pwt.jinja2js is an extension to the Jinja2 template engine that compiles valid Jinja2 templates containing macros to Java Script. The Java Script output can be included via script tags or can be added to the applications Java Script.
It works by mapping each macro in a Jinja2 template to a Java Script function that when called passing in all parameters to the macro as a Java Script object returns a string representing output of the template. For example using the tool we can convert the following template:
{% namespace ns1 %}
{% macro printusers(users) %}
<ul>
{% for user in users %}
<li><a href="{{ user.url }}">{{ user.username }}</a></li>
{% endfor %}
</ul>
{% endmacro %}
to produce the following Java Script to be included in your application:
if (typeof ns1 == 'undefined') { var ns1 = {}; }
ns1.printusers = function(opt_data, opt_sb, opt_caller) {
var output = '';
output += '\n<ul>\n';
var userList = opt_data.users;
var userListLen = userList.length;
for (var userIndex = 0; userIndex < userListLen; userIndex++) {
var userData = userList[userIndex];
output += '\n <li><a href="' + userData.url + '">' + userData.username + '</a></li>\n';
}
output += '\n</ul>\n';
return output;
}
By slipping a switch we can produce Java Script that takes advantage of Closure Library and produces the following:
goog.provide('ns1');
goog.require('soy');
ns1.printusers = function(opt_data, opt_sb) {
var output = opt_sb || new soy.StringBuilder();
output.append('\n<ul>\n');
var userList = opt_data.users;
var userListLen = userList.length;
for (var userIndex = 0; userIndex < userListLen; userIndex++) {
var userData = userList[userIndex];
output.append('\n <li><a href="', userData.url, '">', userData.username, '</a></li>\n');
}
output.append('\n</ul>\n');
if (!opt_sb) return output.toString();
}
Now we can call the macro like so:
document.write(ns1.printusers({users: [
{username: "michael", url: "#user/michael"},
{username: "johndoe", url: "#user/johndoe"}
]})
);
to produce:
<ul>
<li><a href="#user/michael">michael</a></li>
<li><a href="#user/johndoe">johndoe</a></li>
</ul>
Contents: