systemd Ready/Stopping notification

CHANGELOG.md

@@ -8,6 +8,10 @@ upgrades, e.g. `v0.6.x` -> `v0.7.x`. The config file format and
 [API](ref/api.md) currently have no stability guarantees, so they may change
 even on minor releases, e.g. `v0.7.5` -> `v0.7.6`.
 
+## unreleased
+
+*  On Linux, notify `systemd` of starting/stopping.
+
 ## v0.7.8 (2023-10-18)
 
 *  release as self-contained Linux binaries (for `x86_64`, `aarch64`, and

guide/install.md

@@ -212,7 +212,8 @@ Environment=TZ=:/etc/localtime
 Environment=MOONFIRE_FORMAT=systemd
 Environment=MOONFIRE_LOG=info
 Environment=RUST_BACKTRACE=1
-Type=simple
+Type=notify
+TimeoutStartSec=300 # large installations take a while to scan the sample file dirs
 User=moonfire-nvr
 Restart=on-failure
 CPUAccounting=true

server/Cargo.lock

@@ -965,6 +965,24 @@ dependencies = [
  "vcpkg",
 ]
 
+[[package]]
+name = "libsystemd"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "88b9597a67aa1c81a6624603e6bd0bcefb9e0f94c9c54970ec53771082104b4e"
+dependencies = [
+ "hmac",
+ "libc",
+ "log",
+ "nix",
+ "nom",
+ "once_cell",
+ "serde",
+ "sha2",
+ "thiserror",
+ "uuid",
+]
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.4.3"
@@ -1125,6 +1143,7 @@ dependencies = [
  "hyper",
  "itertools",
  "libc",
+ "libsystemd",
  "log",
  "memchr",
  "moonfire-base",

server/Cargo.toml

@@ -75,6 +75,9 @@ uuid = { version = "1.1.2", features = ["serde", "std", "v4"] }
 flate2 = "1.0.26"
 git-version = "0.3.5"
 
+[target.'cfg(target_os = "linux")'.dependencies]
+libsystemd = "0.6.0"
+
 [build-dependencies]
 blake3 = "1.0.0"
 fnv = "1.0"

server/src/cmds/run/mod.rs

@@ -22,6 +22,9 @@ use tokio::signal::unix::{signal, SignalKind};
 use tracing::error;
 use tracing::{info, warn};
 
+#[cfg(target_os = "linux")]
+use libsystemd::daemon::{NotifyState, notify};
+
 use self::config::ConfigFile;
 
 pub mod config;
@@ -402,9 +405,23 @@ async fn inner(
         .collect();
     let web_handles = web_handles?;
 
+    #[cfg(target_os = "linux")]
+    {
+        if let Err(err) = notify(false, &[NotifyState::Ready]) {
+            tracing::warn!(%err, "unable to notify systemd on ready");
+        }
+    }
+
     info!("Ready to serve HTTP requests");
     shutdown_rx.as_future().await;
 
+    #[cfg(target_os = "linux")]
+    {
+        if let Err(err) = notify(false, &[NotifyState::Stopping]) {
+            tracing::warn!(%err, "unable to notify systemd on stopping");
+        }
+    }
+
     info!("Shutting down streamers and syncers.");
     tokio::task::spawn_blocking({
         let db = db.clone();