Run code before WordPress loads and insert data into WP if need be

Unless performance is a huge factor, or you need to change PHP session globals, you don’t need to run anything before wordpress, just write a plugin that makes the checks needed on the init hook and die() if needed. This way you can also store the data wherever it is convenient for you.

For sure editing any wordpess core file is a big no-no which amount to forking wordpress with all the responsibilities it requires from you. The only file you may edit is wp-config.php but this should probably be done only if the plugin approach will not work

Related Posts:

  1. error_log() output for print_r() appearing on page
  2. Allow only 1 taxonomy per custom post type [duplicate]
  3. Custom plugin: Trying to show saved data on frontend
  4. Do I require the use of nonce?
  5. Fatal error: Call to undefined function plugin_dir_path()
  6. How to make WordPress plugin check for database changes and then do something?
  7. How to change date language without changing the entire site language?
  8. Save selected item from dropdown menu in a meta box as a metadata value for a custom post type
  9. How to use copy() function and paste file in /wp-content/themes directory
  10. OOP Plugin Development. Including external object
  11. Authenticating to WordPress, using my own authentication two-factor system
  12. Use composer to load custom classes [closed]
  13. wordpress custom endpoint multiple params
  14. Create table in database when activating plugin
  15. Problem with WordPress Ajax form
  16. allow user to select pages from dropdown in my plugin
  17. Am I not understanding plugins?
  18. Using Font Awesome as post thumbnail
  19. How to set a custom path, for ajax image upload folder in admin?
  20. admin-ajax.php responding with 0
  21. Page Reloads Before AJAX Request Finishes
  22. Add htaccess rules with insert_with_markers at beginning of htaccess
  23. Insert array data on plugin activation
  24. WordPress php filter admin_body_class not working
  25. Adding Default Settings to Theme My Login plugin
  26. Append HTML Using Shortcode
  27. Create onClick Event to Re-load a Widget
  28. Accessing the database from a plugin outside of action hooks
  29. Adding subdomain to home_url for “add_menu_page”
  30. How to select the contents in the text view textrea in wp_editor?
  31. Hide categories that are not used in the post type
  32. Automated Cart Update With Alert Box Each Time
  33. WooCommerce/WordPress: how hide entire table form after submit (Admin Dashboard)?
  34. How to sanitize any integer input field in wordpress?
  35. WordPress ajax doesn’t display object method on jQuery .change() function
  36. filter default query to show just selected level of child pages in wordpress
  37. How to make my custom widget appear within WordPress widgets? Plugin development
  38. How to auto fetch customer details in Woocommerce in checkout page
  39. Can’t upload image using media_sideload_image
  40. Adding widgets to my plugin page instead of WordPress dashboard
  41. How to insert data into database using wp cron job
  42. Access Child Class of Plugin Main Class Instance
  43. Font Awesome changing default WordPress Font
  44. Download full html page with CSV export plugin
  45. How to hook code to show after the_content?
  46. Problem with AJAX in wordpress plugin
  47. Usage of call back function of add_meta_box()
  48. how to save checkbox data for custom setting?
  49. How to Schedule Cronjobs for start of every month and year
  50. WordPress WP_Query without query GET parameters
  51. Where to copy woocommerce files to in my custom theme to avoid editing the core plugin?
  52. How to override a plugins script
  53. Woocommerce custom Plugin in wordpress [closed]
  54. Removed jQuery script from header.php , any problems?
  55. How can I get plugin meta data without knowing the plugin folder?
  56. calling admin-ajax.php from admin-ajax.php
  57. Flatten Responses returned via WP REST API via WP_Error for obfuscation
  58. How does add_option() function enable action hooks to fire right after actiavtion?
  59. Create plugin with custom page and template caused an error `Call to undefined function get_header()`
  60. Settings API form – submit with AJAX
  61. Post form – AJAX won’t upload featured image – Plugin development
  62. WP Hook Before a post is created
  63. Submit remote form to wordpress REST API and save data to custom post type
  64. Foreach Loop Of Post Types With Nested If Else If Not Completing Process
  65. In a foreach loop, how can I add a meta value if it doesn’t exist?
  66. Looping through and combining calls to Woocommerce REST API
  67. Should I use wp_cache in my plugin to make it faster?
  68. Store user form submitted information in post type
  69. How to import woocommerce custom fields data into another site?
  70. Add a custom link to each image in WordPress gallery
  71. Problem with my Login Plugin
  72. How to access this jQuery/AJAX data in a PHP file/WordPress plugin
  73. How to return html as a string from php for WordPress
  74. post_exists stops working in a scheduled event
  75. register dependency css and js inside a plugin class
  76. When I create a new custom post type, it replaces the old post type
  77. Taxonomy Child Term, Counter is staying on 0
  78. Help on Wp_query to print an term
  79. Add .php to end of all WordPress Pages (multisite)
  80. Upload images from one server to an other in wordpress
  81. PHP get_category() function redeclared
  82. Getting Member Data From WhishList Member on Register
  83. Setting at job with shortcode not working
  84. Singleton plugin activation; create database
  85. PHP: Why does my code work in index.php but not a widget?
  86. How to use Amazon Elastic Transcoder from WordPress using AWS SDK for PHP?
  87. Accessing Variables Used In a Plugin Using PHPStorm + XDebug
  88. How to get WordPress Adminmenu items?
  89. How keep woocommerce users separeted in multisite install and keep admins on network
  90. I’m not able to get access $wpdb in my php file in wordpress
  91. How do I change the Go To Categories link in the term_updated_messages
  92. Import js variables loaded via wp_localize_script() into js module without global scope connection
  93. Custom taxonomy with page post type – WordPress
  94. Query posts by custom taxonomy slug in WP REST API?
  95. oneOf JSON Schema validation not properly working for custom post meta value?
  96. Too few arguments at registering new templates in my plugin
  97. I want to lists posts in wordpress to nearest location entered by the user
  98. Displaying custom meta box value in a custom post page
  99. how to check elementor is widget is active or loaded
  100. Create a custom plugin with dynamic child pages listing database records