meli/melib/src/backends.rs
2020-07-06 15:27:08 +03:00

653 lines
18 KiB
Rust

/*
* meli - backends module
*
* Copyright 2017 Manos Pitsidianakis
*
* This file is part of meli.
*
* meli is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* meli is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with meli. If not, see <http://www.gnu.org/licenses/>.
*/
use smallvec::SmallVec;
#[macro_export]
macro_rules! tag_hash {
($tag:ident) => {{
use std::collections::hash_map::DefaultHasher;
use std::hash::Hasher;
let mut hasher = DefaultHasher::new();
hasher.write($tag.as_bytes());
hasher.finish()
}};
}
#[cfg(feature = "imap_backend")]
pub mod imap;
#[cfg(feature = "notmuch_backend")]
pub mod notmuch;
#[cfg(feature = "notmuch_backend")]
pub use self::notmuch::NotmuchDb;
#[cfg(feature = "jmap_backend")]
pub mod jmap;
#[cfg(feature = "maildir_backend")]
pub mod maildir;
#[cfg(feature = "mbox_backend")]
pub mod mbox;
#[cfg(feature = "imap_backend")]
pub use self::imap::ImapType;
#[cfg(feature = "jmap_backend")]
pub use self::jmap::JmapType;
use crate::async_workers::*;
use crate::conf::AccountSettings;
use crate::error::{MeliError, Result};
#[cfg(feature = "maildir_backend")]
use self::maildir::MaildirType;
#[cfg(feature = "mbox_backend")]
use self::mbox::MboxType;
use super::email::{Envelope, EnvelopeHash, Flag};
use std::any::Any;
use std::collections::BTreeMap;
use std::fmt;
use std::fmt::Debug;
use std::ops::Deref;
use std::sync::{Arc, RwLock};
pub use futures::stream::Stream;
use std::future::Future;
pub use std::pin::Pin;
use std::collections::HashMap;
#[macro_export]
macro_rules! get_path_hash {
($path:expr) => {{
use std::collections::hash_map::DefaultHasher;
use std::hash::{Hash, Hasher};
let mut hasher = DefaultHasher::new();
$path.hash(&mut hasher);
hasher.finish()
}};
}
pub type BackendCreator = Box<
dyn Fn(
&AccountSettings,
Box<dyn Fn(&str) -> bool + Send + Sync>,
) -> Result<Box<dyn MailBackend>>,
>;
/// A hashmap containing all available mail backends.
/// An abstraction over any available backends.
pub struct Backends {
map: HashMap<std::string::String, Backend>,
}
pub struct Backend {
pub create_fn: Box<dyn Fn() -> BackendCreator>,
pub validate_conf_fn: Box<dyn Fn(&AccountSettings) -> Result<()>>,
}
impl Default for Backends {
fn default() -> Self {
Backends::new()
}
}
#[cfg(feature = "notmuch_backend")]
pub const NOTMUCH_ERROR_MSG: &str =
"libnotmuch5 was not found in your system. Make sure it is installed and in the library paths.\n";
#[cfg(not(feature = "notmuch_backend"))]
pub const NOTMUCH_ERROR_MSG: &str = "this version of meli is not compiled with notmuch support. Use an appropriate version and make sure libnotmuch5 is installed and in the library paths.\n";
impl Backends {
pub fn new() -> Self {
let mut b = Backends {
map: HashMap::with_capacity_and_hasher(1, Default::default()),
};
#[cfg(feature = "maildir_backend")]
{
b.register(
"maildir".to_string(),
Backend {
create_fn: Box::new(|| Box::new(|f, i| MaildirType::new(f, i))),
validate_conf_fn: Box::new(MaildirType::validate_config),
},
);
}
#[cfg(feature = "mbox_backend")]
{
b.register(
"mbox".to_string(),
Backend {
create_fn: Box::new(|| Box::new(|f, i| MboxType::new(f, i))),
validate_conf_fn: Box::new(MboxType::validate_config),
},
);
}
#[cfg(feature = "imap_backend")]
{
b.register(
"imap".to_string(),
Backend {
create_fn: Box::new(|| Box::new(|f, i| imap::ImapType::new(f, i))),
validate_conf_fn: Box::new(imap::ImapType::validate_config),
},
);
}
#[cfg(feature = "notmuch_backend")]
{
if libloading::Library::new("libnotmuch.so.5").is_ok() {
b.register(
"notmuch".to_string(),
Backend {
create_fn: Box::new(|| Box::new(|f, i| NotmuchDb::new(f, i))),
validate_conf_fn: Box::new(NotmuchDb::validate_config),
},
);
}
}
#[cfg(feature = "jmap_backend")]
{
b.register(
"jmap".to_string(),
Backend {
create_fn: Box::new(|| Box::new(|f, i| JmapType::new(f, i))),
validate_conf_fn: Box::new(JmapType::validate_config),
},
);
}
b
}
pub fn get(&self, key: &str) -> BackendCreator {
if !self.map.contains_key(key) {
if key == "notmuch" {
eprint!("{}", NOTMUCH_ERROR_MSG);
}
panic!("{} is not a valid mail backend", key);
}
(self.map[key].create_fn)()
}
pub fn register(&mut self, key: String, backend: Backend) {
if self.map.contains_key(&key) {
panic!("{} is an already registered backend", key);
}
self.map.insert(key, backend);
}
pub fn validate_config(&self, key: &str, s: &AccountSettings) -> Result<()> {
(self
.map
.get(key)
.ok_or_else(|| {
MeliError::new(format!(
"{}{} is not a valid mail backend",
if key == "notmuch" {
NOTMUCH_ERROR_MSG
} else {
""
},
key
))
})?
.validate_conf_fn)(s)
}
}
#[derive(Debug, Clone)]
pub enum RefreshEventKind {
Update(EnvelopeHash, Box<Envelope>),
/// Rename(old_hash, new_hash)
Rename(EnvelopeHash, EnvelopeHash),
Create(Box<Envelope>),
Remove(EnvelopeHash),
NewFlags(EnvelopeHash, (Flag, Vec<String>)),
Rescan,
Failure(MeliError),
}
#[derive(Debug, Clone)]
pub struct RefreshEvent {
mailbox_hash: MailboxHash,
account_hash: AccountHash,
kind: RefreshEventKind,
}
impl RefreshEvent {
pub fn mailbox_hash(&self) -> MailboxHash {
self.mailbox_hash
}
pub fn account_hash(&self) -> AccountHash {
self.account_hash
}
pub fn kind(self) -> RefreshEventKind {
/* consumes self! */
self.kind
}
}
/// A `RefreshEventConsumer` is a boxed closure that must be used to consume a `RefreshEvent` and
/// send it to a UI provided channel. We need this level of abstraction to provide an interface for
/// all users of mailbox refresh events.
pub struct RefreshEventConsumer(Box<dyn Fn(RefreshEvent) -> () + Send + Sync>);
impl RefreshEventConsumer {
pub fn new(b: Box<dyn Fn(RefreshEvent) -> () + Send + Sync>) -> Self {
RefreshEventConsumer(b)
}
pub fn send(&self, r: RefreshEvent) {
self.0(r);
}
}
impl fmt::Debug for RefreshEventConsumer {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "RefreshEventConsumer")
}
}
pub struct NotifyFn(Box<dyn Fn(MailboxHash) -> () + Send + Sync>);
impl fmt::Debug for NotifyFn {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "NotifyFn Box")
}
}
impl From<Box<dyn Fn(MailboxHash) -> () + Send + Sync>> for NotifyFn {
fn from(kind: Box<dyn Fn(MailboxHash) -> () + Send + Sync>) -> Self {
NotifyFn(kind)
}
}
impl NotifyFn {
pub fn new(b: Box<dyn Fn(MailboxHash) -> () + Send + Sync>) -> Self {
NotifyFn(b)
}
pub fn notify(&self, f: MailboxHash) {
self.0(f);
}
}
pub type ResultFuture<T> = Result<Pin<Box<dyn Future<Output = Result<T>> + Send + 'static>>>;
pub trait MailBackend: ::std::fmt::Debug + Send + Sync {
fn is_async(&self) -> bool;
fn is_remote(&self) -> bool;
fn is_online(&self) -> Result<()> {
Err(MeliError::new("Unimplemented."))
}
fn is_online_async(&self) -> ResultFuture<()> {
Err(MeliError::new("Unimplemented."))
}
fn get(&mut self, mailbox: &Mailbox) -> Result<Async<Result<Vec<Envelope>>>>;
fn get_async(
&mut self,
_mailbox: &Mailbox,
) -> Result<Pin<Box<dyn Stream<Item = Result<Vec<Envelope>>> + Send + 'static>>> {
Err(MeliError::new("Unimplemented."))
}
fn refresh(
&mut self,
_mailbox_hash: MailboxHash,
_sender: RefreshEventConsumer,
) -> Result<Async<()>> {
Err(MeliError::new("Unimplemented."))
}
fn refresh_async(
&mut self,
_mailbox_hash: MailboxHash,
_sender: RefreshEventConsumer,
) -> ResultFuture<()> {
Err(MeliError::new("Unimplemented."))
}
fn watch(
&self,
sender: RefreshEventConsumer,
work_context: WorkContext,
) -> Result<std::thread::ThreadId>;
fn watch_async(&self, _sender: RefreshEventConsumer) -> ResultFuture<()> {
Err(MeliError::new("Unimplemented."))
}
fn mailboxes(&self) -> Result<HashMap<MailboxHash, Mailbox>>;
fn mailboxes_async(&self) -> ResultFuture<HashMap<MailboxHash, Mailbox>> {
Err(MeliError::new("Unimplemented."))
}
fn operation(&self, hash: EnvelopeHash) -> Result<Box<dyn BackendOp>>;
fn save(
&self,
bytes: Vec<u8>,
mailbox_hash: MailboxHash,
flags: Option<Flag>,
) -> ResultFuture<()>;
fn delete(&self, _env_hash: EnvelopeHash, _mailbox_hash: MailboxHash) -> ResultFuture<()> {
Err(MeliError::new("Unimplemented."))
}
fn tags(&self) -> Option<Arc<RwLock<BTreeMap<u64, String>>>> {
None
}
fn as_any(&self) -> &dyn Any;
fn as_any_mut(&mut self) -> &mut dyn Any {
unimplemented!()
}
fn create_mailbox(
&mut self,
_path: String,
) -> ResultFuture<(MailboxHash, HashMap<MailboxHash, Mailbox>)> {
Err(MeliError::new("Unimplemented."))
}
fn delete_mailbox(
&mut self,
_mailbox_hash: MailboxHash,
) -> ResultFuture<HashMap<MailboxHash, Mailbox>> {
Err(MeliError::new("Unimplemented."))
}
fn set_mailbox_subscription(
&mut self,
_mailbox_hash: MailboxHash,
_val: bool,
) -> ResultFuture<()> {
Err(MeliError::new("Unimplemented."))
}
fn rename_mailbox(
&mut self,
_mailbox_hash: MailboxHash,
_new_path: String,
) -> ResultFuture<Mailbox> {
Err(MeliError::new("Unimplemented."))
}
fn set_mailbox_permissions(
&mut self,
_mailbox_hash: MailboxHash,
_val: MailboxPermissions,
) -> ResultFuture<()> {
Err(MeliError::new("Unimplemented."))
}
fn search(
&self,
_query: crate::search::Query,
_mailbox_hash: Option<MailboxHash>,
) -> ResultFuture<SmallVec<[EnvelopeHash; 512]>> {
Err(MeliError::new("Unimplemented."))
}
}
/// A `BackendOp` manages common operations for the various mail backends. They only live for the
/// duration of the operation. They are generated by the `operation` method of `Mailbackend` trait.
///
/// # Motivation
///
/// We need a way to do various operations on individual mails regardless of what backend they come
/// from (eg local or imap).
///
/// # Creation
/// ```ignore
/// /* Create operation from Backend */
///
/// let op = backend.operation(message.hash(), mailbox.hash());
/// ```
///
/// # Example
/// ```ignore
/// use melib::backends::{BackendOp};
/// use melib::Result;
/// use melib::{Envelope, Flag};
///
/// #[derive(Debug)]
/// struct FooOp {}
///
/// impl BackendOp for FooOp {
/// fn as_bytes(&mut self) -> Result<&[u8]> {
/// unimplemented!()
/// }
/// fn fetch_flags(&self) -> Result<Flag> {
/// unimplemented!()
/// }
/// }
///
/// let operation = Box::new(FooOp {});
/// ```
pub trait BackendOp: ::std::fmt::Debug + ::std::marker::Send {
fn as_bytes(&mut self) -> ResultFuture<Vec<u8>>;
fn copy_to(&self, _mailbox_hash: MailboxHash) -> ResultFuture<()> {
Err(MeliError::new("Unimplemented."))
}
fn fetch_flags(&self) -> ResultFuture<Flag>;
fn set_flag(&mut self, flag: Flag, value: bool) -> ResultFuture<()>;
fn set_tag(&mut self, tag: String, value: bool) -> ResultFuture<()>;
}
/// Wrapper for BackendOps that are to be set read-only.
///
/// Warning: Backend implementations may still cause side-effects (for example IMAP can set the
/// Seen flag when fetching an envelope)
#[derive(Debug)]
pub struct ReadOnlyOp {
op: Box<dyn BackendOp>,
}
impl ReadOnlyOp {
pub fn new(op: Box<dyn BackendOp>) -> Box<dyn BackendOp> {
Box::new(ReadOnlyOp { op })
}
}
impl BackendOp for ReadOnlyOp {
fn as_bytes(&mut self) -> ResultFuture<Vec<u8>> {
self.op.as_bytes()
}
fn fetch_flags(&self) -> ResultFuture<Flag> {
self.op.fetch_flags()
}
fn set_flag(&mut self, _flag: Flag, _value: bool) -> ResultFuture<()> {
Err(MeliError::new("read-only set."))
}
fn set_tag(&mut self, _tag: String, _value: bool) -> ResultFuture<()> {
Err(MeliError::new("read-only set."))
}
}
#[derive(Debug, Copy, Hash, Eq, Clone, Serialize, Deserialize, PartialEq)]
pub enum SpecialUsageMailbox {
Normal,
Inbox,
Archive,
Drafts,
Flagged,
Junk,
Sent,
Trash,
}
impl std::fmt::Display for SpecialUsageMailbox {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
use SpecialUsageMailbox::*;
write!(
f,
"{}",
match self {
Normal => "Normal",
Inbox => "Inbox",
Archive => "Archive",
Drafts => "Drafts",
Flagged => "Flagged",
Junk => "Junk",
Sent => "Sent",
Trash => "Trash",
}
)
}
}
impl Default for SpecialUsageMailbox {
fn default() -> Self {
SpecialUsageMailbox::Normal
}
}
impl SpecialUsageMailbox {
pub fn detect_usage(name: &str) -> Option<SpecialUsageMailbox> {
if name.eq_ignore_ascii_case("inbox") {
Some(SpecialUsageMailbox::Inbox)
} else if name.eq_ignore_ascii_case("archive") {
Some(SpecialUsageMailbox::Archive)
} else if name.eq_ignore_ascii_case("drafts") {
Some(SpecialUsageMailbox::Drafts)
} else if name.eq_ignore_ascii_case("junk") || name.eq_ignore_ascii_case("spam") {
Some(SpecialUsageMailbox::Junk)
} else if name.eq_ignore_ascii_case("sent") {
Some(SpecialUsageMailbox::Sent)
} else if name.eq_ignore_ascii_case("trash") {
Some(SpecialUsageMailbox::Trash)
} else {
Some(SpecialUsageMailbox::Normal)
}
}
}
pub trait BackendMailbox: Debug {
fn hash(&self) -> MailboxHash;
fn name(&self) -> &str;
/// Path of mailbox within the mailbox hierarchy, with `/` as separator.
fn path(&self) -> &str;
fn change_name(&mut self, new_name: &str);
fn clone(&self) -> Mailbox;
fn children(&self) -> &[MailboxHash];
fn parent(&self) -> Option<MailboxHash>;
fn is_subscribed(&self) -> bool;
fn set_is_subscribed(&mut self, new_val: bool) -> Result<()>;
fn set_special_usage(&mut self, new_val: SpecialUsageMailbox) -> Result<()>;
fn special_usage(&self) -> SpecialUsageMailbox;
fn permissions(&self) -> MailboxPermissions;
fn count(&self) -> Result<(usize, usize)>;
}
#[derive(Debug)]
struct DummyMailbox {
v: Vec<MailboxHash>,
}
impl BackendMailbox for DummyMailbox {
fn hash(&self) -> MailboxHash {
0
}
fn name(&self) -> &str {
""
}
fn path(&self) -> &str {
""
}
fn change_name(&mut self, _s: &str) {}
fn clone(&self) -> Mailbox {
mailbox_default()
}
fn special_usage(&self) -> SpecialUsageMailbox {
SpecialUsageMailbox::Normal
}
fn children(&self) -> &[MailboxHash] {
&self.v
}
fn parent(&self) -> Option<MailboxHash> {
None
}
fn permissions(&self) -> MailboxPermissions {
MailboxPermissions::default()
}
fn is_subscribed(&self) -> bool {
true
}
fn set_is_subscribed(&mut self, _new_val: bool) -> Result<()> {
Ok(())
}
fn set_special_usage(&mut self, _new_val: SpecialUsageMailbox) -> Result<()> {
Ok(())
}
fn count(&self) -> Result<(usize, usize)> {
Ok((0, 0))
}
}
pub fn mailbox_default() -> Mailbox {
Box::new(DummyMailbox {
v: Vec::with_capacity(0),
})
}
pub type AccountHash = u64;
pub type MailboxHash = u64;
pub type Mailbox = Box<dyn BackendMailbox + Send + Sync>;
impl Clone for Mailbox {
fn clone(&self) -> Self {
BackendMailbox::clone(self.deref())
}
}
impl Default for Mailbox {
fn default() -> Self {
mailbox_default()
}
}
#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy)]
pub struct MailboxPermissions {
pub create_messages: bool,
pub remove_messages: bool,
pub set_flags: bool,
pub create_child: bool,
pub rename_messages: bool,
pub delete_messages: bool,
pub delete_mailbox: bool,
pub change_permissions: bool,
}
impl Default for MailboxPermissions {
fn default() -> Self {
MailboxPermissions {
create_messages: false,
remove_messages: false,
set_flags: false,
create_child: false,
rename_messages: false,
delete_messages: false,
delete_mailbox: true,
change_permissions: false,
}
}
}
impl std::fmt::Display for MailboxPermissions {
fn fmt(&self, fmt: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(fmt, "{:#?}", self)
}
}