deltachat/imap/
session.rs

1use std::collections::BTreeMap;
2use std::ops::{Deref, DerefMut};
3
4use anyhow::{Context as _, Result};
5use async_imap::Session as ImapSession;
6use async_imap::types::Mailbox;
7use futures::TryStreamExt;
8
9use crate::imap::capabilities::Capabilities;
10use crate::net::session::SessionStream;
11
12/// Prefetch:
13/// - Message-ID to check if we already have the message.
14/// - In-Reply-To and References to check if message is a reply to chat message.
15/// - Chat-Version to check if a message is a chat message
16/// - Autocrypt-Setup-Message to check if a message is an autocrypt setup message,
17///   not necessarily sent by Delta Chat.
18/// - Chat-Is-Post-Message to skip it in background fetch or when it is > `DownloadLimit`.
19const PREFETCH_FLAGS: &str = "(UID INTERNALDATE RFC822.SIZE BODY.PEEK[HEADER.FIELDS (\
20                              MESSAGE-ID \
21                              DATE \
22                              X-MICROSOFT-ORIGINAL-MESSAGE-ID \
23                              FROM \
24                              IN-REPLY-TO REFERENCES \
25                              CHAT-VERSION \
26                              CHAT-IS-POST-MESSAGE \
27                              AUTO-SUBMITTED \
28                              AUTOCRYPT-SETUP-MESSAGE\
29                              )])";
30
31#[derive(Debug)]
32pub(crate) struct Session {
33    transport_id: u32,
34
35    pub(super) inner: ImapSession<Box<dyn SessionStream>>,
36
37    pub capabilities: Capabilities,
38
39    /// Selected folder name.
40    pub selected_folder: Option<String>,
41
42    /// Mailbox structure returned by IMAP server.
43    pub selected_mailbox: Option<Mailbox>,
44
45    pub selected_folder_needs_expunge: bool,
46
47    /// True if currently selected folder has new messages.
48    ///
49    /// Should be false if no folder is currently selected.
50    pub new_mail: bool,
51
52    pub resync_request_sender: async_channel::Sender<()>,
53}
54
55impl Deref for Session {
56    type Target = ImapSession<Box<dyn SessionStream>>;
57
58    fn deref(&self) -> &Self::Target {
59        &self.inner
60    }
61}
62
63impl DerefMut for Session {
64    fn deref_mut(&mut self) -> &mut Self::Target {
65        &mut self.inner
66    }
67}
68
69impl Session {
70    pub(crate) fn new(
71        inner: ImapSession<Box<dyn SessionStream>>,
72        capabilities: Capabilities,
73        resync_request_sender: async_channel::Sender<()>,
74        transport_id: u32,
75    ) -> Self {
76        Self {
77            transport_id,
78            inner,
79            capabilities,
80            selected_folder: None,
81            selected_mailbox: None,
82            selected_folder_needs_expunge: false,
83            new_mail: false,
84            resync_request_sender,
85        }
86    }
87
88    /// Returns ID of the transport for which this session was created.
89    pub(crate) fn transport_id(&self) -> u32 {
90        self.transport_id
91    }
92
93    pub fn can_idle(&self) -> bool {
94        self.capabilities.can_idle
95    }
96
97    pub fn can_move(&self) -> bool {
98        self.capabilities.can_move
99    }
100
101    pub fn can_check_quota(&self) -> bool {
102        self.capabilities.can_check_quota
103    }
104
105    pub fn can_condstore(&self) -> bool {
106        self.capabilities.can_condstore
107    }
108
109    pub fn can_metadata(&self) -> bool {
110        self.capabilities.can_metadata
111    }
112
113    pub fn can_push(&self) -> bool {
114        self.capabilities.can_push
115    }
116
117    // Returns true if IMAP server has `XCHATMAIL` capability.
118    pub fn is_chatmail(&self) -> bool {
119        self.capabilities.is_chatmail
120    }
121
122    /// Returns the names of all folders on the IMAP server.
123    pub async fn list_folders(&mut self) -> Result<Vec<async_imap::types::Name>> {
124        let list = self.list(Some(""), Some("*")).await?.try_collect().await?;
125        Ok(list)
126    }
127
128    /// Prefetch `n_uids` messages starting from `uid_next`. Returns a list of fetch results in the
129    /// order of ascending delivery time to the server (INTERNALDATE).
130    pub(crate) async fn prefetch(
131        &mut self,
132        uid_next: u32,
133        n_uids: u32,
134    ) -> Result<Vec<(u32, async_imap::types::Fetch)>> {
135        let uid_last = uid_next.saturating_add(n_uids - 1);
136        // fetch messages with larger UID than the last one seen
137        let set = format!("{uid_next}:{uid_last}");
138        let mut list = self
139            .uid_fetch(set, PREFETCH_FLAGS)
140            .await
141            .context("IMAP could not fetch")?;
142
143        let mut msgs = BTreeMap::new();
144        while let Some(msg) = list.try_next().await? {
145            if let Some(msg_uid) = msg.uid {
146                msgs.insert((msg.internal_date(), msg_uid), msg);
147            }
148        }
149
150        Ok(msgs.into_iter().map(|((_, uid), msg)| (uid, msg)).collect())
151    }
152}
deltachat/imap/session.rs

deltachat/imap/
session.rs
