From Cash Costello's Elgg 1.8 Social Networking page 287 under What template engine is used? he says, 'Elgg uses PHP as its template engine.'
What exactly is meant by a Template Engine?
Full extract:
What template engine is used?
Elgg uses PHP as its template engine. This results in a flexible view system since the full power of PHP is available. Developers also do not have to learn a new template language to use Elgg as they would with an engine like Smarty. On the downside, an expressive template language such as PHP is a temptation to mix controller code into the views.
A template (in this context) is an HTML file whose contents are dynamically filled in to produce the final page you're seeing. There are myriads of ways how this "dynamic filling in" can happen, from specialised XML transformation syntaxes to DOM manipulators. "PHP as a template engine" just means that they're using PHP as it was designed: embedded PHP snippets inside of HTML.
If you only know PHP, it may seem strange to you that this needs specific mention. Other languages are not designed to be embeddable inside other languages, so templating is a bit more of a complex task and usually calls for special "templating engines". Such things are becoming more popular in PHP as well though, mostly because their syntax can be simpler and more manageable and they enforce separation of concerns better.
For example, compare to Twig.
Related
Using Node.js and express in a MEAN environment, I am looking for a simple and straightforward template engine, meeting these requirements:
does not dictate me to only use its own weird syntax but allows me to keep writing webpages using pure/plain html and js
supports conditional includes
works with express
operates on server-side (Node.js/Express)
executes freakin' fast ;)
Basically I just want to slice my webpage into several modules (e. g. header, footer, ...) and include those now and then based on simple conditions. I don't want to entirely (re-)rebuild all webpages using a proprietary template language but rather prepare a few html modules that I concatenate at runtime (comparable to PHP where I just use the include instruction to paste prepared html code).
I had a look at http://garann.github.io/template-chooser/ and https://github.com/nodejs/node-v0.x-archive/wiki/modules#templating but the sites seem outdated and according to them, there ain't no template engine available fully meeting my requirements!?
Suggestions anyone?
I think ejs is more natural for what you are looking for https://scotch.io/tutorials/use-ejs-to-template-your-node-application, but jade can work also. The example in the link uses partials, which you dont need to use if ur just rendering a single page
I come from a PHP background and I've used frameworks such as CakePHP and Laravel and it is quite easy to work with layouts and views in all of them.
And the possibility of using PHP inside those template engines provide a way to do things such as:
<?php for($i=0; $i<1000; $i++){ ?>
<td>demo</td>
<? } ?>
Now, starting with Node and express.js I found out template engines seems quite basic here. I've tried hjs, hogan, swig, mustache, handlebars... none of them offers both :
Layout support (templates and views)
A way to do loops like the one I named before.
Am I missing something? Am I asking for too much?
Which one would you recommend me?
A lot of the template engines for Javascript take the philosophical view that it's better to enforce a fairly strict separation between logic and presentation, meaning that the complexity of code/logic allowed in the template is deliberately limited. For a quick overview of this topic, see http://blog.startifact.com/posts/older/the-new-hot-thing-in-web-development-client-side-templating-languages.html (it's about client-side templating, but since it's Javascript, a lot of those same template languages are the ones popular in node.js / Express). This idea of logicless templates exists in the PHP world as well, it's just not as common.
For a more academic treatment of this subject, see this paper: http://www.cs.usfca.edu/~parrt/papers/mvc.templates.pdf. (The author is also the author of a popular template engine for Java called StringTemplate.) The author makes a lot of good points, and in general I agree with the idea of logicless templates, but there are times when it can be inconvenient and I find myself more on the fence about it...see this link for some further considerations. Obviously there are also those who want to be able to anything from a template (as you can in PHP) and believe it's fine to rely on the self-restraint of the programmer not to put too much code in the view, which is where template engines like EJS come in.
Having said all that, it's important to note that what you want to achieve is possible in Handlebars (which is one of the "logicless" languages) and probably many of the others you tried as well. To do it in Handlebars, you'd need to create a custom helper. This might be what you're looking for:
https://www.npmjs.org/package/handlebars-helper-repeat
Example usage:
{{#repeat 10}}
{{> button }}
{{/repeat}}
You could also extend it to be able to support arguments to be able to control the starting number or increment, although that would probably be getting into logic that might be better done in the JS code (according to the Handlebars philosophy) while preparing the data for the template.
With regard to layouts, the closest thing in Handlebars (which is the template engine I'm most familiar with) is partials. This link provides a good introduction to those: http://blog.teamtreehouse.com/handlebars-js-part-2-partials-and-helpers.
Personally I'm a big fan of the template language in an awesome framework (built on Express) called Derby. Its template language is similar to Handlebars, but comes with a couple of handy extensions - just enough to make it a bit more convenient to use without allowing too much logic to creep into the template. Unfortunately I don't think there's a standalone version of it (i.e. you have to use the full Derby framework), but you could create custom helpers in Handlebars to achieve a similar effect.
I'm relatively new to Expression Engine, and as I'm learning it I am seeing some stuff missing that WordPress has had for a while. A big one for me is shortcodes, since I will use these to allow CMS users to place more complex content in place with their other content.
I'm not seeing any real equivalent to this in EE, apart from a forthcoming plugin that's in private beta.
As an initial test I'm attempting to fake shortcodes by using delimited strings (e.g. #foo#) in the content field, then using a regex to pull those out and pass them to a function that can retrieve the content out of EE's database.
This brings me to a second question, which is that in looking at EE's API docs, there doesn't appear to be a simple means of retrieving the channel entries programmatically (thinking of something akin to WP's built-in get_posts function).
So my questions are:
a) Can this be done?
b) If so, is my method of approaching it reasonable? Or is there something stupidly obvious I'm missing in my approach?
To reiterate, my main objective here is to have some means of allowing people managing content to drop a code in place in their content that will be replaced with channel content.
Thanks for any advice or help you can give me.
Here's a simple example of the functionality you're looking for.
1) Start by installing Low Replace.
2) Create two Global Variables called gv_hello and gv_goodbye with the values "Hello" and "Goodbye" respectively.
3) Put this text into the body of an entry:
[say_hello]
Nice to see you.
[say_goodbye]
4) Put this into your template, wrapping the Low Replace tag around your body field.
{exp:low_replace
find="[say_hello]|[say_goodbye]"
replace="{gv_hello}|{gv_goodbye}"
multiple="yes"
}
{body}
{/exp:low_replace}
5) It should output this into your browser:
Hello
Nice to see you.
Goodbye
Obviously, this is a really simple example. You can put full blown HTML into your global variable. For example, we've used that to render a complex, interactive graphic that isn't editable but can be easily dropped into a page by any editor.
Unfortunately, due to parse order issues, EE tags won't work inside Global Variables. If you need EE tags in your short code output, you'll need to use Low Variables addon instead of Global Variables.
Continued from the comment:
Do you have examples of the kind of shortcodes you want to support/include? Because i have doubts if controlling the page-layout from a text-field or wysiwyg-field is the way to go.
If you want editors to be able to adjust layout or show/hide extra parts on the page, giving them access to some extra fields in the channel, is (imo) much more manageable and future-proof. For instance some selectfields, a relationship (or playa) field, or a matrix, to let them choose which parts to include/exclude on a page, or which entry from another channel to pull content from.
As said in the comment: i totally understand if you want to replace some #foo# tags with images or data from another field (see other answers: nsm-transplant, low_replace). But, giving an editor access to shortcodes and picking them out, is like writing a template-engine to generate ee-template code for the ee-template-engine.
Using some custom fields to let editors pick and choose parts to embed is, i think, much more manageable.
That being said, you could make a plugin to parse the shortcodes from a textareas content, and then program a lot, to fetch data from other modules you want to support. For channel entries you could build out of the channel data library by objectiveHTML. https://github.com/objectivehtml/Channel-Data
I hear you, I too miss shortcodes from WP -- though the reason they work so easily there is the ubiquity of the_content(). With the great flexibility of EE comes fewer blanket solutions.
I'd suggest looking at NSM Transplant. It should fit the bill for you.
There is also a plugin called Shortcode, which you can find here at
Devot-ee
A quote from the page:
Shortcode aims to allow for more dynamic use of content by authors and
editors, allowing for injection of reusable bits of content or even
whole pieces of functionality into any field in EE
I am creating a Multilingual web site and I use a resource manager for each language.
when user select a language all pages use the selected resource bondles.
as entire sites only is available in one language,how search engines crawl the other languages ?
or does search engine crawl optional provided languages ?
As you know, when you have a static multilingual website that has separate page for each language, you don't have any problem with search engines. Whereas, each page has an unique url.
But in dynamic applications, you don't have separate page for each language and have to use resource instead, you can add a new language or remove an already existing language and so on.
Therefore, we have to use Url Rewriter/Routing for generating unique url for each language. Check the following example out.
Suppose we have a webform in the following url and our application supports two languages (e.g. English United States en-US, English Great Britain en-GB).
www.domain.com/home.aspx
There are some problems, we have permanent url for all of languages. Thus, search engines will be index the default language anyway. The solution is simple, you have to generate separate url for each language by using Url Rewriter/Routing as follows.
www.domain.com/{country}/{language}/home.aspx
Afterwards, you have to inference the specified culture name from the above url and set the current Culture and UICulture properties. Thus, the requested page will be shown in desired language.
The sitemap should be generate programmatically and uses the same way as above, in this case.
www.domain.com/{country}/{language}/sitemap.xml
You have to inference the specified culture from the above url and generate sitemap dependent on culture. To introduce available sitemaps to the search engines you have to use robots.txt that should be generate programmatically as well.
you might be using cookies/sessions for remembering selected language, right?
Neither of them affects search engine. They simply ignore cookies. However, If u rely on session variable for remembering selected language, in the absence of cookies each time new session will be created canceling the language selection.
Ankit
as part of our application i need to build component that will output code in php and asp
that have the same functionality ( and maybe latter jsp ) .
how can i design this kind of component to be generic as possible ?
You need to be able to create a parse tree out of all input languages.
For each output language, you will need to create a set of tree transforming grammar.
You may also require a runtime library to help translate routines that are not available in your output language.
I would personally go with the Strategy Pattern. You could have a master code maker class and instantiate it with a strategy.
PHPCodeStrategy
ASPCodeStrategy
Then each would have a method called execute maybe. Bu then you could add further strategies down the line and extend your application.
Andrew