How to use output buffering in WordPress hooked functions?

TL;DR: After the draft_to_publish hook is executed, the page is redirected, so you won’t see the echoed output.

Ref: https://wordpress.stackexchange.com/a/94011/71131

I think the problem is that the draft_to_publish action saves the post, which will call a redirect request to the browser, which loads the edit page from scratch again. Then whatever whatever scripts previously echoed at the bottom of page wouldn’t be included, as those were executed on the last page just instants before the redirect took place.

The solution should be to use a proper debug tool to output the echo’s to the javascript console. See: https://github.com/nekojira/wp-php-console

Related Posts:

  1. Add a new tab to WordPress Plugin install Listing
  2. Changing Plugin Load Order
  3. Admin settings update updating every time home page is hit?
  4. Global Objects and Public Methods
  5. How should you hook a session_start() when authoring a plugin?
  6. Init action hook running late after PayPal’s return url?
  7. How do you use the plugin boilerplate loader class to hook actions and filters?
  8. How Do I Load My Action Earlier Enough?
  9. Does WP fire delete_post when trashed posts are automatically deleted?
  10. Why does do_action pass a blank string as the first parameter if no $arg is set?
  11. How to add a link to WordPress Plugin install Listing
  12. I can’t find where a hook is being defined in a plugin – Easy Digital Downloads
  13. Call activation hook multiple times
  14. How do I handle multiple Submit buttons in plugin’s option page?
  15. Two-step login process – Is it possible?
  16. How can I hook into existing WordPress Bulk actions?
  17. Hook for post permalink update
  18. Dynamically Override Fancy Title
  19. Get returned variable from a function to add_shortcode function
  20. Earliest WP Hook to Safely and Reliably Redirect
  21. Define a function outside a class and call the function using action or filter hook
  22. Create a plugin to change the action to which a function is hooked
  23. Can I differentiate between “Delete Post Permanently” and “Empty Trash” and do something for each accordingly?
  24. Synchronize Custom post type tags to WordPress default posts tags
  25. Adding Automatically To In WordPress Using Filter Referencing?
  26. comment_email hook doesn’t seem to work for comment editor field
  27. unable to stop loop when using wp_insert_post with publish_post hook
  28. Hook into theme-switching later than `setup_theme`
  29. Add tab to profile.php wordpress plugin development
  30. Is it possible to delay execution of shortcode output callback?
  31. WordPress Ajax callback function from plugin – OOP
  32. Why my database table not created on activation?
  33. How do I change the initial quantity of a product in woocommerce?
  34. Act on user meta updated, but only once
  35. Where and how does WordPress store and use its plugin and hook information?
  36. Is there any way to allow a plugin to write over a previous version?
  37. Which are the hooks run before/after when a category’s deletion?
  38. edit_{$taxonomy} | Hook
  39. WordPress after content Hook & external template part
  40. best practice for query string values – get_query_var always empty for my value supplied in query string
  41. get_current_screen() return null
  42. Modifying meta tags after doing ajax call in plugin
  43. how to add custom functionality after woocommerce place order button
  44. Where to add hooks in a class
  45. Adding option to Gallery shortcode
  46. do_action and add_action on two different installed plugins won’t work
  47. template_redirect or admin-ajax.php?
  48. I have 2 plugins using the same wp_login action hook and one is not working
  49. Add a new confirmation page before saving
  50. How dynamic action login_form_{action} is working
  51. What happens when two or more plugins use the same hook?
  52. Does admin_print_scripts-$hook_suffix work for nested paths to individual files?
  53. Bug: Post needs to be updated twice when adding action for save_post hook
  54. flush rewrite rules after plugin update?
  55. When does save_post hook fire on post save/update
  56. Plugin does not add action
  57. Add child pages to submenu automatically
  58. After plugin activation hook
  59. How to replace default comments with custom HTML?
  60. hook filter after the_content on a specific page
  61. Is there an admin hook that will let me read GET variable before it’s too late to set the header Location
  62. Why enqueue styles on hook?
  63. Call to undefined function is_home() or any conditional tags
  64. WooCommerce change Tax Class programmatically when Recalculating an existing Order [closed]
  65. Run command “composer install” when activating wordpress plugin
  66. Add a check box in Menu Settings
  67. Hide one specific woocoomerce product
  68. Using init hook for register_taxonomy is causing invalid_taxonomy in wp_insert_term()
  69. Ajax +wordpress onClick link redirect to new page and create html content
  70. How to replace settings in WordPress plugin from a theme
  71. Redirect returning users to a certain page?
  72. Creating posts with links from a txt file
  73. Set the payment processor callbacks to a plugin
  74. Action / Hook when a new plugin is added
  75. apply_filters() and call_user_func() to define and call a function outside a class
  76. Getting Post ID at “stylesheet” and “template” hooks
  77. Trigger function on Remove block or add new block in Gutenberg JavaScript
  78. Woocommerce get_term_by() in transition_post_status hook doesn’t works
  79. Add two button to page and post admin to redirect to : add new & list of (posts – pages) just after saving post or page
  80. Limit get_next_post to posts from the same author
  81. Any way, hook to add content right before the “read more” link?
  82. Is there any way to get post meta from publish_post hook?
  83. Add a custom submenu under submenu in a Custom WordPress Plugin
  84. How do I ensure I can loop through every enqueued script and CSS?
  85. Plugin Development – Call to undefined function comment_exists()
  86. replacing jquery google cdn with a new version dynamically
  87. Prevent plugin activation and add admin notice
  88. Unable to show a message after plugin activation
  89. Does WordPress have something like timer hook?
  90. Can I use a hook other than ‘init’ to handle form submissions?
  91. Template file structure , wordpress hook for altering the template
  92. How do I replace title with my plugin?
  93. Looking for Hook that is fired after a plugin or wp upgrade is installed/updated
  94. Woocommerce: block user removing cart item
  95. how to insert content into wp_head after loop_end
  96. Apply function on all action hooks?
  97. How can I get a plugin to hook ‘dbdelta_queries’ — a filter used during version update?
  98. Send retrieve password notification email with custom HTML email template
  99. wp_head is not fired from the hook I have used in my plugin
  100. Trigger a JavaScript function based on the data fetched from Woo commerce hook