Add minification for CSS and JS files

Author: GuillaumeGomez

Cargo.lock

@@ -35,6 +35,7 @@ handlebars = "6.0"
 hex = "0.4.3"
 log = "0.4.17"
 memchr = "2.5.0"
+minifier = "0.3.6"
 opener = "0.8.1"
 pulldown-cmark = { version = "0.10.0", default-features = false, features = ["html"] } # Do not update, part of the public api.
 regex = "1.8.1"

Cargo.toml

@@ -131,18 +131,18 @@ impl BookBuilder {
         }
 
         let mut general_css = File::create(cssdir.join("general.css"))?;
-        general_css.write_all(theme::GENERAL_CSS)?;
+        theme::GENERAL_CSS.write_into(&mut general_css)?;
 
         let mut chrome_css = File::create(cssdir.join("chrome.css"))?;
-        chrome_css.write_all(theme::CHROME_CSS)?;
+        theme::CHROME_CSS.write_into(&mut chrome_css)?;
 
         if html_config.print.enable {
             let mut print_css = File::create(cssdir.join("print.css"))?;
-            print_css.write_all(theme::PRINT_CSS)?;
+            theme::PRINT_CSS.write_into(&mut print_css)?;
         }
 
         let mut variables_css = File::create(cssdir.join("variables.css"))?;
-        variables_css.write_all(theme::VARIABLES_CSS)?;
+        theme::VARIABLES_CSS.write_into(&mut variables_css)?;
 
         let mut favicon = File::create(themedir.join("favicon.png"))?;
         favicon.write_all(theme::FAVICON_PNG)?;
@@ -151,10 +151,10 @@ impl BookBuilder {
         favicon.write_all(theme::FAVICON_SVG)?;
 
         let mut js = File::create(themedir.join("book.js"))?;
-        js.write_all(theme::JS)?;
+        theme::JS.write_into(&mut js)?;
 
         let mut highlight_css = File::create(themedir.join("highlight.css"))?;
-        highlight_css.write_all(theme::HIGHLIGHT_CSS)?;
+        theme::HIGHLIGHT_CSS.write_into(&mut highlight_css)?;
 
         let mut highlight_js = File::create(themedir.join("highlight.js"))?;
         highlight_js.write_all(theme::HIGHLIGHT_JS)?;

src/book/init.rs

@@ -19,17 +19,24 @@ pub static REDIRECT: &[u8] = include_bytes!("templates/redirect.hbs");
 pub static HEADER: &[u8] = include_bytes!("templates/header.hbs");
 pub static TOC_JS: &[u8] = include_bytes!("templates/toc.js.hbs");
 pub static TOC_HTML: &[u8] = include_bytes!("templates/toc.html.hbs");
-pub static CHROME_CSS: &[u8] = include_bytes!("css/chrome.css");
-pub static GENERAL_CSS: &[u8] = include_bytes!("css/general.css");
-pub static PRINT_CSS: &[u8] = include_bytes!("css/print.css");
-pub static VARIABLES_CSS: &[u8] = include_bytes!("css/variables.css");
+pub static CHROME_CSS: ContentToMinify<'static> =
+    ContentToMinify::CSS(include_str!("css/chrome.css"));
+pub static GENERAL_CSS: ContentToMinify<'static> =
+    ContentToMinify::CSS(include_str!("css/general.css"));
+pub static PRINT_CSS: ContentToMinify<'static> =
+    ContentToMinify::CSS(include_str!("css/print.css"));
+pub static VARIABLES_CSS: ContentToMinify<'static> =
+    ContentToMinify::CSS(include_str!("css/variables.css"));
 pub static FAVICON_PNG: &[u8] = include_bytes!("images/favicon.png");
 pub static FAVICON_SVG: &[u8] = include_bytes!("images/favicon.svg");
-pub static JS: &[u8] = include_bytes!("js/book.js");
+pub static JS: ContentToMinify<'static> = ContentToMinify::JS(include_str!("js/book.js"));
 pub static HIGHLIGHT_JS: &[u8] = include_bytes!("js/highlight.js");
-pub static TOMORROW_NIGHT_CSS: &[u8] = include_bytes!("css/tomorrow-night.css");
-pub static HIGHLIGHT_CSS: &[u8] = include_bytes!("css/highlight.css");
-pub static AYU_HIGHLIGHT_CSS: &[u8] = include_bytes!("css/ayu-highlight.css");
+pub static TOMORROW_NIGHT_CSS: ContentToMinify<'static> =
+    ContentToMinify::CSS(include_str!("css/tomorrow-night.css"));
+pub static HIGHLIGHT_CSS: ContentToMinify<'static> =
+    ContentToMinify::CSS(include_str!("css/highlight.css"));
+pub static AYU_HIGHLIGHT_CSS: ContentToMinify<'static> =
+    ContentToMinify::CSS(include_str!("css/ayu-highlight.css"));
 pub static CLIPBOARD_JS: &[u8] = include_bytes!("js/clipboard.min.js");
 pub static FONT_AWESOME: &[u8] = include_bytes!("css/font-awesome.min.css");
 pub static FONT_AWESOME_EOT: &[u8] = include_bytes!("fonts/fontawesome-webfont.eot");
@@ -39,6 +46,31 @@ pub static FONT_AWESOME_WOFF: &[u8] = include_bytes!("fonts/fontawesome-webfont.
 pub static FONT_AWESOME_WOFF2: &[u8] = include_bytes!("fonts/fontawesome-webfont.woff2");
 pub static FONT_AWESOME_OTF: &[u8] = include_bytes!("fonts/FontAwesome.otf");
 
+#[derive(Clone, Copy)]
+pub enum ContentToMinify<'a> {
+    CSS(&'a str),
+    JS(&'a str),
+}
+
+impl<'a> ContentToMinify<'a> {
+    pub fn minified(self) -> Vec<u8> {
+        let mut out = Vec::new();
+        self.write_into(&mut out).unwrap();
+        out
+    }
+
+    pub fn write_into<W: std::io::Write>(self, out: &mut W) -> std::io::Result<()> {
+        match self {
+            Self::CSS(data) => match minifier::css::minify(data) {
+                Ok(data) => return data.write(out),
+                Err(_) => out.write(data.as_bytes())?,
+            },
+            Self::JS(data) => return minifier::js::minify(data).write(out),
+        };
+        Ok(())
+    }
+}
+
 /// The `Theme` struct should be used instead of the static variables because
 /// the `new()` method will look if the user has a theme directory in their
 /// source folder and use the users theme instead of the default.
@@ -181,18 +213,18 @@ impl Default for Theme {
             header: HEADER.to_owned(),
             toc_js: TOC_JS.to_owned(),
             toc_html: TOC_HTML.to_owned(),
-            chrome_css: CHROME_CSS.to_owned(),
-            general_css: GENERAL_CSS.to_owned(),
-            print_css: PRINT_CSS.to_owned(),
-            variables_css: VARIABLES_CSS.to_owned(),
+            chrome_css: CHROME_CSS.minified(),
+            general_css: GENERAL_CSS.minified(),
+            print_css: PRINT_CSS.minified(),
+            variables_css: VARIABLES_CSS.minified(),
             fonts_css: None,
             font_files: Vec::new(),
             favicon_png: Some(FAVICON_PNG.to_owned()),
             favicon_svg: Some(FAVICON_SVG.to_owned()),
-            js: JS.to_owned(),
-            highlight_css: HIGHLIGHT_CSS.to_owned(),
-            tomorrow_night_css: TOMORROW_NIGHT_CSS.to_owned(),
-            ayu_highlight_css: AYU_HIGHLIGHT_CSS.to_owned(),
+            js: JS.minified(),
+            highlight_css: HIGHLIGHT_CSS.minified(),
+            tomorrow_night_css: TOMORROW_NIGHT_CSS.minified(),
+            ayu_highlight_css: AYU_HIGHLIGHT_CSS.minified(),
             highlight_js: HIGHLIGHT_JS.to_owned(),
             clipboard_js: CLIPBOARD_JS.to_owned(),
         }

src/front-end/mod.rs

@@ -1,6 +1,8 @@
 //! Theme dependencies for in-browser search. Not included in mdbook when
 //! the "search" cargo feature is disabled.
 
-pub static JS: &[u8] = include_bytes!("searcher.js");
+use crate::theme::ContentToMinify;
+
+pub static JS: ContentToMinify<'static> = ContentToMinify::JS(include_str!("searcher.js"));
 pub static MARK_JS: &[u8] = include_bytes!("mark.min.js");
 pub static ELASTICLUNR_JS: &[u8] = include_bytes!("elasticlunr.min.js");

src/front-end/searcher/mod.rs

@@ -4,7 +4,7 @@ use crate::errors::*;
 use crate::renderer::html_handlebars::helpers;
 use crate::renderer::html_handlebars::StaticFiles;
 use crate::renderer::{RenderContext, Renderer};
-use crate::theme::{self, Theme};
+use crate::theme::{self, ContentToMinify, Theme};
 use crate::utils;
 
 use std::borrow::Cow;
@@ -396,7 +396,8 @@ impl Renderer for HtmlHandlebars {
         debug!("Render toc js");
         {
             let rendered_toc = handlebars.render("toc_js", &data)?;
-            static_files.add_builtin("toc.js", rendered_toc.as_bytes());
+            let rendered_toc = ContentToMinify::JS(&rendered_toc);
+            static_files.add_owned_builtin("toc.js", rendered_toc.minified());
             debug!("Creating toc.js ✓");
         }
 

src/renderer/html_handlebars/hbs_renderer.rs

@@ -74,7 +74,7 @@ pub fn create_files(
             )
             .as_bytes(),
         );
-        static_files.add_builtin("searcher.js", searcher::JS);
+        static_files.add_owned_builtin("searcher.js", searcher::JS.minified());
         static_files.add_builtin("mark.min.js", searcher::MARK_JS);
         static_files.add_builtin("elasticlunr.min.js", searcher::ELASTICLUNR_JS);
         debug!("Copying search files ✓");

src/renderer/html_handlebars/search.rs

@@ -159,6 +159,10 @@ impl StaticFiles {
     }
 
     pub fn add_builtin(&mut self, filename: &str, data: &[u8]) {
+        self.add_owned_builtin(filename, data.to_owned());
+    }
+
+    pub fn add_owned_builtin(&mut self, filename: &str, data: Vec<u8>) {
         self.static_files.push(StaticFile::Builtin {
             filename: filename.to_owned(),
             data: data.to_owned(),