kitchen-freezer/src/traits.rs
2021-12-19 18:50:00 +01:00

134 lines
5.7 KiB
Rust

//! Traits used by multiple structs in this crate
use std::error::Error;
use std::collections::{HashMap, HashSet};
use std::sync::{Arc, Mutex};
use async_trait::async_trait;
use csscolorparser::Color;
use url::Url;
use crate::item::SyncStatus;
use crate::item::Item;
use crate::item::VersionTag;
use crate::calendar::SupportedComponents;
use crate::resource::Resource;
/// This trait must be implemented by data sources (either local caches or remote CalDAV clients)
///
/// Note that some concrete types (e.g. [`crate::cache::Cache`]) can also provide non-async versions of these functions
#[async_trait]
pub trait CalDavSource<T: BaseCalendar> {
/// Returns the current calendars that this source contains
/// This function may trigger an update (that can be a long process, or that can even fail, e.g. in case of a remote server)
async fn get_calendars(&self) -> Result<HashMap<Url, Arc<Mutex<T>>>, Box<dyn Error>>;
/// Returns the calendar matching the URL
async fn get_calendar(&self, url: &Url) -> Option<Arc<Mutex<T>>>;
/// Create a calendar if it did not exist, and return it
async fn create_calendar(&mut self, url: Url, name: String, supported_components: SupportedComponents, color: Option<Color>)
-> Result<Arc<Mutex<T>>, Box<dyn Error>>;
// Removing a calendar is not supported yet
}
/// This trait contains functions that are common to all calendars
///
/// Note that some concrete types (e.g. [`crate::calendar::cached_calendar::CachedCalendar`]) can also provide non-async versions of these functions
#[async_trait]
pub trait BaseCalendar {
/// Returns the calendar name
fn name(&self) -> &str;
/// Returns the calendar URL
fn url(&self) -> &Url;
/// Returns the supported kinds of components for this calendar
fn supported_components(&self) -> crate::calendar::SupportedComponents;
/// Returns the user-defined color of this calendar
fn color(&self) -> Option<&Color>;
/// Add an item into this calendar, and return its new sync status.
/// For local calendars, the sync status is not modified.
/// For remote calendars, the sync status is updated by the server
async fn add_item(&mut self, item: Item) -> Result<SyncStatus, Box<dyn Error>>;
/// Update an item that already exists in this calendar and returns its new `SyncStatus`
/// This replaces a given item at a given URL
async fn update_item(&mut self, item: Item) -> Result<SyncStatus, Box<dyn Error>>;
/// Returns whether this calDAV calendar supports to-do items
fn supports_todo(&self) -> bool {
self.supported_components().contains(crate::calendar::SupportedComponents::TODO)
}
/// Returns whether this calDAV calendar supports calendar items
fn supports_events(&self) -> bool {
self.supported_components().contains(crate::calendar::SupportedComponents::EVENT)
}
}
/// Functions availabe for calendars that are backed by a CalDAV server
///
/// Note that some concrete types (e.g. [`crate::calendar::cached_calendar::CachedCalendar`]) can also provide non-async versions of these functions
#[async_trait]
pub trait DavCalendar : BaseCalendar {
/// Create a new calendar
fn new(name: String, resource: Resource, supported_components: SupportedComponents, color: Option<Color>) -> Self;
/// Get the URLs and the version tags of every item in this calendar
async fn get_item_version_tags(&self) -> Result<HashMap<Url, VersionTag>, Box<dyn Error>>;
/// Returns a particular item
async fn get_item_by_url(&self, url: &Url) -> Result<Option<Item>, Box<dyn Error>>;
/// Delete an item
async fn delete_item(&mut self, item_url: &Url) -> Result<(), Box<dyn Error>>;
/// Get the URLs of all current items in this calendar
async fn get_item_urls(&self) -> Result<HashSet<Url>, Box<dyn Error>> {
let items = self.get_item_version_tags().await?;
Ok(items.iter()
.map(|(url, _tag)| url.clone())
.collect())
}
// Note: the CalDAV protocol could also enable to do this:
// fn get_current_version(&self) -> CTag
}
/// Functions availabe for calendars we have full knowledge of
///
/// Usually, these are local calendars fully backed by a local folder
///
/// Note that some concrete types (e.g. [`crate::calendar::cached_calendar::CachedCalendar`]) can also provide non-async versions of these functions
#[async_trait]
pub trait CompleteCalendar : BaseCalendar {
/// Create a new calendar
fn new(name: String, url: Url, supported_components: SupportedComponents, color: Option<Color>) -> Self;
/// Get the URLs of all current items in this calendar
async fn get_item_urls(&self) -> Result<HashSet<Url>, Box<dyn Error>>;
/// Returns all items that this calendar contains
async fn get_items(&self) -> Result<HashMap<Url, &Item>, Box<dyn Error>>;
/// Returns all items that this calendar contains
async fn get_items_mut(&mut self) -> Result<HashMap<Url, &mut Item>, Box<dyn Error>>;
/// Returns a particular item
async fn get_item_by_url<'a>(&'a self, url: &Url) -> Option<&'a Item>;
/// Returns a particular item
async fn get_item_by_url_mut<'a>(&'a mut self, url: &Url) -> Option<&'a mut Item>;
/// Mark an item for deletion.
/// This is required so that the upcoming sync will know it should also also delete this task from the server
/// (and then call [`CompleteCalendar::immediately_delete_item`] once it has been successfully deleted on the server)
async fn mark_for_deletion(&mut self, item_id: &Url) -> Result<(), Box<dyn Error>>;
/// Immediately remove an item. See [`CompleteCalendar::mark_for_deletion`]
async fn immediately_delete_item(&mut self, item_id: &Url) -> Result<(), Box<dyn Error>>;
}