Struct Context 

pub struct Context<C> { /* private fields */ }

A request being crawled, with everything needed to handle it.

It holds the Request, a client to fetch it with, a Queue to add the links it leads to, and the crawl’s datasets. Handlers borrow it, so several of them can handle one request: the request is fetched once, by the first response or body, and the response’s head is kept. The body is always read from the client, so a browser page reads as currently rendered.

Implementations

impl<C> Context<C>

pub fn new(request: Request, client: C) -> Self

Creates a standalone context, e.g. to test a handler.

It gets an empty queue of its own and no datasets; see with_queue and with_dataset.

pub fn with_queue(self, queue: &Queue) -> Self

Replaces the queue, binding it to the request.

pub fn with_dataset<T, D>(self, dataset: D) -> Self

where T: Send + 'static, D: Dataset<T>,

Registers dataset for items of type T.

pub const fn request(&self) -> &Request

Returns the request.

pub const fn request_mut(&mut self) -> &mut Request

Returns the request mutably, e.g. to add headers before fetching.

pub const fn client(&self) -> &C

Returns the client.

pub const fn queue(&self) -> &Queue

Returns the queue for the links this request leads to.

pub fn dataset<T: Send + 'static>(&self) -> Result<Data<T>>

Returns the dataset for items of type T.

Errors

Returns a Dataset error if no dataset is registered for T.

pub async fn response(&self) -> Result<&Response<()>>

where C: Client,

Returns the response’s head, fetching the request on the first call.

Later calls return the same head without fetching again. A failed fetch is not kept: the next call tries again. Once fetched, links followed through the queue, including clones taken earlier, resolve against the URI the response was served from.

Errors

Returns an error if the client fails to fetch the request.

pub async fn body(&self) -> Result<Bytes>

where C: Client,

Returns the response’s body, fetching the request first if needed: the bytes received, or a browser page as currently rendered.

Errors

Returns an error if the request cannot be fetched or its body read.

Trait Implementations

impl<C> Debug for Context<C>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.