I am working with a Drupal theme, and I see a lot of variables which look like were created with extract(). Is it possible to track back, and see where that array is?
I take you are referring to the variables passed to a template file, which effectively are extracted from an array.
The code that does that in Drupal 7 is in theme_render_template().
function theme_render_template($template_file, $variables) {
extract($variables, EXTR_SKIP); // Extract the variables to a local namespace
ob_start(); // Start output buffering
include DRUPAL_ROOT . '/' . $template_file; // Include the template file
return ob_get_clean(); // End buffering and return its contents
}
The function is called from theme(), which executes the following code.
// Render the output using the template file.
$template_file = $info['template'] . $extension;
if (isset($info['path'])) {
$template_file = $info['path'] . '/' . $template_file;
}
$output = $render_function($template_file, $variables);
$render_function by default is set to 'theme_render_template', but its value is set with the following code (in theme()).
// The theme engine may use a different extension and a different renderer.
global $theme_engine;
if (isset($theme_engine)) {
if ($info['type'] != 'module') {
if (function_exists($theme_engine . '_render_template')) {
$render_function = $theme_engine . '_render_template';
}
$extension_function = $theme_engine . '_extension';
if (function_exists($extension_function)) {
$extension = $extension_function();
}
}
}
Just echo the $GLOBALS variable and you might find where it came from if the array was not unset.
Im not familiar with Drupal so this is just a suggestion, but if drupal has a templating structure or if an array is passed from a controller or such then possible that extract is used,
You could use get_defined_vars within your view to get all vars and its possible that there is an array there that you can cross reference with variables you know of that are in the same array or such.
<?php
$vars = get_defined_vars();
print_r($vars);
//or maybe
print_r($this);
?>
Related
I'm currently doing a beginner course in coding, mainly focusing on PHP and in one exercise we're changing our code from including a template through normal namespacing to instead including it via a function so that we can use output buffering. To make it work we are using extract() and although I understand how extract works, I struggle to see why we need to use it to make include work. Before running it via the function, we didn't need to send in or extract new variables. Is someone able to explain the reasons behind this?
Here's what the function looks like:
const TEMPLATE_EXTENSION = '.phtml';
const TEMPLATE_FOLDER = 'templates/';
const TEMPLATE_PREFIX = 'cart_view_';
function display($template, $variables, $extension = TEMPLATE_EXTENSION) {
extract($variables);
ob_start();
include TEMPLATE_FOLDER . TEMPLATE_PREFIX . $template . $extension;
return ob_get_clean();
}
Here's how we call it:
<?php echo display('user', ['users' => $users, 'cart' => $cart]); ?>
<?php echo display('item', ['new_item' => $new_item]); ?>
<?php echo display('items', ['cart' => $cart]); ?>
And here's what's in the templates we're including:
<h2>New Item</h2>
<p><?php printf($new_item['name']);?> is $<?php printf($new_item['price']);?></p>
<h2>User: <?php printf($cart['user']); ?></h2>
<p>ID: <?php printf($users[$cart['user']]['id']); ?></p>
<p>Email: <?php printf($users[$cart['user']]['email']); ?></p>
<h2>Cart</h2>
<?php foreach ($cart['items'] as $item) {
printf("<p>%s is $%d</p>\n", $item['name'], $item['price']);
} ?>
The variables are definied in another file which is already included in the index.
Previously before using the function to buffer, all we needed was this:
<?php include 'templates/cart_view_user.phtml'; ?>
<?php include 'templates/cart_view_item.phtml'; ?>
<?php include 'templates/cart_view_items.phtml'; ?>
Functions do have their own variable scope. So when you created the display() function, it doesn't see what variables are available outside of it. See more on Variable Scopes in PHP. You are using extract() in order to convert an array into variables in the scope where you are calling it from eg: in the function.
Your first solution was probably something like this (I'm making up the variables):
$users = [];
$cart = [];
// you are including the template in the same scope as the variables are defined, aka it will "see"/have access to those variables
include 'templates/cart_view_user.phtml';
Now you have refactored your code and moved the including logic in a function. This function has its own local scope.
$users = [];
$cart = [];
function display($template, $variables, $extension = TEMPLATE_EXTENSION) {
// you don't have access to $users and $cart here as those are defined in the global scope
extract($variables); // <-- after this call you will have new variables created in the local function scope based on your $variables array
ob_start();
include TEMPLATE_FOLDER . TEMPLATE_PREFIX . $template . $extension;
return ob_get_clean();
}
So now you would have two options if you know what variables you want to make available inside the function you could use the global keyword, but I would discourage using it, it could lead to weird bugs when you don't understand why your variables being changed (ps later you will move onto using classes and you won't have the headache of global variables).
// you can drop $variables from the function signature
function display($template, $extension = TEMPLATE_EXTENSION) {
global $users, $cart, $new_item;
// no extract needed, but please try not using global, it can lead to weird bugs
ob_start();
include TEMPLATE_FOLDER . TEMPLATE_PREFIX . $template . $extension;
return ob_get_clean();
}
Or you can use the extract to create variables in the function's scope so when you include the files they will have access to those variables. On thing to note here that extract will use the array keys as the variable names it is creating. That's why you are passing in display('user', ['users' => $users, 'cart' => $cart]); after this call, extract will create a $users and a $cart variable inside the function call. If you would call it with different array keys, like: display('user', ['u' => $users, 'c' => $cart]); the included file would complain that it can't find the variables $users and $cart.
I hope this helped, feel free to ask more if I wasn't clear anywhere.
newbie in PHP here, sorry for troubling you.
I want to ask something, if I want to include a php page, can I use parameter to define the page which I'll be calling?
Let's say I have to include a title part in my template page. Every page has different title which will be represented as an image. So,
is it possible for me to call something <?php #include('title.php',<image title>); ?> inside my template.php?
so the include will return title page with specific image to represent the title.
thank you guys.
An included page will see all the variables for the current scope.
$title = 'image title';
include('title.php');
Then in your title.php file that variable is there.
echo '<h1>'.$title.'</h1>';
It's recommended to check if the variable isset() before using it. Like this.
if(isset($title))
{
echo '<h1>'.$title.'</h1>';
}
else
{
// handle an error
}
EDIT:
Alternatively, if you want to use a function call approach. It's best to make the function specific to activity being performed by the included file.
function do_title($title)
{
include('title.php'); // note: $title will be a local variable
}
Not sure if this is what you're looking for, but you can create a function to include the file and pass a variable.
function includeFile($file, $param) {
echo $param;
include_once($file);
}
includeFile('title.php', "title");
In your included file, you could do this:
<?php
return function($title) {
do_title_things($title);
do_other_things();
};
function do_title_things($title) {
// ...
}
function do_other_things() {
// ...
}
Then, you could pass the parameter as such:
$callback = include('myfile.php');
$callback('new title');
Another more commonly used pattern is to make a new scope for variables to be passed in:
function include_with_vars($file, $params) {
extract($params);
include($file);
}
include_with_vars('myfile.php', array(
'title' => 'my title'
));
The included page will already have access to those variables defined prior to the include. If you require include specific variables, I suggest defining those variables on the page to be included
i have a codeigniter application with 5 controllers one is the 'base' and the rest are inheriting form it, i am using global variable in the base to load in the view but it's not working i get (Undefined variable) when i load the view how can I fix this?
i'm using this function in the base to load the views
function _setContent($tplFile) {
ob_start();
$this->load->view($this->theme_dir . '/' . $tplFile, $this->tplData);
$_content = ob_get_contents();
ob_end_clean();
$this->tplData['_content'] = $_content;
$this->load->view($this->theme_dir . '/default', $this->tplData);
}
$this->tplData // is the global variable
you can use config class.
$this->config->set_item('global_variable', $my_var);
now you can use this variable wherever you want
$this->config->item('global_variable');
try using define() instead of global to set your variable - http://php.net/manual/en/function.define.php
I'm trying to create a small template system and have a function that loops over an array of items.
Currently I'm using the output buffering functions and include so i can load up the template file while it has scope to the class.
function loadTemplate($name, $vars) {
$buf = '';
$path = $name . '.html';
if (file_exists($path)) {
$this->vars = $vars;
ob_start();
include($path);
$buf = ob_get_clean();
}
return $buf;
}
I was just wondering if I could store the initial template in an array then have it run (As if it was included) while keeping scope, like.
function loadTemplate($name, $vars) {
$buf = $template = '';
if (isset($this->cache[$name]))
$template = $this->cache[$name];
else {
$path = $name . '.html';
$template = file_get_contents($path);
$this->cache[$name] = $template;
}
//Exec template here with scope.
}
Or am i just being pedantic and trying to micro optimize :)
If i were you and had complex operations in the template files I would save them to filesystem. I've modified your function, I think you'll understand what happens there:
<?php
function template($name, $vars = array())
{
$cache = 'cache/'; // Path to cache folder, must be writeable
$expire = 3600 * 3; // Cache lifetime, 3 hours
$path = $name . '.html';
$cache_file = $cache . sha1($path) . '.txt'; // Generate cache file path and hash-name
// If cache file exists and it hasn't expired yet we must get cached data
if (file_exists($cache_file) && filemtime($cache_file) > (time() - $expire))
{
return unserialize(file_get_contents($cache_file));
}
// Return NULL if template file doesn't exist
if (!file_exists($path))
{
return null;
}
$this->vars = $vars;
ob_start();
include_once $path;
$output = ob_get_clean();
// Save output to the cache file
file_put_contents($cache_file, serialize($output));
return $output;
}
?>
P.S. Haven't tested the function.
That's most useless cache you can implement.
You'd better think of HTTP conditional get implementation which will make no need to call temlpate at all. And then go for opcode cache which will cache your includes automatically.
But at firs you have to profile your app/templater to see if you need any cache at all
Just keep including it. The only alternative would be to read the contents then eval them, and that's going to be worse. The overhead of the second include should be significantly less since the page is already parsed into opcode...
Will be looking into CakePHP as per NullUserException's comment :)
I don't think that it makes much difference if you include an template once again, as you said yourself... it would be micro optimizing.
But, what you could do is to save the already included templates source to an array and use the template name as the key for the array.
When you run your loadTemplate function, you can just do a array_key_exists to see if it is included already.
But if I may, I would recommend the smarty template engine. I used it in my projects and find it just perfect. I have adapted it a bit to run smoother with my code, but now it really is perfect for me.
Is it possible to define private variables in a PHP script so these variables are only visible in this single PHP script and nowhere else? I want to have an include file which does something without polluting the global namespace. It must work with PHP 5.2 so PHP namespaces are not an option. And no OOP is used here so I'm not searching for private class members. I'm searching for "somewhat-global" variables which are global in the current script but nowhere else.
In C I could do it with the static keyword but is there something similar in PHP?
Here is a short example of a "common.php" script:
$dir = dirname(__FILE__);
set_include_path($dir . PATH_SEPARATOR . get_include_path());
// Do more stuff with the $dir variable
When I include this file in some script then the $dir variable is visible in all other scripts as well and I don't want that. So how can I prevent this?
There are a few things you could do to keep $dir out of subsequent files
Example 1
set_include_path(dirname(__FILE__) . PATH_SEPARATOR . get_include_path());
This is the most obvious.
Example 2
$dir = dirname(__FILE__);
set_include_path($dir . PATH_SEPARATOR . get_include_path());
// work with $dir
unset($dir);
Just unset the variable after defining it and using it. Note this will unset any variable named $dir used prior to including this script.
Example 3
define('DIR_THIS', dirname(__FILE__));
set_include_path(DIR_THIS . PATH_SEPARATOR . get_include_path());
It is less likely I suppose to redefine a global constant like this.
Example 4
function my_set_include_path {
$dir = dirname(__FILE__);
set_include_path($dir . PATH_SEPARATOR . get_include_path());
// Do more stuff with the $dir variable
$my_other_var = 'is trapped within this function';
}
my_set_include_path();
You can define as many variables within that function and not affect the global namespace.
Conclusion
The first method is the easiest way to solve this problem, however because you want to use $dir again, it may not be ideal. The last example will at least keep that $dir (and any others defined in that function) out of the global namespace.
The only way you're going to accomplish anything close to what you want is to wrap everything in that included file in a function, and call it. If the file needs to execute itself you could still do
<?php
run_myfile()
function run_myfile() {
...
}
?>
There is no generic way to make a variable scoped to only a file outside of namespaces, classes, or functions.
Well, I'm probably getting flailed for this, but you if you are totally desperate you could use a Registry for that. I've whipped up a small one that does without classes (since I assume from And no OOP is used here so I'm not searching for private class members. means you don't want to do it with OOP at all)
function ®istry_get_instance()
{
static $data = array();
return $data;
}
The static $data variable inside is persisted inside the function scope, so you can call the function wherever you like and always get the same contents. The crucial point is returning by reference, e.g.
$registry = ®istry_get_instance(); // get $data array by reference
$registry['foo'] = 'bar'; // set something to $data
unset($registry); // delete global reference to $data
print_r(®istry_get_instance()); // show $data
Obviously you'd still have $registry as a variable in the global scope when calling this method from the global scope. So, you could add some more functions to make the Registry more convenient to use, e.g. for setting data to the Registry:
function registry_set($key, $value)
{
$registry = ®istry_get_instance();
$registry[$key] = $value;
}
and for getting it out again:
function registry_get($key)
{
$registry = ®istry_get_instance();
if(array_key_exists($key, $registry)) {
return $registry[$key];
} else {
trigger_error(sprintf(
'Undefined Index: %s', htmlentities($key)
), E_USER_NOTICE);
}
}
and for checking if a key exists:
function registry_isset($key)
{
$registry = ®istry_get_instance();
return array_key_exists($key, $registry);
}
which you could then use like:
registry_set('foo', 'bar'); // setting something to the registry
var_dump( registry_isset('foo') ); // check foo is in the registry now
echo registry_get('foo'); // prints 'bar'
echo registry_get('punt'); // raises Notice
You could populate the Registry from an include file with an additional method like this:
function registry_load_file($file)
{
if(!is_readable(realpath($file))) {
return trigger_error(sprintf(
'File is not readable: %s', htmlentities($file)
), E_USER_WARNING);
}
$config = include $file;
if(!is_array($config)) {
return trigger_error(sprintf(
'Expected file %s to return an array', htmlentities($file))
, E_USER_WARNING);
}
$registry = ®istry_get_instance();
$registry += $config;
}
with the include file having to return an array:
// config.php
return array(
'setting1' => 'something'
);
and then you can do
registry_load_from_file('config.php'); // add the contents of config to registry
print_r(registry_get_instance()); // show content of registry
Of course, this is now six functions in the global scope just for not having a global variable. Don't know if it's worth it, especially since I consider static in functions and all that reference stuff doubtful practice.
Take it as a proof of concept :)
Why not just put everything in a static class? Then you only have a single "variable" that could possibly conflict with the global namespace.
class MyClass {
public static $myvar = 1;
public static $myvar2 = "xyz";
public static function myfunction() {
self::$myvar++;
self::$myvar2 = "abc";
}
}
// References to class items, if needed
MyClass::myfunction();
MyClass::$myvar += 3;
If the problem you are trying to is just:
$dir = dirname(__FILE__);
set_include_path($dir . PATH_SEPARATOR . get_include_path());
// Do more stuff with the $dir variable
Then the solution would be to change the include path relative to '.' in your ini settings. E.g. change:
include_path=includes:/usr/local/php
to
include_path=./includes:/usr/local/php
Note that a script does not come into scope except where you explicitly include/require it (both the _once check applies globally) however I would recommend strongly against calling include/require from within a function - its much more transparent having the includes/requires at the top of the script.
I think that the problem you are trying to solve is based on a false premise and you should look for another way of fixing it. If you want the code in an include file to behave differently depending on what includes it, then really you should seperate it out into 2 seperate files - or maybe even 3 - 2 for the different behaviours and 1 for the common.
C.