From b6603468d62207e6ae1c807d4ffe17478ce17766 Mon Sep 17 00:00:00 2001
From: Dylan Owen <dylan.owen@workday.com>
Date: Tue, 12 Nov 2019 18:06:11 -0800
Subject: [PATCH] Stop scrolling on socket reload

---
 src/cmd/serve.rs    | 15 +++++++++++++++
 src/theme/index.hbs |  2 +-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/cmd/serve.rs b/src/cmd/serve.rs
index 3c8c53dc..77843028 100644
--- a/src/cmd/serve.rs
+++ b/src/cmd/serve.rs
@@ -2,6 +2,7 @@
 use super::watch;
 use crate::{get_book_dir, open};
 use clap::{App, Arg, ArgMatches, SubCommand};
+use iron::headers;
 use iron::{status, AfterMiddleware, Chain, Iron, IronError, IronResult, Request, Response, Set};
 use mdbook::errors::*;
 use mdbook::utils;
@@ -9,6 +10,8 @@ use mdbook::MDBook;
 
 struct ErrorRecover;
 
+struct NoCache;
+
 // Create clap subcommand arguments
 pub fn make_subcommand<'a, 'b>() -> App<'a, 'b> {
     SubCommand::with_name("serve")
@@ -86,6 +89,7 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     book.build()?;
 
     let mut chain = Chain::new(staticfile::Static::new(book.build_dir_for("html")));
+    chain.link_after(NoCache);
     chain.link_after(ErrorRecover);
     let _iron = Iron::new(chain)
         .http(&*address)
@@ -133,6 +137,17 @@ pub fn execute(args: &ArgMatches) -> Result<()> {
     Ok(())
 }
 
+impl AfterMiddleware for NoCache {
+    fn after(&self, _: &mut Request, mut res: Response) -> IronResult<Response> {
+        res.headers.set(headers::CacheControl(vec![
+            headers::CacheDirective::NoStore,
+            headers::CacheDirective::MaxAge(0u32),
+        ]));
+
+        Ok(res)
+    }
+}
+
 impl AfterMiddleware for ErrorRecover {
     fn catch(&self, _: &mut Request, err: IronError) -> IronResult<Response> {
         match err.response.status {
diff --git a/src/theme/index.hbs b/src/theme/index.hbs
index 3a0cb4a8..b205670f 100644
--- a/src/theme/index.hbs
+++ b/src/theme/index.hbs
@@ -204,7 +204,7 @@
             socket.onmessage = function (event) {
                 if (event.data === "reload") {
                     socket.close();
-                    location.reload(true); // force reload from server (not from cache)
+                    location.reload();
                 }
             };