Improved support for systemd autostart.

Cargo.toml

@@ -1,14 +1,13 @@
 [package]
 name = "empress"
-version = "1.0.2"
+version = "1.0.3"
 authors = ["rookie1024 <[email protected]>"]
 edition = "2018"
 description = "A D-Bus MPRIS daemon for controlling media players."
 documentation = "https://docs.rs/empress"
 readme = "README.md"
 repository = "https://github.com/ray-kast/empress"
 license = "AGPL-3.0-or-later"
-license-file = "LICENSE"
 keywords = ["mpris", "music", "play", "pause", "skip"]
 categories = ["command-line-utilities", "multimedia", "os"]
 

README.md

@@ -19,7 +19,7 @@ $ cargo install empress
 ```
 
 Then launch the daemon process in order to use it — you will probably want to
-put this in an rcfile or service definition:
+put this in an rcfile (or see below for setting up a service):
 
 ```sh
 $ empress server
@@ -39,3 +39,32 @@ $ empress play-pause
 The current list of commands includes, `next`, `previous`, `pause`,
 `play-pause`, `stop`, and `play`, which all function as you would expect.  For
 more help you can always run `empress help`.
+
+## Installing `empress` as a Service
+
+`empress` can be installed as a service to allow autostarting and lifecycle
+management using D-Bus and systemd.  To do this, run the following:
+
+```sh
+$ scripts/install-services.sh -l <path to empress binary>
+```
+
+This will install the D-Bus and systemd service files into `~/.local/share`.  If
+you installed `empress` with `cargo install`, the path to the binary will
+probably look something like `/home/<user>/.cargo/bin/empress`.
+
+If you want to make a system-wide installation, simply omit the `-l` flag.  This
+will install the session service files into `/usr` instead (but note that
+`empress` **never** runs as a D-Bus system bus).
+
+### Uninstalling
+
+To remove installed service definitions, simply run:
+
+```sh
+$ scripts/install-services.sh -rl
+```
+
+Like with above, remove the `-l` to uninstall the service files from the system
+folders.
+

etc/empress.service.in

@@ -0,0 +1,13 @@
+# Systemd unit file for empress
+
+[Unit]
+Description=A D-Bus MPRIS daemon for controlling media players.
+Documentation=https://github.com/ray-kast/empress/
+PartOf=graphical-session.target
+
+[Service]
+Type=dbus
+BusName=net.ryan_s.Empress1
+ExecStart=/path/to/empress server
+
+# vim:set ft=systemd:

etc/net.ryan_s.Empress1.service.in

@@ -0,0 +1,8 @@
+# D-Bus service file for empress
+
+[D-BUS Service]
+Name=net.ryan_s.Empress1
+Exec=/path/to/empress server
+SystemdService=empress.service
+
+# vim:set ft=toml:

scripts/install-services.sh

@@ -0,0 +1,95 @@
+#/bin/bash
+
+function usage() {
+  cat <<EOF >&2
+Usage: scripts/install.sh [FLAGS] [PATH]
+
+  Installs (or uninstalls) service files for empress. PATH is an absolute path
+  to the empress binary, and is required if -r is not present.
+
+Flags:
+  -h    Display this message and quit.
+  -l    Install service files to a local directory.
+  -n    Generate service files in target/ but do not install them.
+  -r    Remove already-installed service files.
+EOF
+}
+
+set -e
+
+loc=''
+noop=''
+remove=''
+
+while getopts "hlnr" opt; do
+  case $opt in
+    h)
+      usage
+      exit 0
+      ;;
+    l)
+      loc='1'
+      ;;
+    n)
+      noop='1'
+      ;;
+    r)
+      remove='1'
+      ;;
+    \?)
+      usage
+      exit 1
+      ;;
+  esac
+done
+
+shift $((OPTIND - 1))
+
+if [[ -z "$remove" ]] && (( $# != 1 )); then
+  usage
+  exit 1
+fi
+
+cd "$(dirname "$0")/.."
+
+systemd_file=empress.service
+dbus_file=net.ryan_s.Empress1.service
+
+if [[ -z "$remove" ]]; then
+  sed -e "s:/path/to/empress:$1:" "etc/$systemd_file.in" >"target/$systemd_file"
+  sed -e "s:/path/to/empress:$1:" "etc/$dbus_file.in" >"target/$dbus_file"
+fi
+
+[[ -n "$noop" ]] && exit 0
+
+systemd_dir="/usr/lib/systemd/user/"
+dbus_dir="/usr/share/dbus-1/services/"
+
+if [[ -n "$loc" ]]; then
+  base="$XDG_DATA_HOME"
+
+  [[ -n "$base" ]] || base="$HOME"
+
+  systemd_dir="$base/.local/share/systemd/user"
+  dbus_dir="$base/.local/share/dbus-1/services"
+fi
+
+mkdir -p "$systemd_dir"
+mkdir -p "$dbus_dir"
+
+fail=0
+
+if [[ -z "$remove" ]]; then
+  (
+    install -vDm644 "target/$systemd_file" -t "$systemd_dir" && \
+    install -vDm644 "target/$dbus_file" -t "$dbus_dir"
+  ) || fail=$?
+else
+  mv -v "$systemd_dir/$systemd_file" /tmp || fail=$?
+  mv -v "$dbus_dir/$dbus_file" /tmp || fail=$?
+fi
+
+if [[ -n "$fail" ]]; then
+  echo "ERROR: Installation failed."
+  exit $fail
+fi

scripts/test.sh

@@ -4,8 +4,6 @@ set -e
 
 cd "$(dirname "$0")/.."
 
-ls
-
 cargo build --bin empress
 
 echo $'\x1b[1mStarting server...\x1b[m'

src/client.rs

@@ -1,7 +1,7 @@
-use std::time::Duration;
+use std::{sync::Arc, time::Duration};
 
 use anyhow::{Context, Error};
-use dbus::nonblock::Proxy;
+use dbus::nonblock::{Proxy, SyncConnection};
 use dbus_tokio::connection;
 use tokio::{select, sync::oneshot, task};
 
@@ -20,10 +20,7 @@ pub(super) async fn run(id: MethodId) -> Result {
     let run = async move {
         let proxy = Proxy::new(&*SERVER_NAME, &*SERVER_PATH, Duration::from_secs(2), conn);
 
-        let () = proxy
-            .method_call(&*INTERFACE_NAME, id.to_string(), ())
-            .await
-            .context("failed to contact empress server")?;
+        try_send(&proxy, id).await?;
 
         Ok(())
     };
@@ -35,3 +32,25 @@ pub(super) async fn run(id: MethodId) -> Result {
         ),
     )
 }
+
+async fn try_send(proxy: &Proxy<'_, Arc<SyncConnection>>, id: MethodId) -> Result {
+    const MAX_TRIES: usize = 5;
+
+    let mut i = 0;
+
+    loop {
+        match proxy
+            .method_call(&*INTERFACE_NAME, id.to_string(), ())
+            .await
+            .context("failed to contact empress server")
+        {
+            Err(e) if i < MAX_TRIES => eprintln!("WARNING: {:?}", e),
+            r => break r,
+        }
+
+        i += 1;
+        eprintln!("Retry attempt {:?}", i);
+
+        tokio::time::sleep(Duration::from_millis(20)).await;
+    }
+}

src/main.rs

@@ -1,3 +1,10 @@
+#![warn(missing_docs, clippy::all, clippy::pedantic, clippy::cargo)]
+#![deny(broken_intra_doc_links, missing_debug_implementations)]
+
+//! Binary crate for `empress`.  See [the
+//! README](https://github.com/ray-kast/empress/blob/master/README.md) for more
+//! details.
+
 use anyhow::{Context, Error};
 use lazy_static::lazy_static;
 use structopt::StructOpt;

src/server.rs

@@ -40,7 +40,7 @@ mod mpris {
     }
 
     pub mod player {
-        use super::*;
+        use super::{lazy_static, Interface, Member};
 
         lazy_static! {
             pub static ref INTERFACE: Interface<'static> = "org.mpris.MediaPlayer2.Player".into();
@@ -147,7 +147,7 @@ impl Player {
     }
 
     async fn next(self, conn: &SyncConnection) -> Result<Self> {
-        let () = self.call(&*mpris::player::NEXT, conn).await?;
+        self.call(&*mpris::player::NEXT, conn).await?;
 
         Ok(Self {
             status: self.status,
@@ -157,7 +157,7 @@ impl Player {
     }
 
     async fn previous(self, conn: &SyncConnection) -> Result<Self> {
-        let () = self.call(&*mpris::player::PREVIOUS, conn).await?;
+        self.call(&*mpris::player::PREVIOUS, conn).await?;
 
         Ok(Self {
             status: self.status,
@@ -167,7 +167,7 @@ impl Player {
     }
 
     async fn pause(self, conn: &SyncConnection) -> Result<Self> {
-        let () = self.call(&*mpris::player::PAUSE, conn).await?;
+        self.call(&*mpris::player::PAUSE, conn).await?;
 
         Ok(Self {
             status: PlaybackStatus::Paused,
@@ -177,7 +177,7 @@ impl Player {
     }
 
     async fn stop(self, conn: &SyncConnection) -> Result<Self> {
-        let () = self.call(&*mpris::player::STOP, conn).await?;
+        self.call(&*mpris::player::STOP, conn).await?;
 
         Ok(Self {
             status: PlaybackStatus::Stopped,
@@ -187,7 +187,7 @@ impl Player {
     }
 
     async fn play(self, conn: &SyncConnection) -> Result<Self> {
-        let () = self.call(&*mpris::player::PLAY, conn).await?;
+        self.call(&*mpris::player::PLAY, conn).await?;
 
         Ok(Self {
             status: PlaybackStatus::Playing,
@@ -436,10 +436,19 @@ impl Server {
 
         let self_1 = ret.clone();
         tokio::spawn(async move {
-            while let Some(()) = scan_rx.recv().await {
-                self_1.scan(true).await.unwrap();
+            'main: while let Some(()) = scan_rx.recv().await {
+                loop {
+                    match select!(
+                        opt = scan_rx.recv() => opt.map(|()| false),
+                        () = tokio::time::sleep(Duration::from_millis(200)) => Some(true),
+                    ) {
+                        Some(true) => break,
+                        Some(false) => (),
+                        None => break 'main,
+                    }
+                }
 
-                tokio::time::sleep(Duration::from_millis(200)).await;
+                self_1.scan(true).await.unwrap();
             }
         });