I'm working on figuring out how to do common things with Mustache.php.
At this point, I'm trying to replace a native php switch statement in the template.
Given a "status" flag, e.g. 'A' for Active,
and a set of display options like A => Active, I => Inactive, P=>Pending, D=>Deleted,
how would I make a nice display string in Mustache.php by modifying the data in the template?
Example data for a table:
$users = array(
array('username'=>'william', 'status'=>'A', 'date_created'=>'7-01-2012'),
array('username'=>'john', 'status'=>'P', 'date_created'=>'5-17-2012')
);
The whole point of Mustache, is having your template clean from all logic. Mustache templates should be logic-less. This is quite a different and confusing methodology for newcomers.
To solve your problem, you will need to re-process the $users array to contain everything your Mustache template will need, before-hand. e.g. if the status field switch statement was intended for displaying a human-readable status, then your View class should look something like:
class View_User {
public $_users;
public function users()
{
$users = array();
foreach ($this->_users as $user)
{
$user->status_label = // Use your 'switch' statement here
$users[] = $user;
}
return $users;
}
}
Then all your Mustache template needs to do, is output {{status_label}} like so:
<ul>
{{#users}}
<li>Status: {{status_label}}</li>
{{/users}}
</ul>
Contain your logic in View classes, and leave your Mustache templates logic-less. UI code that is separated this way makes it so much easier to maintain and re-factor later on.
Related
I'm trying to write a template in Twig. Inside it I would like it to perform some manipulations on the string data that comes from the controller. In particular, there's a common manipulation (convert from underscore_case to CamelCase) that I'd like to bring out into a separate function. Then later I can use it repeatedly like {% set x = magic(a) ~ magic(b) %}. However I cannot find how to make such a reusable function inside the template itself. There are macros, but those don't seem to be able to return values. Filters are another option that seem to fit the bill, but I can only define those on PHP side.
Can this be done? Or should I do all the advanced string manipulation controller-side? It kinda feels like I'm pulling parts of display logic in there; things that should be in the view.
Twig is for outputting data. If you need to "transform" the data you need to do that before you send it to twig or you need to extend twig
Ideally, all the data you send to twig is just variables and arrays that needs the least amount of manipulation on their own.
When you're actually "in" twig, the data processing can be assumed to be "done" and only needs to be outputted in the appropriate places with minimal logic to decide user interface styles.
So revisit your logic and prepare your data better before sending it to twig.
An example for extending a toolkit class that contains our magic methods to do real wizardry.
class CustomToolkit
{
public function magic_a($a)
{
return strtolower($a); }
public function magic_b($b)
{
return camel_case($b);
}
public function magic_tidle($a, $b)
{
return $this->magic_a($a) ~ $this->magic_b($b);
}
}
Then you add this to your twig instance. I added here a complete instantiation loop. if you have a service provider you can just grab the instance from there and add it to that one.
$twig = new Twig_Environment(new Twig_Loader_Array([
'html' => $contents
]),[
'auto_reload' => true,
'debug' => false,
]);
$twig->addExtension('toolkit', new CustomToolkit ());
echo $twig->render('html', $values);
Then in your twig code you should be able to do something along the lines of
{% set x = toolkit.magic_tidle("value","value_b") %}
You are right, macros do not have return values and you cannot really make them have any. All they do is outputting strings.
Still, you are able to capture string output using set: https://twig.symfony.com/doc/2.x/tags/set.html
The syntax looks similar to this:
{% set var %}
{{ call.macro() }}
{% endset %}
The output of the macro call is then stored inside var. You may want to strip the whitespace though.
But then, consider rethinking what you are doing. Is this still presentation logic, or is your controller simply "too lazy" to transform the strings prior to passing them to twig? If it's really presentation logic, simply adding a twig filter by extending twig surely is worth the hassle. Not only because your code becomes testable.
Can this be done?
Yes! However, Twig templates are not the ideal places to run logic. At least, we should do our best to avoid it. Instead, Controller should return what Twig template needs. Logic should run in Service, Utility, Helper (you name it) etc. and Controller returns it to Twig. Twig then just displays it.
Can twig macros return values?
Yes! Look at this example. It accepts parameters and returns (not a real "return" thing but you get the idea) something back.
Example:
Assuming that the data you are trying to manipulate is something simple.
use Doctrine\Common\Inflector\Inflector;
Controller
{
action() {
$data = Inflector::camelize('hello_world'); // This will become helloWorld
return ....;
}
}
Look into Inflector class. It has useful stuff.
This has probably been asked before, but I couldn't find the answer to my question with some preliminary searches, so here it is:
A very simple example of my current method of injecting PHP variables into HTML is as follows:
HTML (file.php):
<tag><?php echo $variable; ?></tag>
PHP:
$variable = "value";
ob_start();
include "file.php";
$results = ob_get_clean();
This achieves the correct result just fine, but it annoys me every time that I have to copy and paste those three lines to get variables injected into my HTML files. There's a chance I might want to change the details of this injection functionality at a later date, and it's currently scattered in a couple hundred locations throughout my code.
In a perfect world, I would move those three lines to a separate function that takes the file path as an input, and returns the "compiled" result. However, the function would then no longer have access to the calling scope, and I would have to pass the variables in as another input. The only thing I'm able to think of for doing that is:
function injectVariables($filePath, array $variables)
{
//Built-in PHP function, extracts array key => value pairs into variable $key = value pairs in the current scope
extract($variables);
ob_start();
include $filePath;
return ob_get_clean();
}
That certainly gets the job done, and it will be what I implement if there aren't any better solutions, but it seems less than ideal to me. It involves creating an array every time this runs, just to loop through it and extract all the variables, which just feels a bit wrong to me.
Does anyone know of any other methods that might work?
Not really sure what you are asking, but here is my answer
I don't know the structure of your code, but I hope you are using a MVC approach (or at least something which deals with classes) so that you can do the following:
In your main controller, you create a class variable like viewData which will be an array. And you put in it everything you want
$this->viewData['username'] = $username;
$this->viewData['myArray'] = array('foo' => 'bar');
$this->viewData['menuSubview'] = 'path_to_menu_subview.php';
Then, you create a render function.
public function render()
{
extract($this->viewData);
ob_start();
include("myfile.php");
return ob_get_clean();
}
And in myfile.php (with the HTML) you can simply do what you used so far
<div id="menu"><?php include($menuSubview);?></div>
<p><?=$username;?></p>
<p><?=$myArray['foo'];?></p>
The whole code can be something like this.
class Something {
protected $viewData;
protected $viewFile;
public function logic()
{
$this->userProfile();
echo $this->render();
}
public function userProfile()
{
$this->viewData['username'] = 'John The Ripper';
$this->viewFile = 'myFile.php';
}
public function render()
{
extract($this->viewData);
ob_start();
include($this->viewFile);
return ob_get_clean();
}
}
Here's a simplified class that stores data and allows for recursive rendering of files that all have access to the save data form the initial instance.
class View {
// view data
protected $_data = [];
/**
* Set view data
*/
public function __set( $key, $value )
{
$this->_data[ $key ] = $value;
}
/**
* Get view data
*/
public function __get( $key )
{
if( array_key_exists( $key, $this->_data ) )
{
return $this->_data[ $key ];
}
return null;
}
/**
* Render view file
*/
public function render( $file )
{
if( is_file( $file ) )
{
$view = $this;
ob_start();
include( $file );
return ob_get_clean();
}
return 'File not found: '.$file;
}
}
Just use the variable $view inside your included files to access the data in the class, or render() another partial file that can do the same thing, and so on.
// Bootstrap a View instance and add some data
$view = new View;
$view->dataOne = 'valueOne';
$view->dataTwo = 'valueTwo';
// Render main template
echo $view->render( 'template.php' );
Inside template.php
<header>
<?= $view->render( 'header.php' ) ?>
</header>
<h1><?= $view->dataOne ?></h1>
<p><?= $view->dataTwo ?></p>
Nothing is wrong with your injectVariables() function, it is in fact a good idea.
You shouldn't have performance impact anyway (If this is your main concern your are doing premature optimization !)
Your view (HTML) shouldn't know about the internal of your application. (You split responsability - this is a huge subject that I won't talk deep)
You know if something end-up into $variables it has been build/formatted or is revelent to be display for $filePath.
In complex system you may end up with a variable with a pdf generator, why would the HTML want that? The only purpose of the HTML is to DISPLAY HTML data.
Some variables from your logic will end-up in $variables almost every time such as session informations (Who is currently logged), for your case this is normal.
In the perfect world if you put a class into $variables it should be designed only for purpose of your HTML even if it is almost the same object as your logic.
As an exemple I designed a Session class in my logic. It does have method such as Logout() and EnsureIsAlive() as well as field such as FullName. FullName is going to be use by my HTML because I want to display it in the header of my page.
I should have a Session class for the HTML that only contains a FullName field because the HTML has only one job and is it to display data. Login() and EnsureIsAlive() are specific for the logic and aren't related at all with displaying data.
In reallity time is always a constraint and because you are writing all by yurself from scratch you may end-up just sending the logic Session class into $variables.
Design note : I'm a C# programmer and we always use class over array to pass parameters as a good pratice and it does affect the exemple about how to pass FullName to your HTML. In your case, instead of creating a class dedicated for the HTML you could also create a simple array :
$variables['Session'] = array('FullName' => $mySession->fullName).
That way you still avoid your HTML to have access to the unrelated method specific for your logic. I'm not sure if it is a good pratice in php...
Keep context variables clean
If you do call injectVariables() more than once (for different $PathFile) you may not want the same variables.
One injectionVariables() could be for a widget, another for a complete complete page.
Why would a TimeWidget need your totalInvoice variable?
You also have the ability to prepare multiples $variables at the same time because each injectVariables() will have his own parameters.
I'm not up-to-date but I know phpBB template system use (back near 2000) the exact same pattern as your injectVariables()).
You wrote that each of your page do call injectVariables(), you could also (but it may be complex) do it only in one file - like php frameworks.
Framework handle HTTP requests into one specific file
(eg. http://yoursite.com/hello/world or http://yoursite.com/login would call (internaly) http://yoursite.com/index.php?page=hello&subpage=world and http://yoursite.com?page=login).
Then this page (index.php in my exemple) would include a specific file (controller) according with his GET parameters ($_GET['page'] and $_GET['subpage']).
The controller job would be to fetch data, apply logic then fill $variables.
Then index.php will call injectVariables() with the releated HTML.
I'm using Doctrine2 and CodeIgniter2, and am new to both, as well as to OOP/MVC, so please use simple explanations :)
For testing purposes, I have a Controller a Model and a View. I want to display data from a table that contains user information. First name, last name, ID number, and so forth.
My controller makes a call to the model- which retrieves data from the doctrine entity, and then the controller passes that data to the view.
(controller)
class Test_v_to_m extends CI_Controller {
public function index() {
$this->load->model('testing/test_v_to_m_model');
$data = $this->test_v_to_m_model->display_user_info();
$this->load->view('testing/test_v_to_m_view', $data );
}
}
(model)
class Test_v_to_m_model extends CI_Model{
public function display_user_name() {
$query = $this->doctrine->em->createQuery("select u from ORM\Dynasties2\Users u");
return $query->getResult();
(view)
//print_r($data);
First question is: How do I pass the object or array along to the view in a useful way? This works if I'm just dealing with a single variable:
(controller)
$user = $this->doctrine->em->find('Entities\User', $user_id);
$data['firstname'] = $user->getFirstName();
$this->load->view('testing/test_v_to_c_view_2',$data);
(view)
echo $firstname;
But I don't know how to do something similar when its an array, or a multidimensional array.
The second question is whether or not to let the view do any real work (php logic, loops, foreach, etc) or to do all of that in the controller and have the view only do formatting and display.
Yes, You can just pass multi-dimensional array to the view and then access it as required.
e.g.
$template_date['result_arr'] = array(
array('firstname' => 'abc', 'lastname' => 'xyz')
, array('firstname' => 'abc', 'lastname' => 'xyz')
);
in your view file -
foreach($result_arr as $key => $row) {
echo $row['firstname'].' <br />';
}
Re your 2nd question - As per my understanding - it's fine to use some foreach, for loops in the view but it's best if business logic is kept to controllers and models. Hope it makes sense to you.
As for your first question, I don't know the answer off the top of my head (sorry!). I would imagine, however, that an array can be passed as part of the data (as a single item), but you would need to iterate though it in the view (see below). Just a guess, however...
As for your second question, the principle of MVC is to have only display logic in the view - so all of the "real work" should be done in the controller.
Now, if you want to have a loop to display data in a table, that's "real work" being done in the view, but since it's part of formatting and display that would be acceptable.
Regarding your first question, it's actually quite simple:
$data = array(
'firstname' => 'string',
'array' => array(1, 2, 3),
'multidimensional_array' => array('ocean' => 'deep')
);
In the view, you can access these as:
$firstname;
$array;
$multidimensional_array;
They're just exported to the view, so you can treat each key in the $data array as a variable, and the values in the $data array as the variables' values.
Regarding the second question, it is generally best if you have the view only do formatting and display. In some cases, it might be useful to use ifs or loops, for example, if you want to display different messages based on a certain variable, or if you want to fill a table with a bunch of rows. However, I strongly recommend that you keep out as much logic as possible. The view is meant to receive all the data it needs and display it in a way that suits it.
There are plenty of reasons for this, namely maintainability (if your logic changes, you don't need to update the view), reusability (if you make views as general as possible, you can reuse them very easily) and even the ability to create new views or to replace that view with a different one, without worrying about the logic.
I hope this helps. :)
I am currently working on a mashup that incorporates many data feeds. In order to display ALL of the feeds that the user wants on one page, I am currently using if statements to cross-check with the MySQL database like this:
if($var["type"]=="weather")
$var being the result of a call to mysqli_fetch_array
and then including code relevant to the function (e.g. weather) underneath, and then another "if" statement for another feed, so on so on. The problem is that there will be many feeds, and having all these "if" statements will be slow and redundant.
Is there any way to optimize this PHP code?
Another solution might be to map the "type" to a custom function using associative arrays.
e.g. (pseudo code)
function handle_wheater_logic() {
// ... your code goes here
}
function handle_news_logic() {
// .. your code goes here
}
$customFunctions = array("wheater" => "handle_wheater_logic", "news" => "handle_news_logic");
while ($row = mysql_fetch_...) {
call_user_func ($customFunctions[$row["type"]])
}
This would eliminate the need to use a lot of if statements. You might as well do the "type to function" mapping in a configuration file or maybe just store the name of the custom function to call for each "type" in a database table - that's up to you.
You can, of course also pass parameters to custom function. Just checkout the documentation for call_user_func[_array].
Try this:
$methods = array(
"weather" => function() {
// code
},
"otheroption" => function() {
}
);
Just use then $var["type"] as a index in the array to get the function:
$methods[$var["type"]]();
You can obviuosly, for better readbility do something similar:
$methods = array(
"weather" => "wheater_function",
"otheroption" => "other_function"
);
and then call the functions this way:
call_user_func($methods[$var["type"]]);
To be even more object oriented we can obviously store in the array objects implementing a particular interface, or store object redifining the __call() magic method and use it like functions.
You can use a switch statement.
A good solution for eliminating a lot of if statements and a huge switch statement just checking for one condition, would be to implement a design pattern such as the Strategy pattern.
This way you will have the code for each type separated, which makes it easier to overview and manage.
Here's an example of an implementation http://blogs.microsoft.co.il/blogs/gilf/archive/2009/11/22/applying-strategy-pattern-instead-of-using-switch-statements.aspx
Even if you won't implement this strictly it will give you some ideas on how to solve this elegantly.
Create an array that associates a function to each feed type:
$actions = array("weather" => "getWeather",
"news" => "getNews");
Then use call_user_func to call the correct one:
call_user_func($actions[$var["type"]]);
Polymorphysm for the rescue.
inteface FeedInterface {
public function retrieve($params);
}
class FeedWeather implements FeedInterface {
public function retrieve($params) {
//retrieve logic for weather feed
}
}
class FeedSports implements FeedInterface {
public function retrieve($params) {
//retrieve logic for sports feed
}
}
With use of PHP class autoloading, each of above declarations can be in a separate file, possibly namespaced as well. Then your feed retrieval code could look like this:
$class = 'Feed'.$var["type"];
$feed = new $class;
$feed->retrieve($params);
That's overly simplified and would need some additional code for error handling, discovery of non-existing classes and such, but the idea should be clear.
Using either an If Statement or a Switch statement will be faster than you care about. It might look ugly and be cumbersome to maintain but it will be fast.
I'm using this code in a views field template (in this case views-view-field--all-members--uid.tpl.php):
<?php
$users_friends = flag_friend_get_friends($user->uid);
$users_friends_ids = array();
foreach ($users_friends as $id => $value) {
$users_friends_ids[] = $id;
}
?>
It basically gets the user ids of friends and puts them in an array so I can check if the field matches any of the user ids.
So my problem is that I don't want to have this within this template (for a few reasons), but if I don't I can't access the array. How can I make this array globally accessible?
Without knowing your "few reasons", I can't say if this is the answer for sure. My own reasons would probably be that I don't want the same code executing a bunch of times, and I'd rather not have the same exact code in multiple places.
I would then create a function with a static variable to hold the friends array.
function mymodule_get_friends_ids() {
// pull in the current global user variable
global $user;
// call up the static variable
static $users_friends_ids;
// return if this static var has already been set
if (is_array($users_friends_ids)) {
return $users_friends_ids;
}
// if we hit here, then this function has not been
// run yet for this page load.
// init array
$users_friends_ids = array();
// if user is anon, no need to go on
if (user_is_anonymous()) {
return $users_friends_ids;
}
// get friends array
$users_friends = flag_friend_get_friends($user->uid);
// build ids array
foreach ($users_friends as $id => $value) {
$users_friends_ids[] = $id;
}
return $users_friends_ids;
}
Now in your templates, you can call mymodule_get_friends_ids() in as many places as you want, and the working code below the first return will only get executed the first time it is called.
Coder1's advice is very good - it keeps you from populating your global variable namespace with a lot of junk. It's probably the most "elegant." It might not be the easiest to use if you are rather new to PHP (which I'm guessing might be the case if it's hard to get your head around returning arrays, but that's ok).
However, if this is really a priority, you probably don't care about having one extra global variable.
I suppose I may be stating the obvious here - but you can, at pretty much any point in execution (provided the information you need has already been generated - e.g., the $user variable has been populated), do this:
$GLOBALS['users_friends_ids'] = /* your code goes here */
Then in your template, you access this by ...
$friendsArray = $GLOBALS['users_friends_ids'];
Or you can simply use the construct
global $user_friends_ids;
when you want to initialize the variable, or access it inside a function or class (which is the case for your template files - they are called inside functions, so you need to globalize or use the $GLOBALS array, which is "automagically" all of the variables active in the global namespace).
The most "logical" place to do this would be inside a module using one of the many hooks available, to execute this code only once. hook_init() might do it for you, if the user object is already loaded at this point (not sure, you'll have to test). But you might not want to figure out making Drupal modules (it's not that difficult).
If you are doing this inside a template (and though it's not good practice, many Drupal site owners with a beginning knowledge of PHP put everything in templates), you'll want to know which template code is being executed when. Node template code tends to be executed before page template code - which is logical, since otherwise the variables for node content in the page template wouldn't be populated.
If you have listings of nodes, they'll be calling this code multiple times, so you'll end up doing something similar to what Coder1 is describing. If you don't want to create your own small module, you could put the function declaration he's written in your theme's template.php file, since it's called only once. You don't want to put function declarations in the tpl.php files, since they are sometimes called more than once (and you aren't allowed to declare functions more than once).
If you have a hard time understanding the function and the return, you can always do something like this in your code (which is very, very inelegant - but it's better to have inelegant code that you do understand, than elegant code that's you don't).
if(!isset($GLOBALS['users_friends_ids'])) {
$GLOBALS['users_friends_ids'] = /* your code here */
}