notmuch: auto-locate the notmuch database

1. The notmuch database may not be the same as the maildir.
2. Notmuch has some pretty thorough logic for automatically locating the
database (documented in notmuch(3)).

This change:

1. Renames the `maildir` option to `database` to accurately reflect its
purpose.
2. Makes the `database` option optional.
3. Adds a `profile` option so the user can specify the notmuch profile
they want to use without hard-coding the path to the database.

Author: Stebalien

NEWS.md

@@ -1,8 +1,13 @@
 #  i3status-rust 0.35.0 [unreleased]
 
+### Bug Fixes and Improvements
+
+- The `notmuch` block can now automatically locate the notmuch database (the same way the `notmuch` command does) without being explicitly configured. Furthermore, the block has gained a `profile` option that can be used to specify a notmuch profile other than "default".
+
 ### Breaking Changes
 
 - The `interval` option has been removed from the `notmuch` block in favor of watching the notmuch database for changes.
+- The `maildir` option in the `notmuch` block has been renamed to `database` to better reflect its purpose, and has been made optional.
 
 # i3status-rust 0.34.0
 

src/blocks/notmuch.rs

@@ -43,8 +43,6 @@
 //! # Icons Used
 //! - `mail`
 
-use std::path::Path;
-
 use inotify::{Inotify, WatchMask};
 
 use super::prelude::*;
@@ -53,8 +51,15 @@ use super::prelude::*;
 #[serde(deny_unknown_fields, default)]
 pub struct Config {
     pub format: FormatConfig,
-    #[default("~/.mail".into())]
-    pub maildir: ShellString,
+    /// Path to the notmuch database.
+    ///
+    /// Defaults to the database used by the notmuch CLI tool.
+    pub database: Option<ShellString>,
+    /// Database profile. Cannot be specified at the same time as `database`.
+    ///
+    /// Defaults to the profile used by the notmuch CLI tool.
+    pub profile: Option<String>,
+    /// The notmuch query to count.
     pub query: String,
     #[default(u32::MAX)]
     pub threshold_warning: u32,
@@ -69,17 +74,27 @@ pub struct Config {
 pub async fn run(config: &Config, api: &CommonApi) -> Result<()> {
     let format = config.format.with_default(" $icon $count ")?;
 
-    let db = config.maildir.expand()?;
+    if config.database.is_some() && config.profile.is_some() {
+        return Err(Error::new(
+            "cannot specify both a notmuch database and a notmuch profile",
+        ));
+    }
+
+    let profile = config.profile.as_deref();
+
+    let db_path = config.database.as_ref().map(|p| p.expand()).transpose()?;
+    let db_path: Option<&str> = db_path.as_deref();
     let notify = Inotify::init().error("Failed to start inotify")?;
 
-    for lockpath in ["xapian/flintlock", ".notmuch/xapian/flintlock"] {
-        let fname = Path::new(&*db).join(lockpath);
-        if fname.exists() {
-            notify
-                .watches()
-                .add(fname, WatchMask::CLOSE_WRITE)
-                .error("failed to add inotify watch")?;
-        }
+    {
+        let lock_path = open_database(db_path, profile)
+            .error("failed to open the notmuch database")?
+            .path()
+            .join("xapian/flintlock");
+        notify
+            .watches()
+            .add(lock_path, WatchMask::CLOSE_WRITE)
+            .error("failed to watch the notmuch database lock")?;
     }
 
     let mut updates = notify
@@ -88,7 +103,7 @@ pub async fn run(config: &Config, api: &CommonApi) -> Result<()> {
 
     loop {
         // TODO: spawn_blocking?
-        let count = run_query(&db, &config.query).error("Failed to get count")?;
+        let count = run_query(db_path, profile, &config.query).error("Failed to get count")?;
 
         let mut widget = Widget::new().with_format(format.clone());
 
@@ -118,12 +133,28 @@ pub async fn run(config: &Config, api: &CommonApi) -> Result<()> {
     }
 }
 
-fn run_query(db_path: &str, query_string: &str) -> std::result::Result<u32, notmuch::Error> {
+fn open_database(
+    db_path: Option<&str>,
+    profile: Option<&str>,
+) -> std::result::Result<notmuch::Database, notmuch::Error> {
+    notmuch::Database::open_with_config(
+        db_path,
+        notmuch::DatabaseMode::ReadOnly,
+        None::<&str>,
+        profile,
+    )
+}
+
+fn run_query(
+    db_path: Option<&str>,
+    profile: Option<&str>,
+    query_string: &str,
+) -> std::result::Result<u32, notmuch::Error> {
     let db = notmuch::Database::open_with_config(
-        Some(db_path),
+        db_path,
         notmuch::DatabaseMode::ReadOnly,
         None::<&str>,
-        None,
+        profile,
     )?;
     let query = db.create_query(query_string)?;
     query.count_messages()