add id mapper to notmuch backend

src/backends/notmuch/notmuch_backend.rs

@@ -3,7 +3,7 @@ use std::{convert::TryInto, fs};
 use anyhow::{anyhow, Context, Result};
 
 use crate::{
-    backends::{Backend, NotmuchEnvelopes, NotmuchMbox, NotmuchMboxes},
+    backends::{Backend, IdMapper, NotmuchEnvelopes, NotmuchMbox, NotmuchMboxes},
     config::{AccountConfig, NotmuchBackendConfig},
     mbox::Mboxes,
     msg::{Envelopes, Msg},
@@ -11,6 +11,7 @@ use crate::{
 
 pub struct NotmuchBackend<'a> {
     account_config: &'a AccountConfig,
+    notmuch_config: &'a NotmuchBackendConfig,
     db: notmuch::Database,
 }
 
@@ -21,6 +22,7 @@ impl<'a> NotmuchBackend<'a> {
     ) -> Result<Self> {
         Ok(Self {
             account_config,
+            notmuch_config,
             db: notmuch::Database::open(
                 notmuch_config.notmuch_database_dir.clone(),
                 notmuch::DatabaseMode::ReadWrite,
@@ -31,6 +33,64 @@ impl<'a> NotmuchBackend<'a> {
             ))?,
         })
     }
+
+    fn _search_envelopes(
+        &mut self,
+        query: &str,
+        virt_mbox: &str,
+        page_size: usize,
+        page: usize,
+    ) -> Result<Box<dyn Envelopes>> {
+        // Gets envelopes matching the given Notmuch query.
+        let query_builder = self
+            .db
+            .create_query(query)
+            .context(format!("cannot create notmuch query from {:?}", query))?;
+        let mut envelopes: NotmuchEnvelopes = query_builder
+            .search_messages()
+            .context(format!(
+                "cannot find notmuch envelopes from query {:?}",
+                query
+            ))?
+            .try_into()
+            .context(format!(
+                "cannot parse notmuch envelopes from query {:?}",
+                query
+            ))?;
+
+        // Calculates pagination boundaries.
+        let page_begin = page * page_size;
+        if page_begin > envelopes.len() {
+            return Err(anyhow!(format!(
+                "cannot find notmuch envelopes at page {:?} (out of bounds)",
+                page_begin + 1,
+            )));
+        }
+        let page_end = envelopes.len().min(page_begin + page_size);
+
+        // Sorts envelopes by most recent date.
+        envelopes.sort_by(|a, b| b.date.partial_cmp(&a.date).unwrap());
+
+        // Applies pagination boundaries.
+        envelopes.0 = envelopes[page_begin..page_end].to_owned();
+
+        // Appends id <=> hash entries to the id mapper cache file.
+        let short_hash_len = {
+            let mut mapper = IdMapper::new(&self.notmuch_config.notmuch_database_dir)?;
+            let entries = envelopes
+                .iter()
+                .map(|env| (env.hash.to_owned(), env.id.to_owned()))
+                .collect();
+            mapper.append(entries)?
+        };
+
+        // Shorten envelopes hash.
+        envelopes
+            .iter_mut()
+            .for_each(|env| env.hash = env.hash[0..short_hash_len].to_owned());
+
+        Ok(Box::new(envelopes))
+    }
 }
 
 impl<'a> Backend<'a> for NotmuchBackend<'a> {
@@ -55,81 +115,44 @@ impl<'a> Backend<'a> for NotmuchBackend<'a> {
 
     fn get_envelopes(
         &mut self,
-        mbox: &str,
+        virt_mbox: &str,
         page_size: usize,
         page: usize,
     ) -> Result<Box<dyn Envelopes>> {
         let query = self
             .account_config
             .mailboxes
-            .get(mbox)
+            .get(virt_mbox)
             .map(|s| s.as_str())
             .unwrap_or("all");
-        let query_builder = self
-            .db
-            .create_query(query)
-            .context("cannot create notmuch query")?;
-        let mut envelopes: NotmuchEnvelopes = query_builder
-            .search_messages()
-            .context(format!(
-                "cannot find notmuch envelopes with query {:?}",
-                query
-            ))?
-            .try_into()?;
-        envelopes.sort_by(|a, b| b.date.partial_cmp(&a.date).unwrap());
-        let page_begin = page * page_size;
-        if page_begin > envelopes.len() {
-            return Err(anyhow!(format!(
-                "cannot find notmuch envelopes at page {:?} (out of bounds)",
-                page_begin + 1,
-            )));
-        }
-        let page_end = envelopes.len().min(page_begin + page_size);
-        envelopes.0 = envelopes[page_begin..page_end].to_owned();
-        Ok(Box::new(envelopes))
+        self._search_envelopes(query, virt_mbox, page_size, page)
     }
 
-    fn find_envelopes(
+    fn search_envelopes(
         &mut self,
-        _mbox: &str,
+        virt_mbox: &str,
         query: &str,
         _sort: &str,
         page_size: usize,
         page: usize,
     ) -> Result<Box<dyn Envelopes>> {
-        let query_builder = self
-            .db
-            .create_query(query)
-            .context("cannot create notmuch query")?;
-        let mut envelopes: NotmuchEnvelopes = query_builder
-            .search_messages()
-            .context(format!(
-                "cannot find notmuch envelopes with query {:?}",
-                query
-            ))?
-            .try_into()?;
-        // TODO: use sort from parameters instead
-        envelopes.sort_by(|a, b| b.date.partial_cmp(&a.date).unwrap());
-        let page_begin = page * page_size;
-        if page_begin > envelopes.len() {
-            return Err(anyhow!(format!(
-                "cannot find notmuch envelopes at page {:?} (out of bounds)",
-                page_begin + 1,
-            )));
-        }
-        let page_end = envelopes.len().min(page_begin + page_size);
-        envelopes.0 = envelopes[page_begin..page_end].to_owned();
-        Ok(Box::new(envelopes))
+        self._search_envelopes(query, virt_mbox, page_size, page)
     }
 
     fn add_msg(&mut self, _mbox: &str, _msg: &[u8], _flags: &str) -> Result<Box<dyn ToString>> {
         unimplemented!();
     }
 
-    fn get_msg(&mut self, _mbox: &str, id: &str) -> Result<Msg> {
+    fn get_msg(&mut self, _mbox: &str, short_hash: &str) -> Result<Msg> {
+        let id = IdMapper::new(&self.notmuch_config.notmuch_database_dir)?
+            .find(short_hash)
+            .context(format!(
+                "cannot get notmuch message from short hash {:?}",
+                short_hash
+            ))?;
         let msg_filepath = self
             .db
-            .find_message(id)
+            .find_message(&id)
             .context(format!("cannot find notmuch message {:?}", id))?
             .ok_or_else(|| anyhow!("cannot find notmuch message {:?}", id))?
             .filename()
@@ -148,10 +171,16 @@ impl<'a> Backend<'a> for NotmuchBackend<'a> {
         unimplemented!();
     }
 
-    fn del_msg(&mut self, _mbox: &str, id: &str) -> Result<()> {
+    fn del_msg(&mut self, _mbox: &str, short_hash: &str) -> Result<()> {
+        let id = IdMapper::new(&self.notmuch_config.notmuch_database_dir)?
+            .find(short_hash)
+            .context(format!(
+                "cannot get notmuch message from short hash {:?}",
+                short_hash
+            ))?;
         let msg_filepath = self
             .db
-            .find_message(id)
+            .find_message(&id)
             .context(format!("cannot find notmuch message {:?}", id))?
             .ok_or_else(|| anyhow!("cannot find notmuch message {:?}", id))?
             .filename()

src/backends/notmuch/notmuch_envelope.rs

@@ -51,6 +51,9 @@ pub struct NotmuchEnvelope {
     /// Represents the id of the message.
     pub id: String,
 
+    /// Represents the MD5 hash of the message id.
+    pub hash: String,
+
     /// Represents the tags of the message.
     pub flags: Vec<String>,
 
@@ -67,7 +70,7 @@ pub struct NotmuchEnvelope {
 impl Table for NotmuchEnvelope {
     fn head() -> Row {
         Row::new()
-            .cell(Cell::new("ID").bold().underline().white())
+            .cell(Cell::new("HASH").bold().underline().white())
             .cell(Cell::new("FLAGS").bold().underline().white())
             .cell(Cell::new("SUBJECT").shrinkable().bold().underline().white())
             .cell(Cell::new("SENDER").bold().underline().white())
@@ -75,14 +78,14 @@ impl Table for NotmuchEnvelope {
     }
 
     fn row(&self) -> Row {
-        let id = self.id.to_string();
+        let hash = self.hash.to_string();
         let unseen = !self.flags.contains(&String::from("unread"));
         let flags = String::new();
         let subject = &self.subject;
         let sender = &self.sender;
         let date = &self.date;
         Row::new()
-            .cell(Cell::new(id).bold_if(unseen).red())
+            .cell(Cell::new(hash).bold_if(unseen).red())
             .cell(Cell::new(flags).bold_if(unseen).white())
             .cell(Cell::new(subject).shrinkable().bold_if(unseen).green())
             .cell(Cell::new(sender).bold_if(unseen).blue())
@@ -117,7 +120,8 @@ impl<'a> TryFrom<RawNotmuchEnvelope> for NotmuchEnvelope {
     fn try_from(raw_envelope: RawNotmuchEnvelope) -> Result<Self, Self::Error> {
         info!("begin: try building envelope from notmuch parsed mail");
 
-        let id = raw_envelope.id().trim().to_string();
+        let id = raw_envelope.id().to_string();
+        let hash = format!("{:x}", md5::compute(&id));
         let subject = raw_envelope
             .header("subject")
             .context("cannot get header \"Subject\" from notmuch message")?
@@ -159,6 +163,7 @@ impl<'a> TryFrom<RawNotmuchEnvelope> for NotmuchEnvelope {
 
         let envelope = Self {
             id,
+            hash,
             flags: raw_envelope.tags().collect(),
             subject,
             sender,