What I Wish I'd Known When I Started

WordPress provides many convenient functions, perhaps too many. All too often, new developers reinvent the wheel, as the cliche goes, when Core already has a function or utility to accomplish the same. Five years on and thinking back to when I started building WordPress plugins, I could’ve saved a lot of time and avoided a lot of anxiety if I’d known where to look.

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1. What I Wish I’d Known
   
   When I Started
   Erick Hitter
   @ethitter
   https://ethitter.com/
   

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2. FIRST
   Can’t check if the user’s
   logged in until init
   

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3. SECOND
   The query isn’t
   
   available until wp
   

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4. THIRD
   Never build a
   
   manual link again
   

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5. Link Functions
   •get_permalink()  
   •get_page_by_path(  'about'  )  
   •get_post_type_archive_link(  'waffles'  )  
   •user_trailingslashit()  
   •get_year_link()  
   •get_adjacent_post()
   

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6. Link Functions
   •add_query_arg()  
   •remove_query_arg()
   

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7. Link Functions
   •home_url(  '/'  )

   

   

   

   Many more in

   wp-­‐includes/link-­‐template.php.
   

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8. FOURTH
   Escaping and
   
   Sanitization
   

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9. FIFTH
   Nonces
   

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10. SIXTH
    Ajax is easy
    
    with WordPress
    

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11. Ajax
    • Hook your function to one of two variable
    actions
    • Use the same action name with the request to
    admin-­‐ajax.php
    •check_ajax_referer() or use a nonce
    

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12. Ajax
    •wp_ajax_{$your_action}  
    •wp_ajax_nopriv_{$your_action}  
    • Hook to both if logged-in state isn’t relevant.
    

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13. SEVENTH
    Database Interactions
    

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14. Database Interactions
    • Use custom post types and custom taxonomies
    instead.
    • If you must, always $wpdb-­‐>prepare() your
    queries.
    

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15. Database Interactions
    •$wpdb-­‐>get_var()  
    •$wpdb-­‐>get_col()  
    •$wpdb-­‐>get_row()  
    •$wpdb-­‐>insert(  $table,  $data,  $format  )  
    •$wpdb-­‐>update(  $table,  $data,  $where,  
    $format,  $where_format  )  
    •$wpdb-­‐>query()
    

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16. EIGHTH
    Enqueue All
    
    The Things
    

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17. Register, then enqueue!
    •wp_register_style()  
    •wp_register_script()
    

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18. Enqueue!
    •wp_enqueue_style()  
    •wp_enqueue_script()
    

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19. But why?
    • Reusable
    • Dependencies
    • Versioning
    • Minification
    • Concatenation
    • CDN
    

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20. NINTH
    Cache All
    
    The Things
    

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21. Caching
    • Transients
    • Object Cache
    

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22. TENTH
    Remote Requests
    

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23. WP HTTP API
    •wp_remote_get()  
    •wp_remote_post()  
    •wp_remote_head()  
    •wp_remote_request()  
    •wp_remote_retrieve_response_code()
    

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24. ELEVENTH
    Miscellany
    

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25. Miscellany
    •get_queried_object()  
    •get_queried_object_id()  
    •wp_parse_args()
    

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26. Thanks
    Erick Hitter
    @ethitter
    https://ethitter.com/
    https://eth.pw/wcywg15
    

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