platform_data/
links.rs

1use crate::{Flow, LinksConstants};
2use platform_num::LinkReference;
3use std::{borrow::Cow, error, io};
4
5#[derive(thiserror::Error, Debug)]
6pub enum Error<'a, T: LinkReference> {
7    #[error("link {0} does not exist.")]
8    NotExists(T),
9
10    #[error("link {0:?} has dependencies")]
11    HasUsages(Vec<Cow<'a, [T]>>),
12
13    #[error("link {0} already exists")]
14    AlreadyExists(Cow<'a, T>),
15
16    #[error("limit for the number of links in the storage has been reached: {0}")]
17    LimitReached(T),
18
19    #[error("unable to allocate memory for links storage: `{0}`")]
20    AllocFailed(#[from] io::Error),
21
22    #[error("other internal error: `{0}`")]
23    Other(#[from] Box<dyn error::Error + Sync + Send>),
24}
25
26pub type ReadHandler<'a, T> = &'a mut dyn FnMut(&[T]) -> Flow;
27
28pub type WriteHandler<'a, T> = &'a mut dyn FnMut(&[T], &[T]) -> Flow;
29
30pub trait Links<T: LinkReference> {
31    fn constants_links(&self) -> LinksConstants<T>;
32
33    fn count_links(&self, query: &[T]) -> T;
34
35    fn create_links(
36        &mut self,
37        query: &[T],
38        handler: WriteHandler<'_, T>,
39    ) -> Result<Flow, Error<'_, T>>;
40
41    fn each_links(&self, query: &[T], handler: ReadHandler<'_, T>) -> Result<Flow, Error<'_, T>>;
42
43    fn update_links(
44        &mut self,
45        query: &[T],
46        replacement: &[T],
47        handler: WriteHandler<'_, T>,
48    ) -> Result<Flow, Error<'_, T>>;
49
50    fn delete_links(
51        &mut self,
52        query: &[T],
53        handler: WriteHandler<'_, T>,
54    ) -> Result<Flow, Error<'_, T>>;
55}
platform_data/links.rs

platform_data/
links.rs
