mastodon API rust lib elefren, fixed and updated. and also all ASYNC! NB. most examples are now wrong.
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
elefren-fork/src/page.rs

126 lines
3.5 KiB

use super::{deserialise, Mastodon, Result};
use entities::itemsiter::ItemsIter;
use reqwest::{
header::{Link, RelationType},
Response,
};
use serde::Deserialize;
use url::Url;
use http_send::HttpSend;
/// Represents a single page of API results
#[derive(Debug, Clone)]
pub struct Page<'a, T: for<'de> Deserialize<'de>, H: 'a + HttpSend> {
mastodon: &'a Mastodon<H>,
next: Option<Url>,
prev: Option<Url>,
/// Initial set of items
pub initial_items: Vec<T>,
}
macro_rules! pages {
($($direction:ident: $fun:ident),*) => {
$(
doc_comment!(concat!(
"Method to retrieve the ", stringify!($direction), " page of results"),
pub fn $fun(&mut self) -> Result<Option<Vec<T>>> {
let url = match self.$direction.take() {
Some(s) => s,
None => return Ok(None),
};
let response = self.mastodon.send(
&mut self.mastodon.client.get(url)
)?;
let (prev, next) = get_links(&response)?;
self.next = next;
self.prev = prev;
deserialise(response)
});
)*
}
}
impl<'a, T: for<'de> Deserialize<'de>, H: HttpSend> Page<'a, T, H> {
pages! {
next: next_page,
prev: prev_page
}
pub(crate) fn new(mastodon: &'a Mastodon<H>, response: Response) -> Result<Self> {
let (prev, next) = get_links(&response)?;
Ok(Page {
initial_items: deserialise(response)?,
next,
prev,
mastodon,
})
}
}
impl<'a, T: Clone + for<'de> Deserialize<'de>, H: HttpSend> Page<'a, T, H> {
/// Returns an iterator that provides a stream of `T`s
///
/// This abstracts away the process of iterating over each item in a page,
/// then making an http call, then iterating over each item in the new
/// page, etc. The iterator provides a stream of `T`s, calling
/// `self.next_page()`
/// when necessary to get
/// more of them, until
/// there are no more items.
///
/// # Example
///
/// ```no_run
/// # extern crate elefren;
/// # use std::error::Error;
/// use elefren::prelude::*;
/// # fn main() -> Result<(), Box<Error>> {
/// # let data = Data {
/// # base: "".into(),
/// # client_id: "".into(),
/// # client_secret: "".into(),
/// # redirect: "".into(),
/// # token: "".into(),
/// # };
/// let mastodon = Mastodon::from(data);
/// let req = StatusesRequest::new();
/// let resp = mastodon.statuses("some-id", req)?;
/// for status in resp.items_iter() {
/// // do something with status
/// }
/// # Ok(())
/// # }
/// ```
pub fn items_iter(self) -> impl Iterator<Item = T> + 'a
where
T: 'a,
{
ItemsIter::new(self)
}
}
fn get_links(response: &Response) -> Result<(Option<Url>, Option<Url>)> {
let mut prev = None;
let mut next = None;
if let Some(link_header) = response.headers().get::<Link>() {
for value in link_header.values() {
if let Some(relations) = value.rel() {
if relations.contains(&RelationType::Next) {
next = Some(Url::parse(value.link())?);
}
if relations.contains(&RelationType::Prev) {
prev = Some(Url::parse(value.link())?);
}
}
}
}
Ok((prev, next))
}