From 3c01a822fde54e38da19a94c49e1ef17075b263f Mon Sep 17 00:00:00 2001
From: Paul Campbell <pcampbell@kemitix.net>
Date: Sun, 1 Sep 2024 13:10:14 +0100
Subject: [PATCH] feat: improved error display when startup fails

---
 crates/cli/src/file_watcher.rs | 24 ++++++++++-----------
 crates/cli/src/main.rs         | 31 +++++++++++++--------------
 crates/cli/src/server/mod.rs   | 38 +++++++++++++++++++++++++++++-----
 3 files changed, 61 insertions(+), 32 deletions(-)

diff --git a/crates/cli/src/file_watcher.rs b/crates/cli/src/file_watcher.rs
index eac23b7..a85d70a 100644
--- a/crates/cli/src/file_watcher.rs
+++ b/crates/cli/src/file_watcher.rs
@@ -3,16 +3,17 @@ use actix::prelude::*;
 
 use actix::Recipient;
 use anyhow::{Context, Result};
-use notify::event::ModifyKind;
-use notify::Watcher;
-use tracing::error;
-use tracing::info;
+use notify::{event::ModifyKind, Watcher};
+use tracing::{error, info};
 
-use std::path::PathBuf;
-use std::sync::atomic::AtomicBool;
-use std::sync::atomic::Ordering;
-use std::sync::Arc;
-use std::time::Duration;
+use std::{
+    path::PathBuf,
+    sync::{
+        atomic::{AtomicBool, Ordering},
+        Arc,
+    },
+    time::Duration,
+};
 
 #[derive(Debug, Message)]
 #[rtype(result = "()")]
@@ -30,8 +31,7 @@ pub fn watch_file(path: PathBuf, recipient: Recipient<FileUpdated>) -> Result<Ar
     let mut handler = notify::recommended_watcher(tx).context("file watcher")?;
     handler
         .watch(&path, notify::RecursiveMode::NonRecursive)
-        .with_context(|| format!("Watch file: {path:?}"))?;
-    info!("Watching: {:?}", path);
+        .with_context(|| format!("Watching: {path:?}"))?;
     let thread_shutdown = shutdown.clone();
     actix_rt::task::spawn_blocking(move || {
         loop {
@@ -43,7 +43,7 @@ pub fn watch_file(path: PathBuf, recipient: Recipient<FileUpdated>) -> Result<Ar
                 match result {
                     Ok(event) => match event.kind {
                         notify::EventKind::Modify(ModifyKind::Data(_)) => {
-                            tracing::info!("File modified");
+                            info!("File modified");
                             recipient.do_send(FileUpdated);
                             break;
                         }
diff --git a/crates/cli/src/main.rs b/crates/cli/src/main.rs
index b93a3df..21a9b41 100644
--- a/crates/cli/src/main.rs
+++ b/crates/cli/src/main.rs
@@ -53,24 +53,25 @@ fn main() -> Result<()> {
     let commands = Commands::parse();
 
     match commands.command {
-        Command::Init => {
-            init::run(&fs)?;
-        }
+        Command::Init => init::run(&fs),
         Command::Server(server) => match server {
-            Server::Init => {
-                server::init(&fs)?;
-            }
+            Server::Init => server::init(&fs),
             #[cfg(not(feature = "tui"))]
-            Server::Start {} => {
-                let sleep_duration = std::time::Duration::from_secs(10);
-                server::start(false, fs, net, repository_factory, sleep_duration)?;
-            }
+            Server::Start {} => server::start(
+                false,
+                fs,
+                net,
+                repository_factory,
+                std::time::Duration::from_secs(10),
+            ),
             #[cfg(feature = "tui")]
-            Server::Start { ui } => {
-                let sleep_duration = std::time::Duration::from_secs(10);
-                server::start(ui, fs, net, repository_factory, sleep_duration)?;
-            }
+            Server::Start { ui } => server::start(
+                ui,
+                fs,
+                net,
+                repository_factory,
+                std::time::Duration::from_secs(10),
+            ),
         },
     }
-    Ok(())
 }
diff --git a/crates/cli/src/server/mod.rs b/crates/cli/src/server/mod.rs
index 31ff89c..c63a781 100644
--- a/crates/cli/src/server/mod.rs
+++ b/crates/cli/src/server/mod.rs
@@ -19,9 +19,13 @@ use git_next_core::git::RepositoryFactory;
 
 use color_eyre::{eyre::Context, Result};
 use kxio::{fs::FileSystem, network::Network};
-use tracing::info;
+use tracing::{error, info};
 
-use std::{path::PathBuf, sync::atomic::Ordering, time::Duration};
+use std::{
+    path::PathBuf,
+    sync::{atomic::Ordering, Arc, RwLock},
+    time::Duration,
+};
 
 const A_DAY: Duration = Duration::from_secs(24 * 60 * 60);
 
@@ -57,6 +61,8 @@ pub fn start(
         init_logging();
     }
 
+    let file_watcher_err_channel: Arc<RwLock<Option<anyhow::Error>>> = Arc::new(RwLock::new(None));
+    let file_watcher_err_channel_exec = file_watcher_err_channel.clone();
     let execution = async move {
         info!("Starting Alert Dispatcher...");
         let alerts_addr = AlertsActor::new(None, History::new(A_DAY), net.clone()).start();
@@ -66,9 +72,20 @@ pub fn start(
             ServerActor::new(fs.clone(), net.clone(), alerts_addr, repo, sleep_duration).start();
 
         info!("Starting File Watcher...");
-        #[allow(clippy::expect_used)]
-        let fw_shutdown = watch_file("git-next-server.toml".into(), server.clone().recipient())
-            .expect("file watcher");
+        let watch_file = watch_file("git-next-server.toml".into(), server.clone().recipient());
+        let fw_shutdown = match watch_file {
+            Ok(fw_shutdown) => fw_shutdown,
+            Err(err) => {
+                // shutdown now
+                server.do_send(crate::server::actor::messages::Shutdown);
+                actix_rt::time::sleep(std::time::Duration::from_millis(10)).await;
+                System::current().stop();
+                let _ = file_watcher_err_channel_exec
+                    .write()
+                    .map(|mut o| o.replace(err));
+                return;
+            }
+        };
 
         if ui {
             #[cfg(feature = "tui")]
@@ -106,6 +123,17 @@ pub fn start(
     let system = System::new();
     Arbiter::current().spawn(execution);
     system.run()?;
+
+    // check for error from file watcher thread
+    #[allow(clippy::unwrap_used)]
+    if let Some(err) = &*file_watcher_err_channel.read().unwrap() {
+        if ui {
+            eprintln!("File Watcher: {err:?}");
+        }
+        error!(?err, "file watcher");
+        return Err(color_eyre::eyre::eyre!(format!("{err}")));
+    }
+
     Ok(())
 }