Crate template_fragments

Crate template_fragments 

Source
Expand description

Pre-process Jinja-like templates with fragment tags

template_fragments offers a way to split a template that is annotated with fragment tags ({% fragment NAME %}, {% endfragment %}) into fragments. For example:

<body>
# Header
{% fragment items %}
{% for item in items %}
    {% fragment item %}
        <div>{{ item }}</div>
    {% endfragment %}
{% endfor %}
{% endfragment %}
<body>

This template defines three fragments:

  • "": the whole template without any fragment markers
  • "items": the template looping over all items
  • "item": the innermost div

template_fragments offers two ways to pre-process such a template:

  • filter_template: given a fragment name, only return those parts of the template that belong to the fragment. This function is designed to be used when templates are requested dynamically
  • split_templates: split a template into all its fragments. This function is designed to be used when to extract all templates once at application startup

§Syntax

  • Fragments start with {% fragment NAMES... %} or {% fragment-block NAMES %}
  • {% fragment-block NAME %} and {% endfragment-block %} define fragment blocks: they are rendered as a block, if the fragment is included. This is equivalent to wrapping a block with a fragment of the same name.
  • Fragments end with {% endfragment %} or {% endfragment-block %}
  • Fragments can occur multiple times in the document
  • Multiple fragments can be started in a single tag by using multiple whitespace separated names in the start tag
  • Fragment tags must be contained in a single line and there must not be any other non-whitespace content on the same line
  • Fragment names can contain any alphanumeric character and '-', '_'.

§Example using minijinja

One way to use fragment tags with minijinja is to build a template source with the split templates at application start up like this

use template_fragments::{split_templates, join_path};

let mut source = minijinja::Source::new();

for (path, template) in [("index.html", include_str!("../examples/templates/index.html"))] {
    for (fragment_name, template_fragment) in split_templates(template)? {
        source.add_template(join_path(path, &fragment_name), &template_fragment)?;
    }
}

Note the different fragments can be rendered by requesting the relevant template, e.g., env.get_template("index.html") or env.get_template("index.html#fragment").

Structs§

ErrorWithLine
An error with the line of the template it occurred on

Enums§

Error
Errors that can occurs during processing

Functions§

filter_template
Process the template and return all parts for the given fragment
join_path
Join a path with a fragment (omitting empty fragments)
split_path
Split a template path with optional fragment into the path and fragment
split_templates
Split the template into all fragments available