jsont 
Simple json template language
Installation
$ component install CamShaft/jsont
Features
- Simple
- Valid JSON
- Extensible
- Auto-parallelization of templated properties
Example
Input:
{
"name": "`user.firstName`",
"birthday": "`user.birthday | date:'MMMM Do'`",
"addresses": "`user.addresses | map | partial:address`"
}
Output:
{
"name": "Cameron",
"birthday": "September 19th",
"addresses": [
{
"street": "123 Fake Street",
"city": "Nowhere",
"country": "USA"
},
{
"street": "Broadway Street",
"city": "NY",
"country": "USA"
}
]
}
Usage
var jsont = require('jsont')();
var template = require('./my-template.json');
var options = {};
jsont.render(template, options, function(err, out) {
console.log(out);
});
Helpers
You can easily extend jsont by calling use:
var jsont = require('jsont')();
jsont.use('reverse', function(input, next) {
next(null, input.split("").reverse().join(""));
});
In your template you can then call the helper by piping data to it:
{
"reversed-name": "'Cameron' | reverse"
}
Out comes:
{
"reversed-name": "noremaC"
}
You can also pass arguments and chain helpers
{
"list": "'1,2,3,4,5' | split:',' | map | to-int"
}
jsont.use('split', function(input, separator, next) {
next(null, input.split(separator));
});
jsont.use('to-int', function(input, next) {
next(null, parseInt(input));
});
And we get:
{
"list": [
1,
2,
3,
4,
5
]
}
Parallelization
Since helpers are all asynchronous behind the scenes we get parallelization in a simple form:
var api = require('./api');
jsont.use('user-likes', function(user, next) {
if (typeof user !== 'object') user = {id: user};
api.likes(user.id, function(err, likes) {
if (err) return next(err);
user.likes = likes;
next(null, user);
});
});
jsont.use('user-followers', function(id, next) {
api.followers(id, next);
});
jsont.use('user', function(id, next) {
api.get(id, function(err, user) {
if (err) return next(err);
user.id = id;
next(null, user);
});
});
jsont.use('length', function(user, property, position, next) {
if (typeof position === 'function') return position(null, user[property].length);
user[position] = user[property].length;
next(null, user);
});
jsont.renderFile('user-profile.json', {id: 0}, function(err, out) {
console.log(out);
});
{
"id": "`id`",
"likes": "`id | user-likes | length:likes`",
"followers": "`id | user-followers | map | user | user-likes | length:likes,likes`"
}
Everything gets put on the event loop and renders as responses come back.
{
"id": "1",
"likes": 4,
"followers": [
{
"id": "2",
"name": "Scott",
"likes": 3
},
{
"id": "3",
"name": "Dave",
"likes": 2
}
]
}
Tests
TODO
-
Create a richer evaluator to do something like:
{
"user": "`{id: id, name: name} | my-helper`"
}
-
Cache compiled templates using the filename option
-
Expose concurrency settings
-
Allow option to configure escape character