Module tera 

Text template engine based on Jinja2/Django.

• Crate ::tera.
• docs.rs
• crates.io
• GitHub

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tera is a template engine inspired by Jinja2 and the Django template language. It compiles templates to an internal representation and renders them with a Context holding the variables. Templates support inheritance, includes, for loops, conditionals, filters, and custom functions.

The main entry point is the Tera struct, which loads and caches templates. For one-off rendering without managing a template collection, Tera::one_off renders a template string directly.

Examples

Rendering a template from a string:

use tera::{Tera, Context};

let mut tera = Tera::default();
tera.add_raw_template("greeting", "Hello, {{ name }}!").unwrap();

let mut ctx = Context::new();
ctx.insert("name", "Rust");

let output = tera.render("greeting", &ctx).unwrap();
assert_eq!(output, "Hello, Rust!");

Using loops and conditionals:

use tera::{Tera, Context};

let template = "{% for item in items %}{% if item.active %}{{ item.label }}, {% endif %}{% endfor %}";

let mut tera = Tera::default();
tera.add_raw_template("list", template).unwrap();

let mut ctx = Context::new();
ctx.insert("items", &vec![
    serde_json::json!({"label": "alpha", "active": true}),
    serde_json::json!({"label": "beta", "active": false}),
    serde_json::json!({"label": "gamma", "active": true}),
]);

let output = tera.render("list", &ctx).unwrap();
assert_eq!(output, "alpha, gamma, ");

Quick one-off rendering without creating a Tera instance:

use tera::{Tera, Context};

let mut ctx = Context::new();
ctx.insert("count", &3);

let output = Tera::one_off("There are {{ count }} lights.", &ctx, false).unwrap();
assert_eq!(output, "There are 3 lights.");

Modules

ast

The AST of Tera

helpers

Re-export some helper fns useful to write filters/fns/tests

Macros

try_get_value

Helper macro to get real values out of Value while retaining proper errors in filters

Structs

Context

The struct that holds the context of a template rendering.

Error

The Error type

Map

Represents a JSON key/value type.

Number

Represents a JSON number, whether integer or floating point.

Template

This is the parsed equivalent of a template file. It also does some pre-processing to ensure it does as little as possible at runtime Not meant to be used directly.

Tera

Main point of interaction in this library.

Enums

ErrorKind

The kind of an error (non-exhaustive)

Value

Represents any valid JSON value.

Traits

Filter

The filter function type definition

Function

The global function type definition

Test

The tester function type definition

Functions

dotted_pointer

Lookups a dotted path in a json value contrary to the json slash pointer it’s not allowed to begin with a dot

escape_html

Escape HTML following OWASP

from_value

Interpret a serde_json::Value as an instance of type T.

get_json_pointerDeprecated

Converts a dotted path to a json pointer one

to_value

Convert a T into serde_json::Value which is an enum that can represent any valid JSON data.

Type Aliases

Result

Convenient wrapper around std::Result.