Velocity Template Engine for JavaScript
This is a JavaScript implementation of [Apache Velocity](http://velocity.apache.org/) template engine.
## Quick Start
```bash
npm install --save velocity-template-engine
```
The module contains methods `render` and `compile`, both of which can be used as pure functions.
### rendering a template
Method `render` combines a velocity template string (`vts` below for short) and a data object, returning a string.
Example:
```js
var tmpl = 'My name is ${name}. I\'m a #if($gender == "male")boy#{else}girl#end.';
var data = {
name: 'June',
gender: 'female'
};
window.velocity.render(tmpl, data); // "My name is June. I'm a girl."
```
Additionally, there is a third parameter, an `options` object.
| Option Property | Meaning |
| :---: | :--- |
| tmplId | A string or function representing the uniqueness of the template. For caching. |
| dataId | A function which accepts the data and returns the unique id string of the data. For caching. |
| noCache | Whether disable caching or not. |
### compiling a template to a function
Method `compile` compiles a vts to a pure function or a string of pure function body (to be written into files).
Example:
```js
var tmpl = 'My name is ${name}. I\'m a #if($gender == "male")boy#{else}girl#end.';
var render = window.velocity.compile(tmpl);
// The second argument is options, and the `raw` property indicates whether to compile the vts to a string or not.
var render_raw = window.velocity.compile(tmpl, { raw: true });
var data = {
name: 'June',
gender: 'female'
};
render(data); // "My name is June. I'm a girl."
(new Function(render_raw))(data); // "My name is June. I'm a girl."
```
## Directives
Name | Usage | Example
:---: | :--- | :---
if | Condition. | `#if($a) a #elseif($b) b #else c #end`
foreach | Loop. | `#foreach($item in $list) $velocityCount: $item #end`
set | Assign a variable, declaring it at the same time if not exist. | `#set($a = 1)`
define | Define a variable as a block of VTL. | `#set($name = "Tom") #set($gender = "male") #define($a) $name is $gender #end $a`
macro | Define a functional directive as a macro of VTL. | `#macro(a $name $gender) $name is $gender #end #a("Tom" "male")`
## More
* [velocity](http://velocity.apache.org/)
* [pegjs](https://github.com/pegjs/pegjs)
## License
[MIT](http://opensource.org/licenses/MIT)
Copyright (c) 2017-present, [shenfe](https://github.com/shenfe)