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Sephiroth

Templating Style in Processwire: Twig Templating

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Hi, So today I will writing a small tutorial on developing templates in Processwire using Twig Template, Processwire is a highly flexible CMS which gives developers/designers/users options and allows easy extension of the platform. So here goes the tutorial 

What is Twig Template ?

Simply put in my own words, Twig is a modern templating engine that compiles down to PHP code, unlike PHP, Twig is clean on the eyes , flexible and also quite *easy* to have dynamic layout site with ease ,without pulling your hair out. Twig is trusted by various platforms. It was created by the guys behind Symfony.

Take this code as an example

{% for user in users %}
    <h1>* {{ user }}</h1>
{% endfor %}

This will simply be the equivalent in PHP World

<?php

$userArray = ["Nigeria","Russia"];

foreach($userArray as $user):
?>
<h1><?= $user ?></h1>
<?php
endforeach;

The PHP code though looks simple enough however, you start to notice that you have to be concerned about the PHP tags by ensuring they are closed  properly , most times projects gets bigger and comes complex and harder to read/grasp, and also in PHP you can explicitly create variables in the template making it very hard to read as it grows and prone to getting messy WordPress is a major culprit when it comes to that regard.

Have you ever wanted to created separate layouts for different pages and  break your sites into different parts e.g Sidebar, Comment Section, Header Section ? the regular approach would be to create individual pages for each section and simply add them as templates for the pages and with time, you can end up having tons of templates, however Twig allows you to easily inherit templates and also override the templates where you can inject content into the block easily. Don't worry if you don't understand the concept, the following parts will explain with an example of how to easily inherit layouts and templates.

Layout

<!DOCTYPE html>
<html lang="en">

<head>
   {{include("layout/elements/header.twig")}}
</head>

<body>
 
    <div class="container-fluid" id="minimal">
        <header id="pageIntro">
            <div class="bio_panel">
                <div class="bio_section col-md-6">
                    <h1>Okeowo Aderemi</h1>
                    <h2>{{ page.body }}</h2>
                </div>
            </div>
            <div class="clearfix"></div>


        </header>
        <section id="page-body">
            <div class="container">
                <div id="intro" class="col-md-7 col-lg-7">
                    <h1>About me</h1>
                    <h2>
                        {{ page.summary }}
                    </h2>
                </div>
              {block name="content"}{/block}
             
                    <a style="font-size:1.799783em; font-style:italic;color:#d29c23" href="{{pages.get('/notes').url }}">Read more articles</a>
                </div>
                <div class="clearfix"></div>
            </div>

        </section>

    </div>
    <footer>
        <div class="header-container headroom headroom--not-top headroom--pinned" id="header-container">

   {{include("layout/elements/footer.twig")}}           

        </div>
    </footer>
</body>

</html>

This is basically a layout where we specify blocks and include other templates for the page, don't panic if you don't understand what is going on, I will simply break down the weird part as follows:

Include

This basically is similar to native PHP 'include', as it's name suggests it simply includes the templates and injects the content into the layout , nothing out of the ordinary here if you are already familiar with php's include function.

{{ output }}

This simply evaluates the expression and prints the value, this  evaluate expressions, functions that return contents , in my own short words it's basically the same as <?= output ?> except for the fact that it's cleaner to read.

{% expression %}

unlike the previous this executes statements such as for loops and other Twig statements.

{% for characters in attack_on_titans %}
<h1> {{characters}} </h1>
                {% endfor %}

This  executes a for loop and within the for loop, it creates a context to which variables in that context can be referenced and evaluated, unlike dealing with the opening and closing PHP tags, Twig simply blends in with markup and makes it really quick to read. 

I will simply post the contents of both the header and footer so you can see the content of what is included in the layout

header.php

<meta charset="utf-8"/>
<meta content="IE=edge" http-equiv="X-UA-Compatible"/>
<meta content="width=device-width, initial-scale=1" name="viewport"/>
<title>
    {{ page.title }}
</title>
<link href=" {{config.urls.templates }}assets/css/bootstrap.min.css" rel="stylesheet"/>
<link href="{{config.urls.templates }}assets/css/main.min.css" rel="stylesheet"/>
<link rel='stylesheet' type='text/css' href='{{config.urls.FieldtypeComments}}comments.css' />
<link rel="stylesheet" href="{{config.urls.siteModules}}InputfieldCKEditor/plugins/codesnippet/lib/highlight/styles/vs.css">
<script type="text/javascript" src="{{config.urls.siteModules}}InputfieldCKEditor/plugins/codesnippet/lib/highlight/highlight.pack.js"></script>

<script src="{{config.urls.templates }}assets/js/vendors/jquery-1.11.3.min.js">
</script>
<script src="{{config.urls.templates }}assets/js/vendors/bootstrap.min.js">
</script>
<script src="{{config.urls.FieldtypeComments}}comments.js"></script>
<link rel="stylesheet" type='text/css' href="{{config.urls.templates}}js/jquery.fancybox.min.css">
 <script src="{{config.urls.templates}}js/jquery.fancybox.min.js"></script>
 {block name="javascriptcodes"}{/block}

footer.php

 <nav class="site-nav pull-right">
                <div class="trigger">
                    <a class="page-link" href="{{pages.get('/about').url}}">
                        <span>{</span> About
                        <span>}</span>
                    </a>
                    <a class="page-link" href="{{pages.get('/notes').url}}">
                        <span>{</span> Journals
                        <span>}</span>
                    </a>
               
                    <a class="page-link" target="_blank" href="https://ng.linkedin.com/in/okeowo-aderemi-82b75730">
                        <span>{</span> Linkedin
                        <span>}</span>
                    </a>
                    <a class="twitter page-link" target="_blank" href="https://twitter.com/qtguru">
                        <span>{</span> Twitter
                        <span>}</span>

                    </a>
                </div>
            </nav>

There's nothing special here, other than twig simply injecting these fragments into the main layout , the next part is the most interesting and important concept and benefit that Twig has to offer

{% block content %}{% endblock %}

This tag simply creates a placeholder in which the content would be provided by the template inheriting this layout, in lay terms it simply means child templates will provide content for that block, the 'content' simply uses the name 'content' to refer to that specific block, so assuming we were to inherit this template it would simply look like this.

Inheriting Template Layout

{% extends 'layout/blog.twig' %}
{% block content %}
<div class="container blog-container">
    <section class="blog">
        <header class="blog-header">
            <h1>
                {{page.title}}
            </h1>
            <h5 class="blog_date">
                {{page.published|date("F d, Y")}} 
            </h5>
            <br>
            </br>
        </header>
        <div class="blog_content">
            <hr class="small" />
             {{page.body}}
             <hr class="small" />

        </div>
    </section>
</div>
{% endblock %}

{% block nav %}
 <div class="col-md-4 col-xs-4 col-sm-4 prev-nav">
                        <a href="{{page.prev.url}}">
                            ← Prev
                        </a>
                    </div>
                    <div class="col-md-4 col-xs-4 col-sm-4 home-nav">
                        <a href="{{homepage.url}}">
                            Home
                        </a>
                    </div>
                    <div class="col-md-4 col-xs-4 col-sm-4 next-nav">
                        <a href="{{page.next.url}}">
                            Next →
                        </a>
                    </div>
{% endblock %}

In this snippet you can easily notice how each blocks previously created in the header and layout are simply referenced by their names, by now you will notice that twig doesn't care how you arrange the order of each block, all Twig does is to get the contents for each blocks in the child templates and inject them in the layout theme, this allows flexible templating and also extending other layouts with ease.

Twig in Processwire

Thanks to @Wanze we have a Twig Module for Processwire and it's currently what i use to build PW solutions to clients

https://modules.processwire.com/modules/template-engine-twig/

The Modules makes it easy to not only use Twig in PW but also specify folders to which it reads the twig templates, and also injects Processwire objects into it, which is why i can easily make reference to the Pages object, another useful feature in this module is that you can use your existing template files to serve as the data provider which will supply the data to be used for twig template.

take for example, assuming I wanted the homepage to display the top six blog posts on it, TemplateEngineTwig will simply load the home.php ( Depending on what you set as the template), it is also important that your twig file bears the same name as your template name e.g home.php will render into home.twig here is an example to further explain my point.

home.php

<?php
 
  //Get the Top 6 Blog Posts
  $found=$pages->find("limit=6,include=hidden,template=blog-post,sort=-blog_date");
  $view->set("posts",$found);

 

The $view variable is the TemplateEngine which in this case would be Twig, the set method simply creates a variables posts which holds the data of the blog posts, the method allows our template 'blog.twig' to simply reference the 'posts' variable in Twig Context. Here is the content of the 'blog.twig' template

blog.tpl

{% extends 'layout/blog.twig' %}
{% block content %}
   <div class="block_articles col-md-5 col-lg-5">
                    {% for post in posts %}
                    <div class="article_listing">
                        <span class="article_date"> {{post.published}}</span>
                        <h2 class="article_title">
                            <a href="{{post.url}}">{{post.title}}</a>
                        </h2>
                    </div>
		{% endfor %}
{% endblock %}

So home.php sets the data to be used in home.tpl once Twig processes the templates and generates the output, twig takes the output from the block and injects it in the appriopriate block in the layout, this makes Processwire templating more flexible and fun to work with. 

The major advantage this has; is that you can easily inherit layouts and provide contents for them with ease, without the need of running into confusions when handling complex layout issues,an example could be providing an administrator dashboard for users on the template side without allowing users into the Processwire back-end. You can also come up with several layouts and reusable templates.

 

Feel free to ask questions and any concerns  in this approach or any errors I might have made or overlooked.

Thanks

 

 

 

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Pls tell us, what is the advantage of twig templating over pure php and using the delayed output strategy with markup regions?

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I'm not using twig but latte but the main advantages are sophisticated template inheritence, filters, reusable blocks/partials, etc, and after all, more readable and maintainable code. Backdraws are the small overhead and some extra complexity, of course the latter disappears when you get used to it.

Markup regions is in my opinion a very simple templating implementation. This works fine if you don't need any of those extra features, and in case of template engines you can more easily find help if you are stuck.

Speaking of myself, I made only my first PW project with pure PHP about 3 years ago, then all with latte.

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6 hours ago, pideluxe said:

Pls tell us, what is the advantage of twig templating over pure php and using the delayed output strategy with markup regions?

"delayed output strategy" to me is the same as concatenation, it easily gets messy, hard and difficult to follow, not exactly easy to inherit templates or layouts.

It might work but it comes at the cost of readability and how easy it is in making mistakes.

 Twig Template makes it easier to read ,the only disadvantage I can bring up is that, you cannot instantiate a class inside the template, you must pass a reference of an object to it, then again, your template must not be tied to a code, it should simply take a value it expects and evaluate from that. It makes things really easy to read. 

As for performance it compiles down to php templates, it only compiles when the source has been changed. 

 

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6 hours ago, tpr said:

I'm not using twig but latte but the main advantages are sophisticated template inheritence, filters, reusable blocks/partials, etc, and after all, more readable and maintainable code. Backdraws are the small overhead and some extra complexity, of course the latter disappears when you get used to it.

Markup regions is in my opinion a very simple templating implementation. This works fine if you don't need any of those extra features, and in case of template engines you can more easily find help if you are stuck.

Speaking of myself, I made only my first PW project with pure PHP about 3 years ago, then all with latte.

I just looked at Latte and it's very clean to read, it looks so similar to Twig, I was using Smarty before but Twig is 100% OOP and extending it is cleaner compared to Smarty, I will give Natte Latte a shot later on. 

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5 hours ago, Sephiroth said:

"delayed output strategy" to me is the same as concatenation

Delayed output is not about concatenation but storing rendered html in a variable to be output later on. Eg:

<?php
$output = wireRenderFile("./partials/partial.php", array('page' => $page));
//lost of other code :)
echo $output;

Ryan prefers concatenation to wireRenderFile. I prefer wireRenderFile to concatenation, for example.

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I used delayed output and markup regions to make clear, they are just other concepts of templating (engines). Delayed output-strategy is about inheritance and markup regions are the so called blocks in twig. Templating in other languages/engines than php is about using other syntax and replacing php-tags with something else, e.g. {%...%} for twig... 

And for terms of reusability: If you are using different fields, you cannot reuse your twig-files, or am i missing something here?

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Twig doesn't know what a field is, all it expects are variables which are passed to the twig templates from the processwire php files based on the Twig module. Let's take for example the side template in twig, I can have an array of posts which will render the post in a list manner. All I simply need to do is get a list of post and set it with a variable name for that template and the twig template simply renders it based on the variable passed. Besides at the end of the day Twig is basically still compiles to php so it's nothing unique just another layer. 

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On 3/6/2018 at 9:09 PM, Sephiroth said:

{block name="content"}{/block}

Hello Sephiroth,

Thank you for your tutorial, it is very precious although this code above does not work for me.
I had

{% block content %}
{% endblock %}

which had no problems but did not display the block content.

Thank you for any help.

 

Sten

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On 6/10/2018 at 8:42 AM, Sten said:

Hello Sephiroth,

Thank you for your tutorial, it is very precious although this code above does not work for me.
I had

{% block content %}
{% endblock %}

which had no problems but did not display the block content.

Thank you for any help.

 

Sten

{block name="content"}{/block}

Sorry about that, that was a smarty template, my brain went into Smarty mode the correct syntax is what you provided, in your layout where you arr inheritting from, ensure you have something like this 
 

{%  block content %} {%  endblock %}

 

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      {# components/sections.twig #} {% for section in page.sections %} {% set template = 'sections/section--' ~ section.type ~ '.twig' %} {{ include( [template, 'sections/section.twig'], { section: section }, with_context = false ) }} {% endfor %} Note that the array syntax in the include function tells Twig to render the first template that exists. So for a section called downloads, it will look look for the template sections/section--downloads.twig and fallback to the generic sections/section.twig. The generic section template will only include the fields that are common to all sections. In my case, each section will have a headline (section_headline) and a select field to choose a background colour (section_background) :
      {# sections/section.twig #} {% set section_classes = [ 'section', section.type ? 'section--' ~ section.type, section.section_background.first.value ? 'section--' ~ section.section_background.first.value ] %} <div class="{{ section_classes|join(' ')|trim }}"> <section class="container"> {% block section_headline %} {% if section.section_headline %} <h2 class="section__headline">{{ section.section_headline }}</h2> {% endif %} {% endblock %} {% block section_content %} {{ section.type }} {% endblock %} </section> </div> This section template generates classes based on the section type and background colour (for example: section section--downloads section--green) so that I can add corresponding styling with CSS / SASS. The specific templates for each section will extend this base template and fill the block section_content with their custom markup. For example, for our downloads section (assuming it contains a multivalue files field download_files):
      {# sections/section--download.twig #} {% extends "sections/section.twig" %} {% block section_content %} <ul class="downloads"> {% for download in section.download_files %} <li class="downloads__row"> <a href="{{ download.file.url }}" download class="downloads__link"> {{ download.description ?: download.basename }} </a> </li> {% endfor %} </ul> {% endblock %} It took some setup, but now every section needs only care about their own unique fields and markup without having to include repetitive boilerplate markup. And it's still completely extensible: If you need, for example, a full-width block, you can just not extend the base section template and get a clean slate. Also, you can always go back to the base template and add more blocks as needed, without having to touch all the other sections. By the way, you can also extend the base section template from everywhere you want, not only from repeater matrix types.
      Now we only need to include the sections component inside the page template
      {# pages/page.twig #} {% block content %} {% if page.hasField('sections') and page.sections.count %} {{ include('components/sections.twig' }} {% endif %} {% endblock %} Conclusion
      This first part was mostly about a clean environment setup and template structure. By now you've probably got a good grasp on how I organize my twig templates into folders, depending on their role and importance:
      blocks: This contains reusable blocks that will be included many times, such as a responsive image block or a link block. components: This contains special regions such as the header and footer that will probably be only used once per page. sections: This will contain reusable, self-contained sections mostly based on the Repeater Matrix types. They may be used multiple times on one page. pages: High-level templates corresponding to ProcessWire templates. Those contain very little markup, but mostly include the appropriate components and sections. Depending on the size of the project, you could increase or decrease the granularity of this as needed, for example by grouping the sections into different subfolders. But it's a solid start for most medium-sized projects I tackle.
      Anyway, thanks for reading! I'll post the next part in a couple of days, where I will go over how to add more functionality into your environment in a scalable and reusable way. In the meantime, let me know how you would improve this setup!
    • By MoritzLost
      This is part two of my tutorial on integrating Twig in ProcessWire sites. As a reminder, here's the table of contents:
      Part 1: Extendible template structures How to initialize a custom twig environment and integrate it into ProcessWire How to build an extendible base template for pages, and overwrite it for different ProcessWire templates with custom layouts and logic How to build custom section templates based on layout regions and Repeater Matrix content sections Part 2: Custom functionality and integrations How to customize and add functionality to the twig environment How to bundle your custom functionality into a reusable library Thoughts on handling translations A drop-in template & functions for responsive images as a bonus Make sure to check out part one if you haven't already! This part will be less talk, more examples, so I hope you like reading some code 🙂
      Adding functionality
      This is more generic Twig stuff, so I'll keep it short, just to show why Twig is awesome and you should use it! Twig makes it super easy too add functions, filters, tags et c. and customize what the language can do in this way. I'll show a couple of quick examples I built for my projects.
      As a side note, I had some trouble with functions defined inside a namespace that I couldn't figure out yet. For the moment, it sufficed to define the functions I wanted to use in twig inside a separate file in the root namespace (or, as shown further below, put all of it in a Twig Extension). If you want a more extensible, systematic approach, check out the next section (going further).
      Link template with external target detection
      This is a simple template that builds an anchor-tag (<a>) and adds the necessary parameters. What's special about this is that it will automatically check the target URL and include a target="_blank" attribute if it's external. The external URL check is contained in a function:
      // _functions.php /** * Finds out whether a url leads to an external domain. * * @param string $url * @return bool */ function urlIsExternal(string $url): bool { $parser = new \League\Uri\Parser(); [ 'host' => $host ] = $parser->parse($url); return $host !== null && $host !== $_SERVER['HTTP_HOST']; } // _init.php require_once($config->paths->templates . '_functions.php'); // don't forget to add the function to the twig environment $twig_env->addFunction(new \Twig\TwigFunction('url_is_external', 'urlIsExternal')); This function uses the excellent League URI parser, by the way. Now that the function is available to the Twig environment, the link template is straightforward:
      {# # Renders a single anchor (link) tag. Link will automatically # have target="_blank" if the link leads to an external domain. # # @var string url The target (href). # @var string text The link text. Will default to display the URL. # @var array classes Optional classes for the anchor. #} {%- set link_text = text is not empty ? text : url -%} <a href="{{ url }}" {%- if classes is not empty %} class="{{ classes|join(' ') }}"{% endif %} {%- if url_is_external(url) %} target="_blank"{% endif %}> {{- link_text -}} </a> String manipulation
      A couple of functions I wrote to generate clean meta tags for SEO, as well as valid, readable IDs based on the headline field for my sections.
      /** * Truncate a string if it is longer than the specified limit. Will append the * $ellipsis string if the input is longer than the limit. Pass true as $strip_tags * to strip all markup before measuring the length. * * @param string $text The text to truncate. * @param integer $limit The maximum length. * @param string|null $ellipsis A string to append if the text is truncated. Pass an empty string to disable. * @param boolean $strip_tags Strip markup from the text? * @return string */ function str_truncate( string $text, int $limit, ?string $ellipsis = ' …', bool $strip_tags = false ): string { if ($strip_tags) { $text = strip_tags($text); } if (strlen($text) > $limit) { $ell_length = $ellipsis ? strlen($ellipsis) : 0; $append = $ellipsis ?? ''; $text = substr($text, 0, $limit - ($ell_length + 1)) . $append; } return $text; } /** * Convert all consecutive newlines into a single space character. * * @param string $text The text to convert. */ function str_nl2singlespace( string $text ): string { return preg_replace( '/[\r\n]+/', ' ', $text ); } /** * Build a valid html ID based on the passed text. * * @param string $title * @return string */ function textToId(string $title): string { return strtolower(preg_replace( [ '/[Ää]/u', '/[Öö]/u', '/[Üü]/u', '/ß/u', '/[\s._-]+/', '/[^\w\d-]/', ], [ 'ae', 'oe', 'ue', 'ss', '-', '-', ], $title )); } // again, add those functions to the twig environment $twig_env->addFilter(new \Twig\TwigFilter('truncate', 'str_truncate')); $twig_env->addFilter(new \Twig\TwigFilter('nl2ss', 'str_nl2singlespace')); $twig_env->addFilter(new \Twig\TwigFilter('text_to_id', 'textToId')); Example usage for SEO meta tags:
      {% if seo.description %} {% set description = seo.description|truncate(150, ' …', true)|nl2ss %} <meta name="description" content="{{ description }}"> <meta property="og:description" content="{{ description }}"> {% endif %} instanceof for Twig
      By default, Twig doesn't have an equivalent of PHP's instanceof keyword. The function is super simple, but vital to me:
      // instanceof test for twig // class must be passed as a FQCN with escaped backslashed $twig_env->addTest(new \Twig\TwigTest('instanceof', function ($var, $class) { return $var instanceof $class; })); In this case, I'm adding a TwigTest instead of a function. Read up on the different type of extensions you can add in the documentation for Extending Twig.
      Note that you have to use double backslashes to use this in a Twig template:
      {% if og_img is instanceof('\\Processwire\\Pageimages') %} Going further: custom functionality as a portable Twig extension
      Most of the examples above are very general, so you'll want to have them available in every project you start. It makes sense then to put them into a single library that you can simply pull into your projects with git or Composer. It's really easy to wrap functions like those demonstrated above in a custom Twig extension. In the following example, I have wired the namespace "moritzlost\" to the "src" folder (see my Composer + ProcessWire tutorial if you need help with that):
      // src/MoritzFuncsTwigExtension.php <?php namespace moritzlost; use Twig\Extension\AbstractExtension; use Twig\TwigFunction; use Twig\TwigFilter; use Twig\TwigTest; class MoritzFuncsTwigExtension extends AbstractExtension { // import responsive image functions use LinkHelpers; public function getFunctions() { return [ new TwigFunction('url_is_external', [$this, 'urlIsExternal']), ]; } public function getFilters() { return [ new TwigFilter('text_to_id', [$this, 'textToId']), ]; } public function getTests() { return [ new TwigTest('instanceof', function ($variable, string $namespace) { return $variable instanceof $namespace; }), ]; } } // src/LinkHelpers.php <?php namespace moritzlost; trait LinkHelpers { // this trait contains the textToId and urlIsExternal methods // see the section above for the full code } Here I'm building my own class that extends the AbstractExtension class from Twig. This way, I can keep boilerplate code to a minimum. All I need are public methods that return an array of all functions, filters, tests et c. that I want to add with this extension. As is my custom, I've further split the larger functions into their own wrapper file. In this case, I'm using a trait to group the link-related functions (it's easier this way, since classes can only extend one other class, but use as many traits as they want to).
      Now all that's left is to add an instance of the extension to our Twig environment:
      // custom extension to add functionality $twig_env->addExtension(new MoritzFuncsTwigExtension()); Just like that we have a separate folder that can be easily put under version control and released as a micro-package that can then be installed and extended in other projects.
      Translations
      If you are building a multi-language site, you will need to handle internationalization of your code. ProcessWire can't natively handle translations in Twig files, so I wanted to briefly touch on how to handle this. For a recent project I considered three approaches:
      Build a module to add twig support to ProcessWire's multi-language system. Use an existing module to do that. Build a custom solution that bypasses ProcessWire's translation system. For this project, I went with the latter approach; I only needed a handful of phrases to be translated, as I tend to make labels and headlines into editable page fields or use the field labels themselves, so there are only few translatable phrases inside my ProcessWire templates. But the beauty of ProcessWire is that you can build your site whatever way you want. As an example, here's the system I came up with.
      I used a single Table field (part of the ProFields module) with two columns: msgid (a regular text field which functions as a key for the translations) and trans (a multi-language text field that holds the translations in each language). I added this field to my central settings page and wrote a simple function to access individual translations by their msgid:
      /** * Main function for the translation API. Gets a translation for the msgid in * the current language. If the msgid doesn't exist, it will create the * corresponding entry in the settings field (site settings -> translations). * In this case, the optional second parameter will be used as the default * translation for this msgid in the default language. * * @param string $msgid * @param ?string $default * @return string */ function trans_api( string $msgid, ?string $default = null ): string { // this is a reference to my settings page with the translations field $settings = \Processwire\wire('config')->settings; $translations = $settings->translations; $row = $settings->translations->findOne("msgid={$msgid}"); if ($row) { if ($row->trans) { return $row->trans; } else { return $msgid; } } else { $of = $settings->of(); $settings->of(false); $new = $translations->makeBlankItem(); $new->msgid = $msgid; if ($default) { $default_lang = \Processwire\wire('languages')->get('default'); $new->trans->setLanguageValue($default_lang, $default); } $settings->translations->add($new); $settings->save('translations'); $settings->of($of); return $default ?? $msgid; } } // _init.php // add the function with the key "trans" to the twig environment $twig_env->addFunction(new \Twig\TwigFunction('trans', 'trans_api')); // some_template.twig // example usage with a msgid and a default translation {{ trans('detail_link_label', 'Read More') }} This function checks if a translation with the passed msgid exists in the table and if so, returns the translation in the current language. If not, it automatically creates the corresponding row. This way, if you want to add a translatable phrase inside a template, you simply add the function call with a new msgid, reload the page once, and the new entry will be available in the backend. For this purpose, you can also add a second parameter, which will be automatically set as the translation in the default language. Sweet.
      While this works, it will certainly break (in terms of performance and user-friendliness) if you have a site that required more than a couple dozen translations. So consider all three approaches and decide what will work best for you!
      Bonus: responsive image template & functions
      I converted my responsive image function to a Twig template, I'm including the full code here as a bonus and thanks for making it all the way through! I created a gist with the extension & and template that you can drop into your projects to create responsive images quickly (minor warning: I had to adjust the code a bit to make it universal, so this exact version isn't properly tested, let me know if you get any errors and I'll try to fix it!). Here's the gist. There's a usage example as well. If you don't understand what's going on there, make sure to read my tutorial on responsive images with ProcessWire.
      Conclusion
      Including the first part, this has been the longest tutorial I have written so far. Again, most of this is opinionated and influenced by my own limited experience (especially the part about translations), so I'd like to hear how you all are using Twig in your projects, how you would improve the examples above and what other tips and tricks you have!
    • By modifiedcontent
      I had upgraded my Apache configuration to include PHP7.2 and PHP7.3 for a Laravel-based script on the same server. Somehow it/I messed up a previously fine Processwire site, in a very confusing way.
      The site still looks fine, but editing template files has no effect whatsoever. It is stuck on some kind of cached version. I have already disabled PHP7's OPcache, cleared browser caches, etc, with no effect.
      The pages now apparently come from PW's assets/cache/FileCompiler folder, even though I never enabled template caching for this site.
      I have tried adding "namespace ProcessWire;" to the top of the homepage template file, but then I get this fatal error:
      My functions.php file pulls data in from another Processwire installation on the same VPS with the following line:
      $othersitedata = new ProcessWire('/home/myaccount/public_html/myothersite/site/', 'https://myothersite.com/'); That apparently still works fine; the site still displays data from the other installation, but via the "cached" template that I am now unable to change.
       
      I don't know where to start with this mess. Does any of this sound familiar to anyone? Any pointers in the right direction would be much appreciated. 
       
      Edit:
      Adding "$config->templateCompile = false;" to config.php results in the same fatal error as above. 
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