Elementary data structure for mailbox list

This commit is contained in:
Alex 2022-06-30 13:33:58 +02:00
parent 0f0a8d415e
commit 89b5883387
Signed by: lx
GPG key ID: 0E496D15096376BE
2 changed files with 139 additions and 39 deletions

View file

@ -22,13 +22,18 @@ pub struct Mailbox {
}
impl Mailbox {
pub(super) async fn open(creds: &Credentials, id: UniqueIdent) -> Result<Self> {
pub(super) async fn open(creds: &Credentials, id: UniqueIdent, min_uidvalidity: ImapUidvalidity) -> Result<Self> {
let index_path = format!("index/{}", id);
let mail_path = format!("mail/{}", id);
let mut uid_index = Bayou::<UidIndex>::new(creds, index_path)?;
uid_index.sync().await?;
let uidvalidity = uid_index.state().uidvalidity;
if uidvalidity < min_uidvalidity {
uid_index.push(uid_index.state().op_bump_uidvalidity(min_uidvalidity.get() - uidvalidity.get())).await?;
}
let mbox = RwLock::new(MailboxInternal {
id,
bucket: creds.bucket().to_string(),

View file

@ -1,66 +1,60 @@
use std::collections::HashMap;
use std::collections::{HashMap, BTreeMap};
use std::sync::{Arc, Weak};
use anyhow::Result;
use anyhow::{Result, bail};
use lazy_static::lazy_static;
use serde::{Serialize, Deserialize};
use k2v_client::{K2vClient, CausalityToken, K2vValue};
use k2v_client::K2vClient;
use rusoto_s3::S3Client;
use crate::cryptoblob::{seal_serialize, open_deserialize};
use crate::login::{Credentials, StorageCredentials};
use crate::mail::mailbox::Mailbox;
use crate::mail::unique_ident::UniqueIdent;
use crate::mail::unique_ident::{UniqueIdent, gen_ident};
use crate::mail::uidindex::ImapUidvalidity;
use crate::time::now_msec;
const MAILBOX_HIERARCHY_DELIMITER: &str = "/";
/// INBOX is the only mailbox that must always exist.
/// It is created automatically when the account is created.
/// IMAP allows the user to rename INBOX to something else,
/// in this case all messages from INBOX are moved to a mailbox
/// with the new name and the INBOX mailbox still exists and is empty.
/// In our implementation, we indeed move the underlying mailbox
/// to the new name (i.e. the new name has the same id as the previous
/// INBOX), and we create a new empty mailbox for INBOX.
const INBOX: &str = "INBOX";
pub struct User {
pub username: String,
pub creds: Credentials,
pub s3_client: S3Client,
pub k2v_client: K2vClient,
pub k2v: K2vClient,
}
impl User {
pub fn new(username: String, creds: Credentials) -> Result<Self> {
let s3_client = creds.s3_client()?;
let k2v_client = creds.k2v_client()?;
let k2v = creds.k2v_client()?;
Ok(Self {
username,
creds,
s3_client,
k2v_client,
k2v,
})
}
/// Lists user's available mailboxes
pub fn list_mailboxes(&self) -> Result<Vec<String>> {
unimplemented!()
pub async fn list_mailboxes(&self) -> Result<Vec<String>> {
let (list, _ct) = self.load_mailbox_list().await?;
Ok(list.into_iter().map(|(k, _)| k).collect())
}
/// Opens an existing mailbox given its IMAP name.
pub async fn open_mailbox(&self, name: &str) -> Result<Option<Arc<Mailbox>>> {
// TODO: handle mailbox names, mappings, renaming, etc
let id = match name {
"INBOX" => UniqueIdent([0u8; 24]),
_ => panic!("Only INBOX exists for now"),
};
let cache_key = (self.creds.storage.clone(), id);
{
let cache = MAILBOX_CACHE.cache.lock().unwrap();
if let Some(mb) = cache.get(&cache_key).and_then(Weak::upgrade) {
return Ok(Some(mb));
}
}
let mb = Arc::new(Mailbox::open(&self.creds, id).await?);
let mut cache = MAILBOX_CACHE.cache.lock().unwrap();
if let Some(concurrent_mb) = cache.get(&cache_key).and_then(Weak::upgrade) {
drop(mb); // we worked for nothing but at least we didn't starve someone else
Ok(Some(concurrent_mb))
} else {
cache.insert(cache_key, Arc::downgrade(&mb));
Ok(Some(mb))
let (list, _ct) = self.load_mailbox_list().await?;
match list.get(name) {
Some(MailboxListEntry { id_lww: (_, Some(mbid)), uidvalidity }) =>
self.open_mailbox_by_id(*mbid, *uidvalidity).await,
_ =>
bail!("Mailbox does not exist: {}", name),
}
}
@ -78,6 +72,107 @@ impl User {
pub fn rename_mailbox(&self, _old_name: &str, _new_name: &str) -> Result<()> {
unimplemented!()
}
// ---- Internal mailbox management ----
async fn open_mailbox_by_id(&self, id: UniqueIdent, min_uidvalidity: ImapUidvalidity) -> Result<Option<Arc<Mailbox>>> {
let cache_key = (self.creds.storage.clone(), id);
{
let cache = MAILBOX_CACHE.cache.lock().unwrap();
if let Some(mb) = cache.get(&cache_key).and_then(Weak::upgrade) {
return Ok(Some(mb));
}
}
let mb = Arc::new(Mailbox::open(&self.creds, id, min_uidvalidity).await?);
let mut cache = MAILBOX_CACHE.cache.lock().unwrap();
if let Some(concurrent_mb) = cache.get(&cache_key).and_then(Weak::upgrade) {
drop(mb); // we worked for nothing but at least we didn't starve someone else
Ok(Some(concurrent_mb))
} else {
cache.insert(cache_key, Arc::downgrade(&mb));
Ok(Some(mb))
}
}
// ---- Mailbox list management ----
async fn load_mailbox_list(&self) -> Result<(MailboxList, Option<CausalityToken>)> {
let cv = match self.k2v.read_item("mailboxes", "list").await {
Err(k2v_client::Error::NotFound) => return Ok((BTreeMap::new(), None)),
Err(e) => return Err(e.into()),
Ok(cv) => cv,
};
let mut list = BTreeMap::new();
for v in cv.value {
if let K2vValue::Value(vbytes) = v {
let list2 = open_deserialize::<MailboxList>(&vbytes, &self.creds.keys.master)?;
list = merge_mailbox_lists(list, list2);
}
}
// If INBOX doesn't exist, create a new mailbox with that name
// and save new mailbox list.
match list.get_mut(INBOX) {
None => {
list.insert(INBOX.into(), MailboxListEntry {
id_lww: (now_msec(), Some(gen_ident())),
uidvalidity: ImapUidvalidity::new(1).unwrap(),
});
self.save_mailbox_list(&list, Some(cv.causality.clone())).await?;
}
Some(MailboxListEntry { id_lww, uidvalidity }) if id_lww.1.is_none() => {
id_lww.0 = std::cmp::max(id_lww.0 + 1, now_msec());
id_lww.1 = Some(gen_ident());
*uidvalidity = ImapUidvalidity::new(uidvalidity.get() + 1).unwrap();
self.save_mailbox_list(&list, Some(cv.causality.clone())).await?;
}
_ => (),
}
Ok((list, Some(cv.causality)))
}
async fn save_mailbox_list(&self, list: &MailboxList, ct: Option<CausalityToken>) -> Result<()> {
let list_blob = seal_serialize(list, &self.creds.keys.master)?;
self.k2v.insert_item("mailboxes", "list", list_blob, ct).await?;
Ok(())
}
}
// ---- User's mailbox list (serialized in K2V) ----
type MailboxList = BTreeMap<String, MailboxListEntry>;
#[derive(Serialize, Deserialize, Clone, Copy)]
struct MailboxListEntry {
id_lww: (u64, Option<UniqueIdent>),
uidvalidity: ImapUidvalidity,
}
impl MailboxListEntry {
fn merge(&mut self, other: &Self) {
// Simple CRDT merge rule
if other.id_lww.0 > self.id_lww.0
|| (other.id_lww.0 == self.id_lww.0 && other.id_lww.1 > self.id_lww.1) {
self.id_lww = other.id_lww;
}
self.uidvalidity = std::cmp::max(self.uidvalidity, other.uidvalidity);
}
}
fn merge_mailbox_lists(mut list1: MailboxList, list2: MailboxList) -> MailboxList {
for (k, v) in list2.into_iter() {
if let Some(e) = list1.get_mut(&k) {
e.merge(&v);
} else {
list1.insert(k, v);
}
}
list1
}
// ---- Mailbox cache ----