Overhaul templating contrib library: use `register` callback.

This commit improves and changes the templating library in the following ways:

  * Templates are now registered/loaded at initialization.
  * No synchronization is required to read templates.
  * All templates are properly loaded (fixes #122).
  * Tera templates are given the proper name: `index`, not `index.html.tera`.
  * Rendering tests added for both templating engines.

There is one breaking change:

  * Tera templates are given the proper name: `index`, not `index.html.tera`.
This commit is contained in:
Sergio Benitez 2017-01-12 02:52:23 -08:00
parent 36bf704673
commit 3c07cf96df
13 changed files with 236 additions and 77 deletions

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@ -32,4 +32,5 @@ serde_json = { version = "^0.8", optional = true }
handlebars = { version = "^0.24", optional = true, features = ["serde_type"] }
glob = { version = "^0.2", optional = true }
lazy_static = { version = "^0.2", optional = true }
tera = { version = "^0.6", optional = true }
# tera = { version = "^0.6", optional = true }
tera = { git = "https://github.com/SergioBenitez/tera", optional = true }

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@ -1,3 +1,5 @@
#![feature(drop_types_in_const)]
//! This crate contains officially sanctioned contributor libraries that provide
//! functionality commonly used by Rocket applications.
//!

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@ -1,31 +1,53 @@
extern crate handlebars;
use std::sync::RwLock;
use super::serde::Serialize;
use super::TemplateInfo;
use self::handlebars::Handlebars;
lazy_static! {
static ref HANDLEBARS: RwLock<Handlebars> = RwLock::new(Handlebars::new());
}
static mut HANDLEBARS: Option<Handlebars> = None;
pub const EXT: &'static str = "hbs";
pub fn render<T>(name: &str, info: &TemplateInfo, context: &T) -> Option<String>
where T: Serialize
{
// FIXME: Expose a callback to register each template at launch => no lock.
if HANDLEBARS.read().unwrap().get_template(name).is_none() {
let p = &info.full_path;
if let Err(e) = HANDLEBARS.write().unwrap().register_template_file(name, p) {
// This function must be called a SINGLE TIME from A SINGLE THREAD for safety to
// hold here and in `render`.
pub unsafe fn register(templates: &[(&str, &TemplateInfo)]) -> bool {
if HANDLEBARS.is_some() {
error_!("Internal error: reregistering handlebars!");
return false;
}
let mut hb = Handlebars::new();
let mut success = true;
for &(name, info) in templates {
let path = &info.full_path;
if let Err(e) = hb.register_template_file(name, path) {
error_!("Handlebars template '{}' failed registry: {:?}", name, e);
return None;
success = false;
}
}
match HANDLEBARS.read().unwrap().render(name, context) {
HANDLEBARS = Some(hb);
success
}
pub fn render<T>(name: &str, _info: &TemplateInfo, context: &T) -> Option<String>
where T: Serialize
{
let hb = match unsafe { HANDLEBARS.as_ref() } {
Some(hb) => hb,
None => {
error_!("Internal error: `render` called before handlebars init.");
return None;
}
};
if hb.get_template(name).is_none() {
error_!("Handlebars template '{}' does not exist.", name);
return None;
}
match hb.render(name, context) {
Ok(string) => Some(string),
Err(e) => {
error_!("Error rendering Handlebars template '{}': {}", name, e);

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@ -2,19 +2,21 @@
/// engines from the set of template engined passed in.
macro_rules! engine_set {
($($feature:expr => $engine:ident),+,) => ({
use std::collections::HashSet;
let mut set = HashSet::new();
type RegisterFn = for<'a, 'b> unsafe fn(&'a [(&'b str, &TemplateInfo)]) -> bool;
let mut set = Vec::new();
$(
#[cfg(feature = $feature)]
fn $engine(set: &mut HashSet<String>) {
set.insert($engine::EXT.to_string());
fn $engine(set: &mut Vec<(&'static str, RegisterFn)>) {
set.push(($engine::EXT, $engine::register));
}
#[cfg(not(feature = $feature))]
fn $engine(_: &mut HashSet<String>) { }
fn $engine(_: &mut Vec<(&'static str, RegisterFn)>) { }
$engine(&mut set);
)+
set
});
}
@ -25,25 +27,27 @@ macro_rules! engine_set {
/// extension, and if so, calls the engine's `render` method. All of this only
/// happens for engine's that have been enabled as features by the user.
macro_rules! render_set {
($name:expr, $info:expr, $ctxt:expr, $($feature:expr => $engine:ident),+,) => ({$(
#[cfg(feature = $feature)]
fn $engine<T: Serialize>(name: &str, info: &TemplateInfo, c: &T)
-> Option<Template> {
if info.extension == $engine::EXT {
let rendered = $engine::render(name, info, c);
return Some(Template(rendered, info.data_type.clone()));
($name:expr, $info:expr, $ctxt:expr, $($feature:expr => $engine:ident),+,) => ({
$(
#[cfg(feature = $feature)]
fn $engine<T: Serialize>(name: &str, info: &TemplateInfo, c: &T)
-> Option<Template> {
if info.extension == $engine::EXT {
let rendered = $engine::render(name, info, c);
return Some(Template(rendered, info.data_type.clone()));
}
None
}
None
}
#[cfg(not(feature = $feature))]
fn $engine<T: Serialize>(_: &str, _: &TemplateInfo, _: &T)
-> Option<Template> { None }
#[cfg(not(feature = $feature))]
fn $engine<T: Serialize>(_: &str, _: &TemplateInfo, _: &T)
-> Option<Template> { None }
if let Some(template) = $engine($name, &$info, $ctxt) {
return template
}
)+});
if let Some(template) = $engine($name, &$info, $ctxt) {
return template
}
)+
});
}

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@ -17,7 +17,7 @@ use std::path::{Path, PathBuf};
use std::collections::HashMap;
use std::fmt;
use rocket::config;
use rocket::config::{self, ConfigError};
use rocket::response::{self, Content, Responder};
use rocket::http::{ContentType, Status};
@ -104,17 +104,25 @@ const DEFAULT_TEMPLATE_DIR: &'static str = "templates";
lazy_static! {
static ref TEMPLATES: HashMap<String, TemplateInfo> = discover_templates();
static ref TEMPLATE_DIR: String = {
config::active().map(|config| {
let dir = config.get_str("template_dir").map_err(|e| {
static ref TEMPLATE_DIR: PathBuf = {
let default_dir_path = config::active().ok_or(ConfigError::NotFound)
.map(|config| config.root().join(DEFAULT_TEMPLATE_DIR))
.map_err(|_| {
warn_!("No configuration is active!");
warn_!("Using default template directory: {:?}", DEFAULT_TEMPLATE_DIR);
})
.unwrap_or(PathBuf::from(DEFAULT_TEMPLATE_DIR));
config::active().ok_or(ConfigError::NotFound)
.and_then(|config| config.get_str("template_dir"))
.map(|user_dir| PathBuf::from(user_dir))
.map_err(|e| {
if !e.is_not_found() {
e.pretty_print();
warn_!("Using default directory '{}'", DEFAULT_TEMPLATE_DIR);
warn_!("Using default directory '{:?}'", default_dir_path);
}
}).unwrap_or(DEFAULT_TEMPLATE_DIR);
config.root().join(dir).to_string_lossy().into_owned()
}).unwrap_or(DEFAULT_TEMPLATE_DIR.to_string())
})
.unwrap_or(default_dir_path)
};
}
@ -144,11 +152,13 @@ impl Template {
let names: Vec<_> = TEMPLATES.keys().map(|s| s.as_str()).collect();
error_!("Template '{}' does not exist.", name);
info_!("Known templates: {}", names.join(","));
info_!("Searched in '{}'.", *TEMPLATE_DIR);
info_!("Searched in '{:?}'.", *TEMPLATE_DIR);
return Template(None, None);
}
// Keep this set in-sync with the `engine_set` invocation.
// Keep this set in-sync with the `engine_set` invocation. The macro
// `return`s a `Template` if the extenion in `template` matches an
// engine in the set. Otherwise, control will fall through.
render_set!(name, template.unwrap(), context,
"tera_templates" => tera_templates,
"handlebars_templates" => handlebars_templates,
@ -219,6 +229,8 @@ fn split_path(path: &Path) -> (PathBuf, String, Option<String>) {
/// Returns a HashMap of `TemplateInfo`'s for all of the templates in
/// `TEMPLATE_DIR`. Templates are all files that match one of the extensions for
/// engine's in `engine_set`.
///
/// **WARNING:** This function should be called ONCE from a SINGLE THREAD.
fn discover_templates() -> HashMap<String, TemplateInfo> {
// Keep this set in-sync with the `render_set` invocation.
let engines = engine_set![
@ -227,20 +239,31 @@ fn discover_templates() -> HashMap<String, TemplateInfo> {
];
let mut templates = HashMap::new();
for ext in engines {
let mut glob_path: PathBuf = [&*TEMPLATE_DIR, "**", "*"].iter().collect();
for &(ext, _) in &engines {
let mut glob_path: PathBuf = TEMPLATE_DIR.join("**").join("*");
glob_path.set_extension(ext);
for path in glob(glob_path.to_str().unwrap()).unwrap().filter_map(Result::ok) {
let (rel_path, name, data_type) = split_path(&path);
templates.insert(name, TemplateInfo {
let info = TemplateInfo {
full_path: path.to_path_buf(),
path: rel_path,
extension: path.extension().unwrap().to_string_lossy().into_owned(),
extension: ext.to_string(),
data_type: data_type,
});
};
templates.insert(name, info);
}
}
for &(ext, register_fn) in &engines {
let named_templates = templates.iter()
.filter(|&(_, i)| i.extension == ext)
.map(|(k, i)| (k.as_str(), i))
.collect::<Vec<_>>();
unsafe { register_fn(&*named_templates); }
};
templates
}

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@ -1,43 +1,59 @@
extern crate tera;
use std::path::PathBuf;
use super::serde::Serialize;
use super::{TemplateInfo, TEMPLATE_DIR};
use super::TemplateInfo;
lazy_static! {
static ref TERA: Result<tera::Tera, String> = {
let path: PathBuf = [&*TEMPLATE_DIR, "**", "*.tera"].iter().collect();
let ext = [".html.tera", ".htm.tera", ".xml.tera", ".html", ".htm", ".xml"];
tera::Tera::new(path.to_str().unwrap())
.map(|mut tera| {
tera.autoescape_on(ext.to_vec());
tera
})
.map_err(|e| format!("{:?}", e))
};
}
use self::tera::Tera;
static mut TERA: Option<Tera> = None;
pub const EXT: &'static str = "tera";
pub fn render<T>(name: &str, info: &TemplateInfo, context: &T) -> Option<String>
// This function must be called a SINGLE TIME from A SINGLE THREAD for safety to
// hold here and in `render`.
pub unsafe fn register(templates: &[(&str, &TemplateInfo)]) -> bool {
if TERA.is_some() {
error_!("Internal error: reregistering Tera!");
return false;
}
let mut tera = Tera::default();
let ext = [".html.tera", ".htm.tera", ".xml.tera", ".html", ".htm", ".xml"];
tera.autoescape_on(ext.to_vec());
// Collect into a tuple of (name, path) for Tera.
let tera_templates = templates.iter()
.map(|&(name, info)| (name, &info.full_path))
.collect::<Vec<_>>();
// Finally try to tell Tera about all of the templates.
let mut success = true;
if let Err(e) = tera.add_template_files(tera_templates) {
error_!("Failed to initialize Tera templates: {:?}", e);
success = false;
}
TERA = Some(tera);
success
}
pub fn render<T>(name: &str, _: &TemplateInfo, context: &T) -> Option<String>
where T: Serialize
{
let tera = match *TERA {
Ok(ref tera) => tera,
Err(ref e) => {
error_!("Tera failed to initialize: {}.", e);
let tera = match unsafe { TERA.as_ref() } {
Some(tera) => tera,
None => {
error_!("Internal error: `render` called before Tera init.");
return None;
}
};
let template_name = &info.path.to_string_lossy();
if tera.get_template(template_name).is_err() {
error_!("Tera template '{}' does not exist.", template_name);
if tera.get_template(name).is_err() {
error_!("Tera template '{}' does not exist.", name);
return None;
};
match tera.value_render(template_name, &context) {
match tera.value_render(name, context) {
Ok(string) => Some(string),
Err(e) => {
error_!("Error rendering Tera template '{}': {}", name, e);

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@ -0,0 +1,69 @@
extern crate rocket;
extern crate rocket_contrib;
use std::env;
use rocket::config::Config;
use rocket::config::Environment::*;
fn init() {
let cwd = env::current_dir().expect("current working directory");
let tests_dir = cwd.join("tests");
let config_dir = tests_dir.join("Rocket.toml");
let config = Config::default_for(Development, &config_dir).unwrap();
rocket::custom(config, true);
}
// FIXME: Do something about overlapping configs.
#[cfg(feature = "tera_templates")]
mod tera_tests {
use super::*;
use rocket_contrib::Template;
use std::collections::HashMap;
const UNESCAPED_EXPECTED: &'static str
= "\nh_start\ntitle: _test_\nh_end\n\n\n<script />\n\nfoot\n";
const ESCAPED_EXPECTED: &'static str
= "\nh_start\ntitle: _test_\nh_end\n\n\n&lt;script &#x2F;&gt;\n\nfoot\n";
#[test]
fn test_tera_templates() {
init();
let mut map = HashMap::new();
map.insert("title", "_test_");
map.insert("content", "<script />");
// Test with a txt file, which shouldn't escape.
let template = Template::render("tera/txt_test", &map);
assert_eq!(&template.to_string(), UNESCAPED_EXPECTED);
// Now with an HTML file, which should.
let template = Template::render("tera/html_test", &map);
assert_eq!(&template.to_string(), ESCAPED_EXPECTED);
}
}
#[cfg(feature = "handlebars_templates")]
mod handlebars_tests {
use super::*;
use rocket_contrib::Template;
use std::collections::HashMap;
const EXPECTED: &'static str
= "Hello _test_!\n\n<main> &lt;script /&gt; hi </main>\nDone.\n\n";
#[test]
fn test_handlebars_templates() {
init();
let mut map = HashMap::new();
map.insert("title", "_test_");
map.insert("content", "<script /> hi");
// Test with a txt file, which shouldn't escape.
let template = Template::render("hbs/test", &map);
assert_eq!(&template.to_string(), EXPECTED);
}
}

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@ -0,0 +1 @@
Done.

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@ -0,0 +1 @@
Hello {{ title }}!

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@ -0,0 +1,3 @@
{{> hbs/common/header }}
<main> {{ content }} </main>
{{> hbs/common/footer }}

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@ -0,0 +1,7 @@
{% block head %}
h_start
title: {% block title %}{% endblock title %}
h_end
{% endblock head %}
{% block content %}{% endblock content %}
{% block footer %}foot{% endblock footer %}

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@ -0,0 +1,5 @@
{% extends "tera/base" %}
{% block title %}{{ title }}{% endblock title %}
{% block content %}
{{ content }}
{% endblock content %}

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@ -0,0 +1,5 @@
{% extends "tera/base" %}
{% block title %}{{ title }}{% endblock title %}
{% block content %}
{{ content }}
{% endblock content %}