I am developing a shortcode for wordpress. My shortcode and widget both need to connect to an external database in order to pull in formation.
My first question is what hook do i use to connect to an external db. The way I have it set up currently it tells me the header has already been sent. I need it to send with the header to make the clean connect. I do not want to use output buffer if i don't have to. I want to make a clean connect. What hook do i use to make a connect and not get the header error?
My second question is: Is there a way for this hook to only be called on certain pages? I don't want to make this connect on every page just on the pages that contain the short code. Is there an if statement or some sort of hook filter so that the db connect is only made when needed instead of being called on every page load. Thanks.
The "wp" hook is run after the current $post is set but before the headers are output.
So you should be able to do a check like if(strpos($post->post_content, "[shortcode]") !== false) to determine if the DB connect code should run.
You would use that hook like:
add_action("wp", "my_wp"); //where "my_wp" is the name of your function
Related
I don't know the exact meaning of the question but someone asked me this question in interview. I just want to know that there's something like that, we use any route algorithm in Wordpress?
This could be a trick question because routing would mean mapping an HTTP request to trigger specific function or method that would handle the request which is not something that WordPress does (there is a section about WordPress at the bottom). In simple word, you read the HTTP request information to decide what function is going to be triggered.
Bit more details in simple words
if you are building a PHP project from scratch and want to display specific content or trigger a method/function there are usually two option (without routing)
Using POST , GET or REQUEST variables and complex conditional statements to achieve what you want, so a result URL could be something like this
http://example.com/index.php?view=pubications&per_page=5
Setting a PHP file for each type of content
http://example.com/publications.php?per_page=5
However, if you created a Router (Routing algorithm as you named it or routing system) then pushed all requests to index.php and have the latter include let's say something like this:
// Include the Router class
require('classes/router.php');
// Include functions responsible for display our content
require('view/display.php');
I'll not go into how to build a router, just giving examples assuming that you already have one just to give you an idea how routing works.
So assuming you have a router and function to display a contact form for example, you'd also include something like this:
Router::add('/contact-us', get_contact_form(),'get');
Router::add('/contact-us', handle_contact_form(),'post');
Then initialize the Router
Router::initialize('/');
Again assuming you have a complete Router, the above function would tell the index.php file to handle HTTP requests on this URL differently:
http://example.com/contact-us
If it's the default request type GET, trigger this function get_contact_form(), but if the request type is POST trigger this one handle_contact_form() which will act and display content differently depending on your needs.
That's great because it would be instead of something like
http://example.com/index.php?page=contact-us
index.php content would handle the request differently since there is no router.
// Include functions responsible for display our content
require('view/display.php');
if( isset($_GET['page']) && $_GET['page'] == 'contact-us'){
echo get_contact_form();
}
if( isset($_GET['page']) && $_GET['page'] == 'contact-us' && isset($_POST['contact_submit']) ){
echo handle_contact_form();
}
Imagine how long and ugly this would look like if you have a lot of pages and a complex site.
So back to WordPress
If you have a new installation you'd notice that the URLs looks something like this:
http://example.com/?p=62
http://example.com/?cat=1
http://example.com/?author=3
So it would just take URL parameters then build a WP_Query based on that, if is p then look for posts in database by ID, if cat then look for categories by ID and so on... (that's the simple explanation, there is a lot going on of course in the back-end, but just to give an idea).
You might notice after changing permalink structure that the above examples would now look something like this:
http://example.com/post-slug
http://example.com/author/name
http://example.com/category/uncategorized
This might look like routing, but it isn't, let's go in a bit more details about how this works.
When requesting a (pretty-link) URL on WordPress, first thing that happens is that the .htaccess looks for a folder/file with same name on the server, if it exists it will served, if not, it would send that request to the index.php file which does one thing:
/** Loads the WordPress Environment and Template */
require( dirname( __FILE__ ) . '/wp-blog-header.php' );
loading the wp-blog-header.php file, which will make a small check to make sure the code only run once then the following:
// Load the WordPress library.
require_once( dirname(__FILE__) . '/wp-load.php' );
// Set up the WordPress query.
wp();
// Load the theme template.
require_once( ABSPATH . WPINC . '/template-loader.php' );
Let's not go deeper into these files, what's concerns us the most is what 'wp-load.php' and 'template-loader.php' does
wp-load.php
This one among other things, looks for wp-config, make sure everything is set correctly, then connect to the database, of course after a lot of initialization, setting up constants loading a lot files that handles different parts of WordPress structure. Part of this process is that WordPress tries to match the request URL with a large set of rule called rewrite rules which are set of regular expressions, when a match is found WordPress will translate that URL into a database query using [WP_Query][1] class which is located at wp-includes/class-wp-query.php and this class will save the query results among other things (query type...etc)
template-loader.php
This one handles the display part, it uses some WordPress function that make use of WP_Query (eg:is_home()) to find out what type of content is to be displayed, then loads the the correct template based on that, and finally the template will use WP_Query to show the result.
I am working with the WORDPRESS REST API and Wordpress version 4.8 for an internal network page at a local office. We have permalinks disabled (security reasons) and thus I am accessing the posts object like so:
https://url/blogs/usernamehere/?rest_route=/wp/v2/posts/12345
I am able to do a GET request and can get the posts data into my view template with no issues. However, I can't seem to figure out how to consume additional content in the post object . I have followed the documentation and tried to do:
https://url/blogs/usernamehere/?rest_route=/wp/v2/posts/12345?_embed=true
But, I get a STATUS 404 .
How would I correctly apply the embed function in the URL so I can get the additional data associated with the post?
Pass the _embed global parameter without a value, per the documentation.
you should do this:
https://url/blogs/usernamehere/?_embed=true&rest_route=/wp/v2/posts/12345
Basically you add _embed=true at before other parameters and after & add other parameters.
In order to insert an article to Drupal there are thee ways of doing that:
by admin panel - really slow and not feasable if talking about 400 articles
by pure sql - number of tables that have to maintained and calculated (content, core, cat etc.) is quite high and it's not really reliable
by using drupal API - that's something that I was trying to implement but can't find a good documentation on it. What I'm trying to achieve is to use drupal classes and insert content (ie. running a PHP file with (catid,title,introtext....))
Example: what i want to add node in xyz.com/drupal site but my php code should be run in irankmedi.com
Can you please point me into direction where I can find some info on how to manage articles and categories this way?
Thanks in advance
If your request is very specific and you can't find a module that does what you need it shouldn't be too difficult to make a module on your own and import (create drupal) content from your code. Should be something like this:
Create a php file that will do the job.
At start of your script include standard Drupal's bootstrap code so you'll have all Drupal's functionality available in your script
Make code that will read content (from database or feed or something else).
Use Drupal api to insert node programatically:
https://www.drupal.org/node/1388922
Call your script manually or set cron to call it on specific time periods.
First you have to read RSS feed in drupal custom module. Then, following code can create node programatically.
$node = new stdClass();
$node->type = 'blog'; // This type should exist
node_object_prepare($node); // Sets some defaults.
$node->language = LANGUAGE_NONE; // The language of the default
$node->title = "testnode";
$node->body[LANGUAGE_NONE][0]['value'] = "Body";
node_save($node); // function that actually saves node in database
In Wordpress, how to make a API like Module, which can accept the data being passed via POST arguments. I mean, the Wordpress should be able to accept the URL calls from external, and then process it.
I mean, as the external Application or myself manually, when i call:
http://www.wordpress-site.com/test?name=james&age=14
Then how to write a module to read such incoming POST values and process it (Save them into the Database or something)
It is actually a public API.
Try with this one:
In Base page it should seems something like this :
Click Here
In Destination page it should seems something like this :
<?php if(isset($_GET['name']) && isset($_GET['age'])){
echo "name=".$_GET['name'];
echo "age=".$_GET['age'];
}
?>
Thanks.
Take a look on WordPress | Accept incoming url with variable parameters
that helps you to get the incoming parameters and wp action hook might be helpful that you want to achieve.
wp action hook
I'm putting up a site using Wordpress and I'd like to piggyback on its sessions. But I'm not finding any plugins, or even documentation. Any suggestions or references before I start hacking it?
Note: I'm asking about if and how WP uses standard PHP sessions itself, not how to add PHP sessions e.g. using session_start(). Apparently any state WP maintains is accomplished by other means. So if I want to use PHP sessions I need to add and maintain it myself entirely, using techniques like those in the thread.
Thanks all!
It's a very bad idea to modify WP Core files for the ability to use sessions. The best way I've found is to call the session_start() from init action hook.
function kana_init_session() {
session_start();
}
add_action('init', 'kana_init_session', 1);
You can place it in functions.php file of your theme.
Detailed article can be found here: http://www.kanasolution.com/2011/01/session-variable-in-wordpress/
WordPress doesn't appear to call session_start() because it wants to be stateless
and if register_globals is defined, it automatically destroys your $_SESSION
Consider using WordPress Transient API
Values stored using the Transient API are visible to all users, not just the current user, depending on the unique identifier used to retrieve the transient, you could assign each user a unique identifier essentially causing a transient to behave very much like a session.
Further considerations:
Depending on a users setup with object cache, etc., transients may
not always be stored in the DB (e.g. memcached), using transients for
sessions could mean that the data can get bulky and fill memory
quickly (in the use of memcached).
Also, it seems that WP does not do auto garbage collection for
transients:
https://wordpress.stackexchange.com/questions/6602/are-transients-garbage-collected
For what I need to do, the best answer involves:
To allow the cookie for wordpress to persist across subdomains, install the Root Cookie plugin.
sub1.domain.com has wordpress; sub2.domain.com is another site. From the other site (sub2), I read the cookies to identify who the user is and if the user is logged in.
My cookies are as follows:
[wordpress_909bb230b32f5f0473202684d863b2e0] => mshaffer|1255298821|d0249fced9c323835c5bf7e84ad3ffea
[wordpress_logged_in_909bb230b32f5f0473202684d863b2e0] => mshaffer|1255298821|56e9c19541ecb596a1fa0995da935700
Using PHP, I can loop over the cookies, parse the key=>value pairs. These cookies let me know that [mshaffer] has a cookie stored on wordpress, and also is authenticated as logged_in. The expiry of the cookie is 1255298821.
In sub2, I can query the database of wordpress and grab the user info:
SELECT * FROM `wp_users` WHERE user_login = 'mshaffer' ... grab user_id, user_email from this query
SELECT * FROM `wp_usermeta` WHERE user_id = '$user_id' ... grab lots of other data from wp
With this info, I can add to my sub2 session variable / cookie and do what I want with the data. I can identify if I am logged in, and my username ... which let's me grab lots of different data. I can now use WordPress authentication in my sub2.domain.com and redirect accordingly.
monte
{x:
Wordpress doesn't seem to use any sessions.
The best way to go about it is to use the action hooks it provides.
Have you checked the solution here this may work for here and its on easy way
http://thedigilife.com/wordpress-how-to-set-session-custom-variable-while-login/
Hooking a function with session_start() on wp_loaded seems to work in this case.
Put this code in wp-config.php at first line:
if (!session_id()) {
session_start();
}
Put this code in theme's header.php at first line:
session_start();
Then it will maintain all session variables.
If you wanna use your own session values, Wordpress does support it.
You need to add following lines at the top of wp-config.php
if (!session_id()) {
session_start();
}
Then add following line at the top of header.php
session_start();