Replace tera filters with macros

src/blogs.rs

@@ -37,12 +37,12 @@ pub struct Blog {
     maintained_by: String,
     index_html: String,
     #[serde(serialize_with = "add_postfix_slash")]
-    prefix: PathBuf,
-    posts: Vec<Post>,
+    path: PathBuf,
+    pages: Vec<Post>,
 }
 
 impl Blog {
-    fn load(prefix: PathBuf, dir: &Path) -> eyre::Result<Self> {
+    fn load(path: PathBuf, dir: &Path) -> eyre::Result<Self> {
         let manifest_content = std::fs::read_to_string(dir.join(MANIFEST_FILE))?
             .strip_prefix("+++\n")
             .unwrap()
@@ -94,8 +94,8 @@ impl Blog {
             maintained_by: manifest.maintained_by,
             index_html: manifest.index_html,
             link_text: manifest.link_text,
-            prefix,
-            posts,
+            path,
+            pages: posts,
         })
     }
 
@@ -111,12 +111,12 @@ impl Blog {
         &self.index_title
     }
 
-    pub(crate) fn prefix(&self) -> &Path {
-        &self.prefix
+    pub(crate) fn path(&self) -> &Path {
+        &self.path
     }
 
     pub(crate) fn posts(&self) -> &[Post] {
-        &self.posts
+        &self.pages
     }
 }
 
@@ -139,10 +139,10 @@ fn load_recursive(base: &Path, current: &Path, blogs: &mut Vec<Blog>) -> eyre::R
             let file_name = path.file_name().and_then(|n| n.to_str());
             if let (Some(file_name), Some(parent)) = (file_name, path.parent()) {
                 if file_name == MANIFEST_FILE {
-                    let prefix = parent
+                    let path = parent
                         .strip_prefix(base)
                         .map_or_else(|_| PathBuf::new(), Path::to_path_buf);
-                    blogs.push(Blog::load(prefix, parent)?);
+                    blogs.push(Blog::load(path, parent)?);
                 }
             }
         }

src/lib.rs

@@ -9,7 +9,6 @@ use rayon::prelude::*;
 use sass_rs::{Options, compile_file};
 use serde::Serialize;
 use serde_json::{Value, json};
-use std::collections::HashMap;
 use std::fs::{self, File};
 use std::io::{self, Write};
 use std::path::{Path, PathBuf};
@@ -33,53 +32,12 @@ struct ReleasePost {
     url: String,
 }
 
-fn month_name(month_num: &Value, _args: &HashMap<String, Value>) -> tera::Result<Value> {
-    let month_num = month_num
-        .as_u64()
-        .expect("month_num should be an unsigned integer");
-    let name = match month_num {
-        1 => "Jan.",
-        2 => "Feb.",
-        3 => "Mar.",
-        4 => "Apr.",
-        5 => "May",
-        6 => "June",
-        7 => "July",
-        8 => "Aug.",
-        9 => "Sept.",
-        10 => "Oct.",
-        11 => "Nov.",
-        12 => "Dec.",
-        _ => panic!("invalid month! ({month_num})"),
-    };
-    Ok(name.into())
-}
-
-// Tera and Handlebars escape HTML differently by default.
-// Tera:       &<>"'/
-// Handlebars: &<>"'`=
-// To make the transition testable, this function escapes just like Handlebars.
-fn escape_hbs(input: &Value, _args: &HashMap<String, Value>) -> tera::Result<Value> {
-    let input = input.as_str().expect("input should be a string");
-    Ok(input
-        .replace("&", "&amp;")
-        .replace("<", "&lt;")
-        .replace(">", "&gt;")
-        .replace("\"", "&quot;")
-        .replace("'", "&#x27;")
-        .replace("`", "&#x60;")
-        .replace("=", "&#x3D;")
-        .into())
-}
-
 impl Generator {
     fn new(
         out_directory: impl AsRef<Path>,
         posts_directory: impl AsRef<Path>,
     ) -> eyre::Result<Self> {
         let mut tera = Tera::new("templates/*")?;
-        tera.register_filter("month_name", month_name);
-        tera.register_filter("escape_hbs", escape_hbs);
         tera.autoescape_on(vec![]); // disable auto-escape for .html templates
         Ok(Generator {
             tera,
@@ -148,7 +106,7 @@ impl Generator {
     }
 
     fn render_blog(&self, blog: &Blog) -> eyre::Result<()> {
-        std::fs::create_dir_all(self.out_directory.join(blog.prefix()))?;
+        std::fs::create_dir_all(self.out_directory.join(blog.path()))?;
 
         let path = self.render_index(blog)?;
 
@@ -177,24 +135,24 @@ impl Generator {
             .map(|other_blog| {
                 json!({
                     "link_text": other_blog.link_text(),
-                    "url": other_blog.prefix().join("index.html"),
+                    "url": other_blog.path().join("index.html"),
                 })
             })
             .collect();
 
         let data = json!({
             "title": blog.index_title(),
-            "blog": blog,
+            "section": blog,
             "other_blogs": other_blogs,
         });
-        let path = blog.prefix().join("index.html");
+        let path = blog.path().join("index.html");
         self.render_template(&path, "index.html", data)?;
         Ok(path)
     }
 
     fn render_post(&self, blog: &Blog, post: &Post) -> eyre::Result<PathBuf> {
         let path = blog
-            .prefix()
+            .path()
             .join(format!("{:04}", &post.year))
             .join(format!("{:02}", &post.month))
             .join(format!("{:02}", &post.day));
@@ -206,8 +164,8 @@ impl Generator {
 
         let data = json!({
             "title": format!("{} | {}", post.title, blog.title()),
-            "blog": blog,
-            "post": post,
+            "section": blog,
+            "page": post,
         });
 
         let path = path.join(filename);
@@ -218,12 +176,12 @@ impl Generator {
     fn render_feed(&self, blog: &Blog) -> eyre::Result<()> {
         let posts: Vec<_> = blog.posts().iter().take(10).collect();
         let data = json!({
-            "blog": blog,
-            "posts": posts,
+            "section": blog,
+            "pages": posts,
             "feed_updated": chrono::Utc::now().with_nanosecond(0).unwrap().to_rfc3339(),
         });
 
-        self.render_template(blog.prefix().join("feed.xml"), "feed.xml", data)?;
+        self.render_template(blog.path().join("feed.xml"), "feed.xml", data)?;
         Ok(())
     }
 
@@ -235,8 +193,8 @@ impl Generator {
             .map(|post| ReleasePost {
                 title: post.title.clone(),
                 url: blog
-                    .prefix()
-                    .join(post.url.clone())
+                    .path()
+                    .join(post.path.clone())
                     .to_string_lossy()
                     .to_string(),
             })
@@ -246,7 +204,7 @@ impl Generator {
             feed_updated: chrono::Utc::now().with_nanosecond(0).unwrap().to_rfc3339(),
         };
         fs::write(
-            self.out_directory.join(blog.prefix()).join("releases.json"),
+            self.out_directory.join(blog.path()).join("releases.json"),
             serde_json::to_string(&data)?,
         )?;
         Ok(())

src/posts.rs

@@ -19,7 +19,7 @@ pub struct Post {
     pub(crate) month: u8,
     pub(crate) day: u8,
     pub(crate) contents: String,
-    pub(crate) url: String,
+    pub(crate) path: String,
     pub(crate) published: String,
     pub(crate) updated: String,
     pub(crate) release: bool,
@@ -122,7 +122,7 @@ impl Post {
             month,
             day,
             contents,
-            url,
+            path: url,
             published,
             updated,
             release,

templates/feed.xml

@@ -1,28 +1,29 @@
+{% import "macros.html" as macros %}
 <?xml version="1.0" encoding="utf-8"?>
 <feed xmlns="http://www.w3.org/2005/Atom" xml:lang="en">
-    <generator uri="https://blog.rust-lang.org/{{blog.prefix}}" version="0.1.0">{{blog.title}}</generator>
-    <link href="https://blog.rust-lang.org/{{blog.prefix}}feed.xml" rel="self" type="application/atom+xml" />
-    <link href="https://blog.rust-lang.org/{{blog.prefix}}" rel="alternate" type="text/html" />
-    <id>https://blog.rust-lang.org/{{blog.prefix}}</id>
-    <title>{{blog.title}}</title>
-    <subtitle>{{blog.description}}</subtitle>
+    <generator uri="https://blog.rust-lang.org/{{ section.path }}" version="0.1.0">{{ section.title }}</generator>
+    <link href="https://blog.rust-lang.org/{{ section.path }}feed.xml" rel="self" type="application/atom+xml" />
+    <link href="https://blog.rust-lang.org/{{ section.path }}" rel="alternate" type="text/html" />
+    <id>https://blog.rust-lang.org/{{ section.path }}</id>
+    <title>{{ section.title }}</title>
+    <subtitle>{{ section.description }}</subtitle>
     <author>
-        <name>Maintained by {{blog.maintained_by}}.</name>
+        <name>Maintained by {{ section.maintained_by }}.</name>
         <uri>https://github.com/rust-lang/blog.rust-lang.org/</uri>
     </author>
     <updated>{{feed_updated}}</updated>
 
-    {% for post in posts %}
+    {% for page in pages %}
     <entry>
-        <title>{{post.title | escape_hbs}}</title>
-        <link rel="alternate" href="https://blog.rust-lang.org/{{blog.prefix}}{{post.url | escape_hbs}}" type="text/html" title="{{post.title | escape_hbs}}" />
-        <published>{{post.published | escape_hbs}}</published>
-        <updated>{{post.updated | escape_hbs}}</updated>
-        <id>https://blog.rust-lang.org/{{blog.prefix}}{{post.url | escape_hbs}}</id>
-        <content type="html" xml:base="https://blog.rust-lang.org/{{blog.prefix}}{{post.url | escape_hbs}}">{{post.contents | escape_hbs}}</content>
+        <title>{{ macros::escape_hbs(input=page.title) }}</title>
+        <link rel="alternate" href="https://blog.rust-lang.org/{{ section.path }}{{ macros::escape_hbs(input=page.path) }}" type="text/html" title="{{ macros::escape_hbs(input=page.title) }}" />
+        <published>{{ macros::escape_hbs(input=page.published) }}</published>
+        <updated>{{ macros::escape_hbs(input=page.updated) }}</updated>
+        <id>https://blog.rust-lang.org/{{ section.path }}{{ macros::escape_hbs(input=page.path) }}</id>
+        <content type="html" xml:base="https://blog.rust-lang.org/{{ section.path }}{{ macros::escape_hbs(input=page.path) }}">{{ macros::escape_hbs(input=page.contents) }}</content>
 
         <author>
-            <name>{{post.author | escape_hbs}}</name>
+            <name>{{ macros::escape_hbs(input=page.author) }}</name>
         </author>
     </entry>
     {%- endfor %}

templates/headers.html

@@ -1,15 +1,15 @@
-{% macro headers(title, blog) -%}
+{% macro headers(title, section) -%}
  <!-- Twitter card -->
  <meta name="twitter:card" content="summary">
  <meta name="twitter:site" content="@rustlang">
  <meta name="twitter:creator" content="@rustlang">
- <meta name="twitter:title" content="{{title | escape_hbs}}">
- <meta name="twitter:description" content="{{blog.description}}">
+ <meta name="twitter:title" content="{{ macros::escape_hbs(input=title) }}">
+ <meta name="twitter:description" content="{{ section.description }}">
 <meta name="twitter:image" content="https://www.rust-lang.org/static/images/rust-social.jpg">
 
 <!-- Facebook OpenGraph -->
-<meta property="og:title" content="{{title | escape_hbs}}" />
-<meta property="og:description" content="{{blog.description}}">
+<meta property="og:title" content="{{ macros::escape_hbs(input=title) }}" />
+<meta property="og:description" content="{{ section.description }}">
 <meta property="og:image" content="https://www.rust-lang.org/static/images/rust-social-wide.jpg" />
 <meta property="og:type" content="website" />
 <meta property="og:locale" content="en_US" />
@@ -36,7 +36,7 @@
 <meta name="theme-color" content="#ffffff">
 
  <!-- atom -->
- <link type="application/atom+xml" rel="alternate" href="https://blog.rust-lang.org/{{blog.prefix}}feed.xml" title="{{blog.title}}" />
+ <link type="application/atom+xml" rel="alternate" href="https://blog.rust-lang.org/{{ section.path }}feed.xml" title="{{ section.title }}" />
 
 <!-- theme switcher -->
 <script src="/scripts/theme-switch.js"></script>

templates/index.html

@@ -1,17 +1,18 @@
+{% import "macros.html" as macros %}
 {% extends "layout.html" %}
 {% block page %}
 <header class="mt3 mt0-ns mb4-ns">
   <div class="container flex flex-column flex-row-l justify-between-l">
     <div class="mw6-l">
-      <p>{{blog.index_html}}</p>
+      <p>{{ section.index_html }}</p>
     </div>
   </div>    
   <div class="container flex flex-column flex-row-l justify-between-l">
     <div class="mw8-l">
       <p>
       <b>See also:</b>
       {%- for other in other_blogs %}
-              <a href="/{{other.url}}">{{other.link_text | escape_hbs}}</a>
+              <a href="/{{other.url}}">{{ macros::escape_hbs(input=other.link_text) }}</a>
       {%- endfor %}
       </p>
     </div>
@@ -22,14 +23,14 @@
    <div class="w-100 mw-none ph3 mw8-m mw9-l center f3">
 
     <table class="post-list collapse w-100 f2-l f2-m f3-s">
-    {%- for post in blog.posts %}
-      {% if post.show_year %}<tr>
+    {%- for page in section.pages %}
+      {% if page.show_year %}<tr>
         <td class="bn"></td>
-        <td class="bn"><h3 class="f0-l f1-m f2-s mt4 mb0">Posts in {{post.year}}</h3></td>
+        <td class="bn"><h3 class="f0-l f1-m f2-s mt4 mb0">Posts in {{ page.year }}</h3></td>
       </tr>{% endif %}
       <tr>
-        <td class="tr o-60 pr4 pr5-l bn">{{post.month | month_name}}&nbsp;{{post.day}}</td>
-        <td class="bn"><a href="{{post.url}}">{{post.title | escape_hbs}}</a></td>
+        <td class="tr o-60 pr4 pr5-l bn">{{ macros::month_name(num=page.month) }}&nbsp;{{ page.day }}</td>
+        <td class="bn"><a href="{{ page.path }}">{{ macros::escape_hbs(input=page.title) }}</a></td>
       </tr>
     {%- endfor %}
     </table>

templates/layout.html

@@ -1,17 +1,18 @@
+{% import "macros.html" as macros %}
 {% import "headers.html" as headers %}
 {% import "nav.html" as nav %}
 {% import "footer.html" as footer %}
 <!DOCTYPE html>
 <html lang="en">
   <head>
     <meta charset="utf-8">
-    <title>{{ title | escape_hbs }}</title>
+    <title>{{ macros::escape_hbs(input=title) }}</title>
     <meta name="viewport" content="width=device-width,initial-scale=1.0">
 <meta name="description" content="Empowering everyone to build reliable and efficient software.">
-     {{ headers::headers(title=title, blog=blog) | indent(prefix="    ", blank=true) }}
+     {{ headers::headers(title=title, section=section) | indent(prefix="    ", blank=true) }}
   </head>
   <body>
-    {{ nav::nav(blog=blog) | indent(prefix="    ", blank=true) }}
+    {{ nav::nav(section=section) | indent(prefix="    ", blank=true) }}
     {%- block page %}{% endblock page %}
     {{ footer::footer() | indent(prefix="    ", blank=true) }}
   </body>

templates/macros.html

@@ -0,0 +1,35 @@
+{% macro month_name(num) %}
+    {%- if     num == 1 %}Jan.
+    {%- elif num == 2 %}Feb.
+    {%- elif num == 3 %}Mar.
+    {%- elif num == 4 %}Apr.
+    {%- elif num == 5 %}May
+    {%- elif num == 6 %}June
+    {%- elif num == 7 %}July
+    {%- elif num == 8 %}Aug.
+    {%- elif num == 9 %}Sept.
+    {%- elif num == 10 %}Oct.
+    {%- elif num == 11 %}Nov.
+    {%- elif num == 12 %}Dec.
+    {%- else %}{{ throw(message="invalid month! " ~ num) }}
+    {%- endif %}
+{%- endmacro month_name %}
+
+{#
+    The blog templates used to be written in Handlebars, but Tera and Handlebars
+    escape HTML differently by default:
+    Tera:       &<>"'/
+    Handlebars: &<>"'`=
+    To keep the output identical, this macro matches the behavior of Handlebars.
+#}
+{% macro escape_hbs(input) -%}
+    {{ input
+        | replace(from="&", to="&amp;")
+        | replace(from="<", to="&lt;")
+        | replace(from=">", to="&gt;")
+        | replace(from='"', to="&quot;")
+        | replace(from="'", to="&#x27;")
+        | replace(from="`", to="&#x60;")
+        | replace(from="=", to="&#x3D;")
+    }}
+{%- endmacro escape_hbs %}