Add copy-custom-fonts parameter to HtmlConfig to enable custom fonts

Cargo.toml

@@ -18,7 +18,7 @@ description = "Creates a book from markdown files"
 [dependencies]
 anyhow = "1.0.28"
 chrono = "0.4"
-clap = { version = "3.0", features = ["cargo"] }
+clap = { version = "3.1.15", features = ["cargo"] }
 clap_complete = "3.0"
 env_logger = "0.9.0"
 handlebars = "4.0"
@@ -34,6 +34,7 @@ shlex = "1"
 tempfile = "3.0"
 toml = "0.5.1"
 topological-sort = "0.1.0"
+lewp-css = "0.2"
 
 # Watch feature
 notify = { version = "4.0", optional = true }

guide/src/SUMMARY.md

@@ -30,6 +30,7 @@
         - [index.hbs](format/theme/index-hbs.md)
         - [Syntax highlighting](format/theme/syntax-highlighting.md)
         - [Editor](format/theme/editor.md)
+    - [Custom fonts](format/custom-fonts.md)
     - [MathJax Support](format/mathjax.md)
     - [mdBook-specific features](format/mdbook.md)
     - [Markdown](format/markdown.md)

guide/src/format/custom-fonts.md

@@ -0,0 +1,59 @@
+# Custom fonts
+
+It is possible to use custom fonts by using a combination of the parameters
+`copy-fonts` and `copy-custom-fonts`. `copy-fonts` is enabled by default.
+
+The fonts are specified by the `fonts/fonts.css` file, relative to the root directory
+of your book project.
+
+## The copy-fonts option
+
+If `copy-fonts` is enabled, the build in `fonts/fonts.css` file is being copied
+to the output directory. In addition to that, the default fonts are copied to
+the output directory.
+
+## The copy-custom-fonts option
+
+If `copy-custom-fonts` is enabled, the `fonts/fonts.css` file that you have created
+is copied to the output directory. Also, the file gets parsed and searched for
+`@font-face` rules having a `src: url(CUSTOM-FONT)` definition. These `CUSTOM-FONT`
+files are copied to the output directory.
+
+## Enabling both options
+
+It is also possible to use both options in parallel. Then, the build in fonts
+are copied, as well as the custom font files that have been found. The build in
+and the custom definition of `fonts/fonts.css` are combined and copied to the
+output directory as well.
+
+## Example with both options enabled
+
+Create a `fonts/` folder in your book root. Then copy the fonts you want to use
+into this folder (in this example we are assuming `Lato-Regular.ttf`)
+
+Create a custom fonts file `fonts/fonts.css`
+
+```css
+@font-face {
+     font-family: "Lato";
+     font-style: normal;
+     font-weight: normal;
+     src: url('Lato-Regular.ttf');
+}
+```
+
+Setup your `book.toml` that it contains the following parameters:
+
+```toml
+[output.html]
+copy-fonts = true
+copy-custom-fonts = true
+```
+
+Adjust your `theme/css/general.css` file according to your needs, for example:
+
+```css
+html {
+    font-family: "Lato", sans-serif;
+}
+```

src/cmd/build.rs

@@ -1,11 +1,11 @@
 use crate::{get_book_dir, open};
-use clap::{arg, App, Arg, ArgMatches};
+use clap::{arg, Arg, ArgMatches, Command};
 use mdbook::errors::Result;
 use mdbook::MDBook;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("build")
+pub fn make_subcommand<'help>() -> Command<'help> {
+    Command::new("build")
         .about("Builds a book from its markdown files")
         .arg(
             Arg::new("dest-dir")

src/cmd/clean.rs

@@ -1,12 +1,12 @@
 use crate::get_book_dir;
 use anyhow::Context;
-use clap::{arg, App, Arg, ArgMatches};
+use clap::{arg, Arg, ArgMatches, Command};
 use mdbook::MDBook;
 use std::fs;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("clean")
+pub fn make_subcommand<'help>() -> Command<'help> {
+    Command::new("clean")
         .about("Deletes a built book")
         .arg(
             Arg::new("dest-dir")

src/cmd/init.rs

@@ -1,5 +1,5 @@
 use crate::get_book_dir;
-use clap::{arg, App, Arg, ArgMatches};
+use clap::{arg, Arg, ArgMatches, Command as ClapCommand};
 use mdbook::config;
 use mdbook::errors::Result;
 use mdbook::MDBook;
@@ -8,8 +8,8 @@ use std::io::Write;
 use std::process::Command;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("init")
+pub fn make_subcommand<'help>() -> ClapCommand<'help> {
+    ClapCommand::new("init")
         .about("Creates the boilerplate structure and files for a new book")
         // the {n} denotes a newline which will properly aligned in all help messages
         .arg(arg!([dir]

src/cmd/serve.rs

@@ -1,7 +1,7 @@
 #[cfg(feature = "watch")]
 use super::watch;
 use crate::{get_book_dir, open};
-use clap::{arg, App, Arg, ArgMatches};
+use clap::{arg, Arg, ArgMatches, Command};
 use futures_util::sink::SinkExt;
 use futures_util::StreamExt;
 use mdbook::errors::*;
@@ -18,8 +18,8 @@ use warp::Filter;
 const LIVE_RELOAD_ENDPOINT: &str = "__livereload";
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("serve")
+pub fn make_subcommand<'help>() -> Command<'help> {
+    Command::new("serve")
         .about("Serves a book at http://localhost:3000, and rebuilds it on changes")
         .arg(
             Arg::new("dest-dir")

src/cmd/test.rs

@@ -1,11 +1,11 @@
 use crate::get_book_dir;
-use clap::{arg, App, Arg, ArgMatches};
+use clap::{arg, Arg, ArgMatches, Command};
 use mdbook::errors::Result;
 use mdbook::MDBook;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("test")
+pub fn make_subcommand<'help>() -> Command<'help> {
+    Command::new("test")
         .about("Tests that a book's Rust code samples compile")
         .arg(
             Arg::new("dest-dir")
@@ -37,8 +37,8 @@ pub fn make_subcommand<'help>() -> App<'help> {
             .long("library-path")
             .value_name("dir")
             .takes_value(true)
-            .use_delimiter(true)
-            .require_delimiter(true)
+            .use_value_delimiter(true)
+            .require_value_delimiter(true)
             .multiple_values(true)
             .multiple_occurrences(true)
             .forbid_empty_values(true)

src/cmd/watch.rs

@@ -1,5 +1,5 @@
 use crate::{get_book_dir, open};
-use clap::{arg, App, Arg, ArgMatches};
+use clap::{arg, Arg, ArgMatches, Command};
 use mdbook::errors::Result;
 use mdbook::utils;
 use mdbook::MDBook;
@@ -10,8 +10,8 @@ use std::thread::sleep;
 use std::time::Duration;
 
 // Create clap subcommand arguments
-pub fn make_subcommand<'help>() -> App<'help> {
-    App::new("watch")
+pub fn make_subcommand<'help>() -> Command<'help> {
+    Command::new("watch")
         .about("Watches a book's files and rebuilds it on changes")
         .arg(
             Arg::new("dest-dir")

src/config.rs

@@ -489,6 +489,9 @@ pub struct HtmlConfig {
     pub mathjax_support: bool,
     /// Whether to fonts.css and respective font files to the output directory.
     pub copy_fonts: bool,
+    /// If true, find custom font files by parsing the fonts/fonts.css and copy
+    /// them to the output directory.
+    pub copy_custom_fonts: bool,
     /// An optional google analytics code.
     pub google_analytics: Option<String>,
     /// Additional CSS stylesheets to include in the rendered page's `<head>`.
@@ -549,6 +552,7 @@ impl Default for HtmlConfig {
             curly_quotes: false,
             mathjax_support: false,
             copy_fonts: true,
+            copy_custom_fonts: false,
             google_analytics: None,
             additional_css: Vec::new(),
             additional_js: Vec::new(),

src/main.rs

@@ -5,7 +5,7 @@ extern crate log;
 
 use anyhow::anyhow;
 use chrono::Local;
-use clap::{App, AppSettings, Arg, ArgMatches};
+use clap::{Arg, ArgMatches, Command};
 use clap_complete::Shell;
 use env_logger::Builder;
 use log::LevelFilter;
@@ -61,13 +61,13 @@ fn main() {
 }
 
 /// Create a list of valid arguments and sub-commands
-fn create_clap_app() -> App<'static> {
-    let app = App::new(crate_name!())
+fn create_clap_app() -> Command<'static> {
+    let app = Command::new(crate_name!())
         .about(crate_description!())
         .author("Mathieu David <[email protected]>")
         .version(VERSION)
-        .setting(AppSettings::PropagateVersion)
-        .setting(AppSettings::ArgRequiredElseHelp)
+        .propagate_version(true)
+        .arg_required_else_help(true)
         .after_help(
             "For more information about a specific command, try `mdbook <command> --help`\n\
              The source code for mdBook is available at: https://github.com/rust-lang/mdBook",
@@ -77,7 +77,7 @@ fn create_clap_app() -> App<'static> {
         .subcommand(cmd::test::make_subcommand())
         .subcommand(cmd::clean::make_subcommand())
         .subcommand(
-            App::new("completions")
+            Command::new("completions")
                 .about("Generate shell completions for your shell to stdout")
                 .arg(
                     Arg::new("shell")

src/renderer/html_handlebars/hbs_renderer.rs

@@ -289,6 +289,24 @@ impl HtmlHandlebars {
                 theme::fonts::SOURCE_CODE_PRO.1,
             )?;
         }
+        if html_config.copy_custom_fonts {
+            let mut custom_fonts_css = std::fs::read(&Path::new("fonts/fonts.css"))?;
+            if html_config.copy_fonts {
+                // we need to extend the custom fonts file by the build in one
+                // to have the build in ones still available
+                custom_fonts_css.extend(theme::fonts::CSS);
+            }
+            write_file(destination, "fonts/fonts.css", &custom_fonts_css)?;
+            let custom_font_file_names =
+                helpers::custom_fonts::find_custom_font_files(Path::new("fonts/fonts.css"))?;
+            for font_file in custom_font_file_names {
+                write_file(
+                    &Path::new(destination).join("fonts"),
+                    &font_file,
+                    &std::fs::read(&Path::new("fonts").join(&font_file))?,
+                )?;
+            }
+        }
 
         let playground_config = &html_config.playground;
 
@@ -658,6 +676,10 @@ fn make_data(
         data.insert("copy_fonts".to_owned(), json!(true));
     }
 
+    if html_config.copy_custom_fonts {
+        data.insert("copy_custom_fonts".to_owned(), json!(true));
+    }
+
     // Add check to see if there is an additional style
     if !html_config.additional_css.is_empty() {
         let mut css = Vec::new();

src/renderer/html_handlebars/helpers/custom_fonts.rs

@@ -0,0 +1,42 @@
+use crate::errors::Result;
+use lewp_css::{
+    domain::{
+        at_rules::font_face::{FontFaceAtRule, FontUrlSource, Source},
+        CssRule,
+    },
+    Stylesheet,
+};
+use std::path::{Path, PathBuf};
+
+/// Parses the given file_name and extracts the given font file names.
+pub fn find_custom_font_files(css_file_name: &Path) -> Result<Vec<PathBuf>> {
+    let stylesheet = std::fs::read_to_string(css_file_name)?;
+    let stylesheet = Stylesheet::parse(&stylesheet).unwrap_or_else(|_| {
+        panic!(
+            "Stylesheet: \"{}\" could not be parsed!",
+            css_file_name.display()
+        )
+    });
+    let css_rules = stylesheet.rules.0;
+    let mut file_names = vec![];
+    for rule in css_rules {
+        match rule {
+            CssRule::FontFace(font) => {
+                if let Some(f) = extract_font_file_name(font) {
+                    file_names.push(f);
+                }
+            }
+            _ => continue,
+        }
+    }
+    Ok(file_names)
+}
+
+/// Extracts the first file name given in an URL statement from the rule.
+pub fn extract_font_file_name(at_rule: FontFaceAtRule) -> Option<PathBuf> {
+    at_rule.sources.as_ref()?;
+    match at_rule.sources.unwrap().get(0) {
+        Some(Source::Url(FontUrlSource { url, .. })) => Some(PathBuf::from(url.0.clone())),
+        _ => None,
+    }
+}

src/renderer/html_handlebars/helpers/mod.rs

@@ -1,3 +1,4 @@
+pub mod custom_fonts;
 pub mod navigation;
 pub mod theme;
 pub mod toc;

src/theme/index.hbs

@@ -35,7 +35,7 @@
 
         <!-- Fonts -->
         <link rel="stylesheet" href="{{ path_to_root }}FontAwesome/css/font-awesome.css">
-        {{#if copy_fonts}}
+        {{#if (or copy_fonts copy_custom_fonts)}}
         <link rel="stylesheet" href="{{ path_to_root }}fonts/fonts.css">
         {{/if}}