Where to hook in to alter View output in Laravel 5? - php

For some kind of output filter, I need to access the final rendered output string that includes both view data as well as 'hardcoded' text in the view file.
For example:
welcome.blade.php
<div>This is bad and you are {{ $variable }}</div>
controller, composer, or something else that attaches variables
view()->with('variable', 'bad')
The final output would be
<div>This is bad and you are bad</div>
But now let's pretend we want to replace each instance of 'bad' with 'good', so we get:
<div>This is good and you are good</div>
Altering view data is well supported, but how to apply some altering logic to the fully rendered content? (since I think this is the only way to also alter contents of a view file itself?)
Note: if and only if possible, I'd prefer a 'hook-in' solution instead of an 'extend-core' one..

Take a look at the CompilerEngine (Illuminate\View\Engines\CompilerEngine).
You could use it to get the evaluated contents of a view by using the get method.
Maybe combine that with a registered ServiceProvider to manipulate the views content. Also check out the BladeCompiler maybe you can combine those.
But trying to change hardcoded text seems a bit odd. Why not just use variables in the first place. I mean why is it hardcoded if you want to change it afterwards?

Related

is this a good practice to output html using php? [duplicate]

I have been designing websites for a while now, but there is one thing that I have never been quite sure of when using PHP and HTML. Is it better to have the whole document in PHP and echo HTML like so:
<?php
doSomething();
echo "<div id=\"some_div\">Content</div>";
?>
Or have a HTML file like so and just add in the PHP:
<html>
<body>
<?php doSomething(); ?>
<div id="some_div">Content</div>
</body>
</html>
It seems tidier to echo HTML, especially if lots of PHP gets used throughout the page, but doing so loses all formatting of the HTML i.e. colors in the IDE etc.
There are varying opinions on this. I think there are two good ways:
Use a templating engine like Smarty that completely separates code and presentation.
Use your second example, but when mixing PHP into HTML, only output variables. Do all the code logic in one block before outputting anything, or a separate file. Like so:
<?php $content = doSomething();
// complex calculations
?>
<html>
<body>
<?php echo $content; ?>
<div id="some_div">Content</div>
</body>
</html>
Most full-fledged application frameworks bring their own styles of doing this; in that case, it's usually best to follow the style provided.
I think this would depend on your group's or your own decided convention. And it can and should vary depending on what type of file you're working in. If you follow the MVC pattern then your views should be the latter. If you're writing a class or some non-output script/code then you should use the former.
Try to keep a separation of display or formatting of output and the logic that provides the data. For instance let's say you need to make a quick page that runs a simple query and outputs some data. In this case (where there is no other existing infrastructure or framework) you could place the logic in an include or in the top or the bottom of the file. Example:
<?php
# define some functions here that provide data in a raw format
?>
<html>
<body>
<?php foreach($foo = data_function($some_parameter) as $key => $value): ?>
<p>
<?=$value;?>
</p>
<?php endforeach; ?>
</body>
</html>
Or you could place the logic and function definitions in an include file or at the bottom of the file.
Now if you're producing some sort of class that has output (it really shouldn't) then you would echo the HTML or return it from the method being called. Preferably return it so that it can be output whenever and however the implementer would like.
The syntax highlighting is an important benefit of the second method, as you said. But also, if you're following good practices where logic and presentation are separated, you will naturally find that your files that contain HTML are almost entirely HTML, which then, naturally, leads to your second method again. This is the standard for MVC frameworks and the like. You'll have a bunch of files that are all PHP, doing logic, and then when that's done they'll include a presentation file which is mostly HTML with a sprinkling of PHP.
Simple:
More PHP - close HTML in PHP. When you generate HTML code in PHP, when you are doing something like a class, so it is better to make it in echo.
Less PHP - close PHP in HTML. This is stuff like just putting vars into fields of HTML stuff, like forms... And such.
The best approach is to separate the HTML from the PHP using template system or at least some kind of HTML skeleton like:
<main>
<header/>
<top-nav/>
<left-col>
<body />
</left-col>
<right-col />
<footer/>
</main>
Each node represents a template file e.g. main.php, hrader.php and so on. Than you have to separate the PHP code from the templates as something like functions.php and fineally use your second approach for template files and keeping functions clean of "echos" and HTML.
If you can, use a template engine instead.
Although it is slightly easier at first to mix your HTML and PHP, separating them makes things much easier to maintain later on.
I would recommend checking out TemplateLite which is based on Smarty but is a little more light weight.
I've reached a conclusion that using views in MVC framework e.g. Laravel, Yii, CodeIgniter is the best approach even if you are not displaying the html straight away.
Inside the view do all the echoing and looping of prepared variables, don't create or call functions there, unless formatting existing data e.g. date to specific format date('Y-m-d', strtodate(123456789)). It should be used only for creating HTML, not processing it. That's what frameworks have controllers for.
If using plain PHP, create you own view function to pass 3 variables to - html file, array of variables, and if you want to get output as string or print it straight away for the browser. I don't find a need for it as using frameworks is pretty much a standard. (I might improve the answer in the future by creating the function to get view generated HTML) Please see added edit below as a sample.
Frameworks allow you to get the HTML of the view instead of displaying it. So if you need to generate separate tables or other elements, pass the variables to a view, and return HTML.
Different fremeworks may use various type of templating languages e.g. blade. They help formatting the data, and essentially make templates easier to work with. It's also not necessary to use them for displaying data, or if forced to use it by the framework, just do required processing before posting the variables, and just "print" it using something like {{ yourVariable }} or {{ yourVariable.someProperty }}
Edit: here's a plain PHP (not framework PHP) - simple-php-view repository as a sample view library that allows to generate HTML using variables. Could be suitable for school/university projects or such where frameworks may not be allowed.
The repository allows to generate HTML at any time by calling a function and passing required variables to it, similar to frameworks. Separately generated HTML can then be combined by another view.
It depends on the context. If you are outputting a lot of HTML with attributes, you're going to get sick of escaping the quotation marks in PHP strings. However, there is no need to use ?><p><? instead of echo "<p>"; either. It's really just a matter of personal taste.
The second method is what I usually use. And it was the default method for me too. It is just to handy to get php to work inside html rather than echo out the html code. But I had to modify the httpd.conf file as my server just commented out the php code.

How to output data after all php is executed?

I am creating breadcrumbs on my simple site.
I have some helper classes. I use them like this (just example):
$Breadcrumbs = new Breadcrumbs();
$Breadcrumbs->add(new Breadcrumb("/", "page1"));
$Breadcrumbs->add(new Breadcrumb("/", "page2"));
$Breadcrumbs->add(new Breadcrumb("/", "page3"));
$breadcrumb->show(); returns this:
<ol class="breadcrumb">
<li>page1</li>
<li>page2</li>
<li class="active">page3</li>
</ol>
So, in my project I have some switch-case constructions in which I include some files.
In this files I am using $breadcrumbs->add(...). This code:
<div class="container body">
<? $Breadcrumbs->show();?>
<?
$page = isset($_GET['page']) ? $_GET['page'] : null;
switch($page):
case "suppliers":
require_once($DOCUMENT_ROOT."/modules/suppliers.php");
break;
default:
require_once($DOCUMENT_ROOT."/modules/default.php");
break;
endswitch;
?>
<? $Breadcrumbs->show();?>
</div>
gives me this result:
Well, it works like it must work. I am using $breadcrumbs->add(...) in require files after I called $breadcrumb->show() first time thats why 1st call returns blank result. 2nd call of show() is after all breadcrumbs are added, so it returns fine result.
The questions is how to output breadcrumbs before switch blocks but with right content. Maybe I need a buffer or idk?
This is a good example of why it is such a good idea to separate out logic from presentation: you have a nice abstraction for crumb links, but can't use it properly because your other code is outputting as it goes along, rather than working with abstract data.
Obviously, you could throw away your current structure and port both logic and display directly into a new framework, but assuming you want to migrate from where you are now, here's one approach:
Create an object or array that represents the "result" of whatever module is called. Replace all current use of echo or ?> with concatenation to a string called something like $results['generic_output']. This is effectively like buffering your output, and is enough to let you use your existing abstractions like $breadcrumbs at any time. At this stage, your "template" would consist mostly of echo $results['generic_output'], plus the boilerplate header and footer which is probably already gathered in one place.
Start breaking down the output into sections. Particularly look for sections which are similar on multiple pages. For instance, if you have a "sidebar" with different content on each page but similar styling, make a $results['sidebar_content'] with just the content of that sidebar; the boilerplate to lay it out can then go into your template, and you've reduced the amount of code duplication.
Make the data you pass to the template increasingly abstract, with the goal of eventually having no HTML outside of the template(s). For instance, maybe the sidebar is made up of panels; you might start with an array of HTML blocks, one for each panel, but then turn it into an array of objects based on the actual data being displayed (say, a special offer, or the customer's current basket), with a set of templates for handling different kinds of panel. Eventually, it should be theoretically possible to build a plain-text version of your site with no HTML, just by changing the template layer, and none of the original modules.
The final step is to separate decisions about what to show from decisions about what to do. Continuing with my imaginary sidebar, your template could always receive the current basket as a general variable for use somewhere on the page, rather than as "sidebar item 1". This allows you to completely separate the actions that led into a page from the output that eventually results.
I would like to stress that this is not the way to a perfect framework, or the definitive solution to your situation, but it's one way of organising existing code (and existing thinking) in the right direction.
In the above, the "templates" could just be a set of PHP files using ?> or echo to produce the output, or it could be a dedicated templating system such as Smarty or Twig. Indeed, the point of the separation is that you could change your mind on that front later, because the result of the code modules would be an array of data to be displayed, which is just what Smarty or Twig would need as input.

Cakephp splitting long view.ctp into smaller ones

One of my view file in cake is getting very long, like 300+ lines already. And i find it very difficult to keep track of the understanding.
Is it a good idea to split them up into smaller files and then including them in the parent view file?
If its ok to be done,
In what extension should i create the smaller files? .ctp or .php?
Including them with require_once(view-child1.ext) should be fine, right?
Im fairly new to cakePHP. So i prefer advises from the experts over here. Please put me in the right direction.
EDIT
Thanks for the help guys.
I tried it. But i cant seem to pass the variable. echo $this->Element('reviews/view-goal',$history); Parent view shows and error saying undefined variable in that element.
Im calling the elements from this loop:
foreach($histories as $date => $history)
Cant pass $history. But $histories is being passed correctly.
You should make elements in View/Elements folder with .ctp extension.
This link would help you to make clean separation of your view files with the related/repeated code.
An element is basically a mini-view that can be included in other views, in layouts, and even within other elements. Elements can be used to make a view more readable, placing the rendering of repeating elements in its own file. They can also help you re-use content fragments in your application.
Elements live in the /app/View/Elements/ folder, and have the .ctp filename extension. They are output using the element method of the view:
<?php echo $this->element('helpbox'); //without extension ?>
You can pass variables from your view to the element.
In your view:
<?php echo $this->Element('reviews/view-goal', array('history' => $history));
In view-goal.ctp element you can directly access $history variable.
Yes, it is a very good idea. But don't use the normal require() of PHP.
CakePHP has a feature called "elements", a mechanism to put parts of a view into separate .ctp files. The files go in a special folder, View/Elements
You can include an element like this:
echo $this->element('sidebar/recent_comments');
If you need any variables inside the element, you need to pass them in an additional array parameter:
echo $this->element('sidebar/recent_comments', array('variable_name' => /* Variable content */));
In order to keep your view files small, you should also make sure that you put stuff that is shared by most pages (header, footer) into the Layout file. And obviously: keep JS and CSS in external files.

Best Way To Create Multi Column Page on CakePhp

I want to create a multi column page. I am not sure about which way I should prefer for adapting myself to cakephp's coding discipline.
Should I create columns on my view//index.ctp or on layouts/default.ctp
If layouts/default.ctp is the sutiable way, how can I fetch the other content? As you know, there is a line for fetching controller's view content like <?php echo $this->fetch('content'); ?> How can I fetch another content?
Simply declare a block somewhere else, in your view file for example, use start() and stop() to define a block and output it with fetch(). For example start('menu'); and then calling fetch('menu') will display the content between the start and stop call.
Read this:
http://book.cakephp.org/2.0/en/views.html#extending-views
http://book.cakephp.org/2.0/en/views.html#view-blocks
http://book.cakephp.org/2.0/en/views.html#using-view-blocks
http://book.cakephp.org/2.0/en/views.html#displaying-blocks

What is the best practice to use when using PHP and HTML?

I have been designing websites for a while now, but there is one thing that I have never been quite sure of when using PHP and HTML. Is it better to have the whole document in PHP and echo HTML like so:
<?php
doSomething();
echo "<div id=\"some_div\">Content</div>";
?>
Or have a HTML file like so and just add in the PHP:
<html>
<body>
<?php doSomething(); ?>
<div id="some_div">Content</div>
</body>
</html>
It seems tidier to echo HTML, especially if lots of PHP gets used throughout the page, but doing so loses all formatting of the HTML i.e. colors in the IDE etc.
There are varying opinions on this. I think there are two good ways:
Use a templating engine like Smarty that completely separates code and presentation.
Use your second example, but when mixing PHP into HTML, only output variables. Do all the code logic in one block before outputting anything, or a separate file. Like so:
<?php $content = doSomething();
// complex calculations
?>
<html>
<body>
<?php echo $content; ?>
<div id="some_div">Content</div>
</body>
</html>
Most full-fledged application frameworks bring their own styles of doing this; in that case, it's usually best to follow the style provided.
I think this would depend on your group's or your own decided convention. And it can and should vary depending on what type of file you're working in. If you follow the MVC pattern then your views should be the latter. If you're writing a class or some non-output script/code then you should use the former.
Try to keep a separation of display or formatting of output and the logic that provides the data. For instance let's say you need to make a quick page that runs a simple query and outputs some data. In this case (where there is no other existing infrastructure or framework) you could place the logic in an include or in the top or the bottom of the file. Example:
<?php
# define some functions here that provide data in a raw format
?>
<html>
<body>
<?php foreach($foo = data_function($some_parameter) as $key => $value): ?>
<p>
<?=$value;?>
</p>
<?php endforeach; ?>
</body>
</html>
Or you could place the logic and function definitions in an include file or at the bottom of the file.
Now if you're producing some sort of class that has output (it really shouldn't) then you would echo the HTML or return it from the method being called. Preferably return it so that it can be output whenever and however the implementer would like.
The syntax highlighting is an important benefit of the second method, as you said. But also, if you're following good practices where logic and presentation are separated, you will naturally find that your files that contain HTML are almost entirely HTML, which then, naturally, leads to your second method again. This is the standard for MVC frameworks and the like. You'll have a bunch of files that are all PHP, doing logic, and then when that's done they'll include a presentation file which is mostly HTML with a sprinkling of PHP.
Simple:
More PHP - close HTML in PHP. When you generate HTML code in PHP, when you are doing something like a class, so it is better to make it in echo.
Less PHP - close PHP in HTML. This is stuff like just putting vars into fields of HTML stuff, like forms... And such.
The best approach is to separate the HTML from the PHP using template system or at least some kind of HTML skeleton like:
<main>
<header/>
<top-nav/>
<left-col>
<body />
</left-col>
<right-col />
<footer/>
</main>
Each node represents a template file e.g. main.php, hrader.php and so on. Than you have to separate the PHP code from the templates as something like functions.php and fineally use your second approach for template files and keeping functions clean of "echos" and HTML.
If you can, use a template engine instead.
Although it is slightly easier at first to mix your HTML and PHP, separating them makes things much easier to maintain later on.
I would recommend checking out TemplateLite which is based on Smarty but is a little more light weight.
I've reached a conclusion that using views in MVC framework e.g. Laravel, Yii, CodeIgniter is the best approach even if you are not displaying the html straight away.
Inside the view do all the echoing and looping of prepared variables, don't create or call functions there, unless formatting existing data e.g. date to specific format date('Y-m-d', strtodate(123456789)). It should be used only for creating HTML, not processing it. That's what frameworks have controllers for.
If using plain PHP, create you own view function to pass 3 variables to - html file, array of variables, and if you want to get output as string or print it straight away for the browser. I don't find a need for it as using frameworks is pretty much a standard. (I might improve the answer in the future by creating the function to get view generated HTML) Please see added edit below as a sample.
Frameworks allow you to get the HTML of the view instead of displaying it. So if you need to generate separate tables or other elements, pass the variables to a view, and return HTML.
Different fremeworks may use various type of templating languages e.g. blade. They help formatting the data, and essentially make templates easier to work with. It's also not necessary to use them for displaying data, or if forced to use it by the framework, just do required processing before posting the variables, and just "print" it using something like {{ yourVariable }} or {{ yourVariable.someProperty }}
Edit: here's a plain PHP (not framework PHP) - simple-php-view repository as a sample view library that allows to generate HTML using variables. Could be suitable for school/university projects or such where frameworks may not be allowed.
The repository allows to generate HTML at any time by calling a function and passing required variables to it, similar to frameworks. Separately generated HTML can then be combined by another view.
It depends on the context. If you are outputting a lot of HTML with attributes, you're going to get sick of escaping the quotation marks in PHP strings. However, there is no need to use ?><p><? instead of echo "<p>"; either. It's really just a matter of personal taste.
The second method is what I usually use. And it was the default method for me too. It is just to handy to get php to work inside html rather than echo out the html code. But I had to modify the httpd.conf file as my server just commented out the php code.

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