Limit number of custom posts per taxonomy

In this specific case it is better to have some handling of bad configuration than trying to prevent it from happening, as there are just too many possible ways in which it can happen without coming from the post edit page. Short list that comes to my mind right now

  • quick edit from the post list
  • bulk update from the post list
  • any plugin that may combine terms
  • remote publishing via xml-rpc or the rest api

Blocking the save, especially for users that do not use the post edit screen, is going to end in bad UX as the user will not know why the save fails.

Related Posts:

  1. get_query_var() not working in pre_get_posts
  2. Creating a function that receives the taxonomy terms that have been changed in a custom post type
  3. In child theme, add CPT to custom taxonomy registered in parent theme
  4. Store a value in global scope after init hook is fired
  5. Changing CPT permalink
  6. How to Add Custom Taxonomy To Woocommerce Plugin
  7. Exclude a category from WP_Query
  8. Check if post type has term
  9. Custom taxonomy not showing up when adding a new custom post type
  10. query multiple taxonomies
  11. wp_set_object_terms() is not replacing term, but creating a new one
  12. WordPress custom taxonomy URL rewrite on spelling errors
  13. Custom Post Type Permalink For Parent/Child, 404 Page Not Found Error
  14. Create an archive page for custom taxonomies
  15. Rewrite permalinks for custom posttype and custom taxonomy
  16. How to check if last uri segment is a custom post type or taxonomy term?
  17. Categories under custom post types doesn’t show properly
  18. Sort the main query in subcategories/terms?
  19. Highlight nav menu terms
  20. Custom Post Types, Custom Taxonomies and Permalinks ?
  21. get a list of posts from Custom Taxonomy
  22. Trying to manage templates on a blog with lots of custom taxonomies
  23. How to register custom post types in a plugin?
  24. Display Custom Category (taxonomy) Name in Custom Post Type
  25. Separate Posts and Custom Post Type in Custom Taxonomy archive template
  26. removing custom tax & CPT slug, adding taxonomy term in front of custom type
  27. Order WordPress Custom Taxonomy Pages & Pagination Not Working
  28. Custom post type and taxonomy permalinks – Structure
  29. Best action hook to create custom post and assign taxonomy terms to it on plugin activation?
  30. Custom Post Types relationships
  31. How many Custom Post Types to register?
  32. How can i skip same post from taxonomy term?
  33. Set menu active state for custom posttype and category, given custom taxonomy term
  34. How to bulk copy custom fields between custom posts?
  35. get_attached_media() on author page not working
  36. Posts are duplicating on wp_post_update
  37. Custom post type structure for posts with multiple child posts
  38. Search / Filter posts on Title/Content OR Tags
  39. How to display custom taxonomies with links in filter menu?
  40. List custom taxonomy specific to one custom post type
  41. Hide parent categories when clicked, and show it’s childs
  42. Get unique superset of taxonomy terms from a list of custom posts in another hierarchical taxonomy
  43. I want to change the word “Tags” in WordPress to something else, but how?
  44. How to have this permalink structure: post_type/postname/custom_inner_page
  45. Set post terms for multiple posts
  46. Display Registered Taxonomies
  47. Pagination Not Working for Custom Taxonomy with Custom Query – 404 Error
  48. Custom Taxonomy Is Being Pulled into a Page, But It Doesn’t Have A Hyperlink
  49. Querying two taxonomies with tax_query not woking
  50. Display custom posts randomly in custom taxonomy archive
  51. WP_Query parameter conflict
  52. providing access to post_id or post inside functions.php
  53. How to get all posts related to particular category name on button click?
  54. Urls in Custom Post Type work for Terms but not for its Taxonomies
  55. List all Custom Post Type posts excluding certain Taxnomy term
  56. Display custom posts for each category from its custom taxonomy
  57. Get custom category ID of current custom post within the loop
  58. Can’t pull posts of a Custom Post Type based on the custom taxonomy of the CPT
  59. Conditional Statements
  60. Add filter to Admin list for all custom post types by their custom taxonomies
  61. Single.php for Custom Post Type > Taxonomy > Term
  62. Get newest created custom category (get_term_by and variables) (outside Loop)
  63. Custom Taxonomy Taxonomies of Same Name point to first created URL
  64. Displaying custom taxonomy menu in custom post type archive
  65. Custom post types templates
  66. prevent sub categories to show up
  67. Taxonomy terms with the same name are updated between separate custom post types
  68. Custom taxonomy permalink without term, redirection to CPT slug
  69. Custom post type category link redirecting to 404 page
  70. Using `set_transient()` when saving a custom post type
  71. Archive page URL for custom taxonomy and post type
  72. Display post count for a specific month
  73. Add html tot CPT edit screen – no metabox
  74. Custom Post Type Archive Page showing as 404
  75. Custom taxonomy terms hierarchical navigation
  76. Create custom post type categories
  77. Multiple Custom Post Type in Taxonomy Archive Causing White Screen
  78. Adding a Section for Visitors
  79. Add other all taxonomies as meta boxes to custom post type
  80. How to get post type archive category title
  81. Remove CPT Slug with 2 taxonomies and 1 post meta
  82. URL with Hierarchical Taxonomies and same slug for all terms and sub-terms
  83. Should I make a taxonomy to organize data like this?
  84. Display Custom taxonomy, Child terms and posts in a template Under Specific Parent terms
  85. Associate custom categories to different user IDs
  86. List all posts from custom post type by taxonomy
  87. archive-{custom_post_type}.php not getting recognized wordpress
  88. How to retrieve the permalink for a specific (custom) term?
  89. Values inside a custom field to determine which category posts to display
  90. changing post type in loop query
  91. Taxonomy and Rewrite Structure
  92. Pagination for a Custom Taxonomy
  93. Trying to create hierarchy between 3-4 custom post types
  94. Custom Post Type Base URL
  95. Only One Post of Custom Post Type Appearing on Template Page
  96. Code to show related posts (custom post type and custom taxonomy/category) is messing with other code
  97. register_term_meta not working
  98. Custom Post Type urls not working
  99. pre_get_posts causes Custom Posts appear under ‘Pages’ menu
  100. Show a wordpress custom post condtionally using a category term