Re-wrote sync()

This commit is contained in:
daladim 2021-03-20 20:12:48 +01:00
parent 70557160f2
commit 54c6d510e8

View file

@ -58,13 +58,13 @@ where
/// Performs a synchronisation between `local` and `server`.
///
/// This bidirectional sync applies additions/deleteions made on a source to the other source.
/// This bidirectional sync applies additions/deletions made on a source to the other source.
/// In case of conflicts (the same item has been modified on both ends since the last sync, `server` always wins)
pub async fn sync(&mut self) -> Result<(), Box<dyn Error>> {
let last_sync = self.local.get_last_sync();
log::info!("Starting a sync. Last sync was at {:?}", last_sync);
let cals_server = self.server.get_calendars().await?;
let cals_server = self.server.get_calendars().await?;
for (id, cal_server) in cals_server {
let mut cal_server = cal_server.lock().unwrap();
@ -77,56 +77,64 @@ where
};
let mut cal_local = cal_local.lock().unwrap();
// Pull remote changes from the server
let mut tasks_id_to_remove_from_local = match last_sync {
None => Vec::new(),
Some(_date) => cal_server.find_deletions_from(cal_local.get_item_ids())
.iter()
.map(|id| id.clone())
.collect()
};
let mut tasks_to_add_to_local = Vec::new();
let server_mod = cal_server.get_items_modified_since(last_sync, None);
for (new_id, new_item) in &server_mod {
if server_mod.contains_key(new_id) {
log::warn!("Conflict for task {} ({}). Using the server version.", new_item.name(), new_id);
tasks_id_to_remove_from_local.push(new_id.clone());
}
tasks_to_add_to_local.push((*new_item).clone());
}
// Even in case of conflicts, "the server always wins", so it is safe to remove tasks from the local cache as soon as now
remove_from_calendar(&tasks_id_to_remove_from_local, &mut *cal_local);
// Push local changes to the server
let local_del = match last_sync {
Some(date) => cal_local.get_items_deleted_since(date),
// Step 1 - "Server always wins", so a delteion from the server must be applied locally, even if it was locally modified.
let mut local_dels = match last_sync {
None => HashSet::new(),
Some(date) => cal_local.get_items_deleted_since(date),
};
let mut tasks_id_to_remove_from_server = Vec::new();
for deleted_id in local_del {
if server_mod.contains_key(&deleted_id) {
log::warn!("Conflict for task {}, that has been locally deleted and updated in the server. Using the server version.", deleted_id);
continue;
if last_sync.is_some() {
let server_deletions = cal_server.find_deletions_from(cal_local.get_item_ids());
for server_del_id in server_deletions {
// Even in case of conflicts, "the server always wins", so it is safe to remove tasks from the local cache as soon as now
if let Err(err) = cal_local.delete_item(&server_del_id) {
log::error!("Unable to remove local item {}: {}", server_del_id, err);
}
if local_dels.contains(&server_del_id) {
local_dels.remove(&server_del_id);
}
tasks_id_to_remove_from_server.push(deleted_id);
}
}
let local_mod = cal_local.get_items_modified_since(last_sync, None);
let mut tasks_to_add_to_server = Vec::new();
for (new_id, new_item) in &local_mod {
if server_mod.contains_key(new_id) {
log::warn!("Conflict for task {} ({}). Using the server version.", new_item.name(), new_id);
continue;
// Step 2 - Compare both changesets...
let server_mods = cal_server.get_items_modified_since(last_sync, None);
let mut local_mods = cal_local.get_items_modified_since(last_sync, None);
// ...import remote changes,...
let mut conflicting_tasks = Vec::new();
let mut tasks_to_add = Vec::new();
for (server_mod_id, server_mod) in server_mods {
if local_mods.contains_key(&server_mod_id) {
log::warn!("Conflict for task {} (modified in both sources). Using the server version", server_mod_id);
conflicting_tasks.push(server_mod_id.clone());
local_mods.remove(&server_mod_id);
}
tasks_to_add_to_server.push((*new_item).clone());
if local_dels.contains(&server_mod_id) {
log::warn!("Conflict for task {} (modified in the server, deleted locally). Reverting to the server version", server_mod_id);
local_dels.remove(&server_mod_id);
}
tasks_to_add.push(server_mod.clone());
}
remove_from_calendar(&tasks_id_to_remove_from_server, &mut *cal_server);
move_to_calendar(&mut tasks_to_add_to_local, &mut *cal_local);
move_to_calendar(&mut tasks_to_add_to_server, &mut *cal_server);
// ...upload local deletions,...
for local_del_id in local_dels {
if let Err(err) = cal_server.delete_item(&local_del_id) {
log::error!("Unable to remove remote item {}: {}", local_del_id, err);
}
}
// ...and upload local changes
for (local_mod_id, local_mod) in local_mods {
// Conflicts are no longer in local_mods
if let Err(err) = cal_server.delete_item(&local_mod_id) {
log::error!("Unable to remove remote item (before an update) {}: {}", local_mod_id, err);
}
// TODO: should I add a .update_item()?
cal_server.add_item(local_mod.clone());
}
remove_from_calendar(&conflicting_tasks, &mut (*cal_local));
move_to_calendar(&mut tasks_to_add, &mut (*cal_local));
}
self.local.update_last_sync(None);
@ -139,13 +147,14 @@ where
fn move_to_calendar<C: PartialCalendar>(items: &mut Vec<Item>, calendar: &mut C) {
while items.len() > 0 {
let item = items.remove(0);
log::warn!("Moving {} to calendar", item.name());
calendar.add_item(item);
}
}
fn remove_from_calendar<C: PartialCalendar>(ids: &Vec<ItemId>, calendar: &mut C) {
for id in ids {
log::info!(" Removing {:?} from local calendar", id);
log::info!(" Removing {:?} from calendar", id);
if let Err(err) = calendar.delete_item(id) {
log::warn!("Unable to delete item {:?} from calendar: {}", id, err);
}