remove hot template reloading

Author: syphar

Cargo.lock

@@ -90,10 +90,6 @@ tempfile = "3.1.0"
 tera = { version = "1.5.0", features = ["builtins"] }
 walkdir = "2"
 
-# Template hot-reloading
-arc-swap = "0.4.6"
-notify = "4.0.15"
-
 # Date and Time utilities
 chrono = { version = "0.4.11", features = ["serde"] }
 time = "0.1" # TODO: Remove once `iron` is removed

Cargo.toml

@@ -75,8 +75,9 @@ cargo run -- build add-essential-files
 # This starts the web server but does not build any crates.
 # It does not automatically run the migrations, so you need to do that manually (see above).
 cargo run -- start-web-server
-# If you want the server to automatically reload templates if they are modified:
-cargo run -- start-web-server --reload-templates
+# If you want the server to automatically restart when code or templates change
+# you can use `cargo-watch`: 
+cargo watch -x "run -- start-web-server"
 ```
 
 If you need to store big files in the repository's directory it's recommended to

README.md

@@ -93,10 +93,6 @@ enum CommandLine {
     StartWebServer {
         #[structopt(name = "SOCKET_ADDR", default_value = "0.0.0.0:3000")]
         socket_addr: String,
-
-        /// Reload templates when they're changed
-        #[structopt(long = "reload-templates")]
-        reload_templates: bool,
     },
 
     /// Starts the daemon
@@ -129,12 +125,9 @@ impl CommandLine {
 
         match self {
             Self::Build(build) => build.handle_args(ctx)?,
-            Self::StartWebServer {
-                socket_addr,
-                reload_templates,
-            } => {
+            Self::StartWebServer { socket_addr } => {
                 // Blocks indefinitely
-                let _ = Server::start(Some(&socket_addr), reload_templates, &ctx)?;
+                let _ = Server::start(Some(&socket_addr), &ctx)?;
             }
             Self::Daemon { registry_watcher } => {
                 docs_rs::utils::start_daemon(&ctx, registry_watcher == Toggle::Enabled)?;

src/bin/cratesfyi.rs

@@ -375,7 +375,7 @@ pub(crate) struct TestFrontend {
 impl TestFrontend {
     fn new(context: &dyn Context) -> Self {
         Self {
-            server: Server::start(Some("127.0.0.1:0"), false, context)
+            server: Server::start(Some("127.0.0.1:0"), context)
                 .expect("failed to start the web server"),
             client: Client::new(),
         }

src/test/mod.rs

@@ -52,7 +52,7 @@ pub fn start_daemon(context: &dyn Context, enable_registry_watcher: bool) -> Res
     // Start the web server before doing anything more expensive
     // Please check with an administrator before changing this (see #1172 for context).
     info!("Starting web server");
-    let server = crate::Server::start(None, false, context)?;
+    let server = crate::Server::start(None, context)?;
     let server_thread = thread::spawn(|| drop(server));
 
     if enable_registry_watcher {

src/utils/daemon.rs

@@ -18,7 +18,7 @@ pub(crate) fn rewrite_lol(
     use lol_html::html_content::{ContentType, Element};
     use lol_html::{HtmlRewriter, MemorySettings, Settings};
 
-    let templates = templates.templates.load();
+    let templates = &templates.templates;
     let tera_head = templates.render("rustdoc/head.html", &ctx).unwrap();
     let tera_vendored_css = templates.render("rustdoc/vendored.html", &ctx).unwrap();
     let tera_body = templates.render("rustdoc/body.html", &ctx).unwrap();

src/utils/html.rs

@@ -415,17 +415,9 @@ pub struct Server {
 }
 
 impl Server {
-    pub fn start(
-        addr: Option<&str>,
-        reload_templates: bool,
-        context: &dyn Context,
-    ) -> Result<Self, Error> {
+    pub fn start(addr: Option<&str>, context: &dyn Context) -> Result<Self, Error> {
         // Initialize templates
         let template_data = Arc::new(TemplateData::new(&mut *context.pool()?.get()?)?);
-        if reload_templates {
-            TemplateData::start_template_reloading(template_data.clone(), context.pool()?);
-        }
-
         let server = Self::start_inner(addr.unwrap_or(DEFAULT_BIND), template_data, context)?;
         info!("Running docs.rs web server on http://{}", server.addr());
         Ok(server)

src/web/mod.rs

@@ -1,19 +1,10 @@
-use crate::{db::Pool, error::Result};
+use crate::error::Result;
 use anyhow::Context;
-use arc_swap::ArcSwap;
 use chrono::{DateTime, Utc};
-use notify::{watcher, RecursiveMode, Watcher};
 use path_slash::PathExt;
 use postgres::Client;
 use serde_json::Value;
-use std::{
-    collections::HashMap,
-    fmt,
-    path::PathBuf,
-    sync::{mpsc::channel, Arc},
-    thread,
-    time::Duration,
-};
+use std::{collections::HashMap, fmt, path::PathBuf};
 use tera::{Result as TeraResult, Tera};
 use walkdir::WalkDir;
 
@@ -22,56 +13,21 @@ const TEMPLATES_DIRECTORY: &str = "templates";
 /// Holds all data relevant to templating
 #[derive(Debug)]
 pub(crate) struct TemplateData {
-    /// The actual templates, stored in an `ArcSwap` so that they're hot-swappable
-    // TODO: Conditional compilation so it's not always wrapped, the `ArcSwap` is unneeded overhead for prod
-    pub templates: ArcSwap<Tera>,
+    pub templates: Tera,
 }
 
 impl TemplateData {
     pub(crate) fn new(conn: &mut Client) -> Result<Self> {
         log::trace!("Loading templates");
 
         let data = Self {
-            templates: ArcSwap::from_pointee(load_templates(conn)?),
+            templates: load_templates(conn)?,
         };
 
         log::trace!("Finished loading templates");
 
         Ok(data)
     }
-
-    pub(crate) fn start_template_reloading(template_data: Arc<TemplateData>, pool: Pool) {
-        let (tx, rx) = channel();
-        // Set a 2 second event debounce for the watcher
-        let mut watcher = watcher(tx, Duration::from_secs(2)).unwrap();
-
-        watcher
-            .watch(TEMPLATES_DIRECTORY, RecursiveMode::Recursive)
-            .unwrap();
-
-        thread::spawn(move || {
-            fn reload(template_data: &TemplateData, pool: &Pool) -> Result<()> {
-                let mut conn = pool.get()?;
-                template_data
-                    .templates
-                    .swap(Arc::new(load_templates(&mut conn)?));
-
-                Ok(())
-            }
-
-            // The watcher needs to be moved into the thread so that it's not dropped (when dropped,
-            // all updates cease)
-            let _watcher = watcher;
-
-            while rx.recv().is_ok() {
-                if let Err(err) = reload(&template_data, &pool) {
-                    log::error!("failed to reload templates: {}", err);
-                } else {
-                    log::info!("reloaded templates");
-                }
-            }
-        });
-    }
 }
 
 fn load_rustc_resource_suffix(conn: &mut Client) -> Result<String> {

src/web/page/templates.rs

@@ -70,7 +70,6 @@ pub trait WebPage: Serialize + Sized {
             .get::<TemplateData>()
             .expect("missing TemplateData from the request extensions")
             .templates
-            .load()
             .render(&self.template(), &ctx);
 
         let rendered = if status.is_server_error() {