_event_into_async() does not return a Send future, this entire trait must be ?Send.

Required Associated Types

type Output

Output type this Visitor returns

Required Methods

fn build(self) -> Result<Self::Output, Error>

Validate and build the output type

Provided Methods

fn start_name() -> Option<&'static str>

Should return the expected starting tag name, if any

fn visit_tag(&mut self, name: &str) -> Result<(), Error>

Visit the starting tag with the given name

This is called exactly once during deserialization and will be called before any other visit_* methods.

fn visit_attribute(&mut self, name: &str, value: &str) -> Result<(), Error>

Visit an attribute with the given name and value

fn visit_child<'life0, 'life1, 'life2, 'async_trait>(
    &'life0 mut self,
    name: &'life1 str,
    reader: &'life2 mut PeekingReader<B>
) -> Pin<Box<dyn Future<Output = Result<(), Error>> + 'async_trait>>where
    'life0: 'async_trait,
    'life1: 'async_trait,
    'life2: 'async_trait,
    Self: 'async_trait,

Visit a child element with the given tag name

Implementations must make sure the child element is read in some way. Most likely this will be either a reader.skip_element() or reader.deserialize() call.

fn visit_text(&mut self, text: &str) -> Result<(), Error>

Visit any plain text contained in the element

May be called multiple times.

Implementors

impl<B> Visitor<B> for XmlNodewhere
    B: AsyncBufRead + Unpin,

type Output = XmlNode

impl<B, T> Visitor<B> for OptionalVisitor<T, B>where
    B: AsyncBufRead + Unpin,
    T: FromXml<B>,

type Output = Option<T>

impl<B, T, E> Visitor<B> for FromStringVisitor<T>where
    B: AsyncBufRead + Unpin,
    T: XmlFromStr + FromStr<Err = E>,
    E: Display,

type Output = T

impl<B, Target, FromType> Visitor<B> for FromVisitor<B, Target, FromType>where
    B: AsyncBufRead + Unpin,
    Target: From<FromType>,
    FromType: FromXml<B>,

type Output = Target

impl<B, Target, FromType, E> Visitor<B> for TryFromVisitor<B, Target, FromType, E>where
    B: AsyncBufRead + Unpin,
    Target: TryFrom<FromType, Error = E>,
    FromType: FromXml<B>,
    E: Display,

type Output = Target