Hanjst

Hanjst

Hanjst Class

Backend Overview

We have switched our default template engine from Smarty to Hanjst for all versions of GWA2.

Regarding to backend or server-side for Hanjst, it is only one task to do. The task in server-side is to output a group of key-value pairs in JSON format to client-side.

This preparation work of JSON can be split into two parts: one is to read all server-side data for business, and the other is to read other embedded template files and output them as common key-value pairs.

Here we have an example of this kind of JSON from server-side. (eg08111102)

{
"innerTpl":"<header class="navi"><a href="/">Homepage</a></header>",
"serverTime":"2019-08-11 01:53:29",
"newsList":[
	{
		"title":"News-Title-1019",
		"id":1019
	},
	{
		"title":"News-Title-2019",
		"id":2019
	}
],
"mod":"news",
"act":"list"
}

A template file looks like this. (eg08111103)

...
<!-- header -->
{$innerTpl}
<!-- header,end -->
<!-- news list -->
<ul>
{foreach $newsList as $n}
	<li>
	{foreach $newsList[$n] as $p}
		<span>{$p}: {$newsList[$n][$p]}</span>
	{/foreach}
	</li>
{foreachelse}
	<li>No data.</li>
{/foreach}
</ul>
<!-- news list, end -->
<div>
	<p>Server Time: {$serverTime}</p>
</div>
....

If all of these work well, we finally generate a pure HTML like this. (eg08111104)

...
<!-- header -->
<header class="navi"><a href="/">Homepage</a></header>
<!-- header,end -->
<!-- news list -->
<ul>
	<li>
		<span>id: 1019</span>
		<span>title: News-Title-1019</span>
	</li>
	<li>
		<span>id: 2019</span>
		<span>title: News-Title-2019</span>
	</li>
</ul>
<!-- news list, end -->
<div>
	<p>Server Time: 2019-08-11 01:53:29</p>
</div>
....

Hanjst Class for Server-side


So for each back-end language, it is mandatory to create a class of methods for Hanjst to cope with JSON data in server-side.

Generally the class has a container, e.g., HashMap, Associative Array, to hold all variables which need to be output at the end of this request.

For instance, in GWA2 Java, a news reader may look like this. (eg08111105)


HashMap output = new HashMap();

//- suppose news is initilized, and Wht
HashMap newList = news.getList();
output.put("newsList", newsList);
output.put("serverTime", Wht.dateFormat((new Date())));

//- suppose hanjst is initilized
String jsonData = hanjst.map2Json(output);
String currentTemplateFile = "index.html";
String jsonDataArea = "HANJST_JSON_DATA";
String templateContent = hanjst.readTemplate(currentTemplateFile);

//- replacements and display
templateContent = templateContent.replace(jsonDataArea, jsonData);
out.println(templateContent);

All of these codes can be found in GWA2 in Java in GitHub.

A simple flow chat shows the process here.

--> End-user fires request

--> Hanjst server-side (eg08111105)  

--> Raw HTML (eg08111102 + eg08111103)

--> Hanjst client-side

--> Final HTML (eg08111104)

--> End-user sees contents

There is a Hanjst.java or Hanjst.class.jsp for Java, and similarly, Hanjst.class.php for PHP, so as to Perl, Python and so on.

  1. Hanjst with GWA2 in Java
  2. Hanjst Demo Page
  3. GWA2 switch from Smarty to Hanjst

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