In what order add_action hooks execute?
i.e.
init
wp_head
wp_footer
after_theme_setup
etc...
???
???
???
EDIT:
I’ve also posted my solution.
“Data! Data! Data!” he cried impatiently. “I can’t make bricks without
clay.”Sherlock Holmes – The Adventure of the Copper Beeches
So let’s gather some real data from a vanilla WordPress 5.7.2 install and the TwentyTwelve theme activated with only a single Text widget.
For the home page, the following do_action / do_action_ref_array calls are made in the following order (logged out):
[0] => mu_plugin_loaded
[1] => muplugins_loaded
[2] => registered_taxonomy
[3] => registered_taxonomy
[4] => registered_taxonomy
[5] => registered_taxonomy
[6] => registered_taxonomy
[7] => registered_post_type
[8] => registered_post_type
[9] => registered_post_type
[10] => registered_post_type
[11] => registered_post_type
[12] => registered_post_type
[13] => registered_post_type
[14] => registered_post_type
[15] => registered_post_type
[16] => registered_post_type
[17] => plugins_loaded
[18] => sanitize_comment_cookies
[19] => wp_roles_init
[20] => setup_theme
[21] => unload_textdomain
[22] => load_textdomain
[23] => after_setup_theme
[24] => load_textdomain
[25] => load_textdomain
[26] => auth_cookie_malformed
[27] => set_current_user
[28] => init
[29] => registered_post_type
[30] => registered_post_type
[31] => registered_post_type
[32] => registered_post_type
[33] => registered_post_type
[34] => registered_post_type
[35] => registered_post_type
[36] => registered_post_type
[37] => registered_post_type
[38] => registered_post_type
[39] => registered_taxonomy
[40] => registered_taxonomy
[41] => registered_taxonomy
[42] => registered_taxonomy
[43] => registered_taxonomy
[44] => widgets_init
[45] => register_sidebar
[46] => register_sidebar
[47] => register_sidebar
[48] => wp_register_sidebar_widget
[49] => wp_register_sidebar_widget
[50] => wp_register_sidebar_widget
[51] => wp_register_sidebar_widget
[52] => wp_register_sidebar_widget
[53] => wp_register_sidebar_widget
[54] => wp_register_sidebar_widget
[55] => wp_register_sidebar_widget
[56] => wp_register_sidebar_widget
[57] => wp_register_sidebar_widget
[58] => wp_register_sidebar_widget
[59] => wp_register_sidebar_widget
[60] => wp_register_sidebar_widget
[61] => wp_register_sidebar_widget
[62] => wp_register_sidebar_widget
[63] => wp_register_sidebar_widget
[64] => wp_default_scripts
[65] => wp_register_sidebar_widget
[66] => wp_register_sidebar_widget
[67] => wp_register_sidebar_widget
[68] => wp_register_sidebar_widget
[69] => wp_register_sidebar_widget
[70] => wp_register_sidebar_widget
[71] => wp_register_sidebar_widget
[72] => wp_register_sidebar_widget
[73] => wp_register_sidebar_widget
[74] => wp_register_sidebar_widget
[75] => wp_register_sidebar_widget
[76] => wp_register_sidebar_widget
[77] => wp_register_sidebar_widget
[78] => wp_register_sidebar_widget
[79] => wp_register_sidebar_widget
[80] => wp_register_sidebar_widget
[81] => wp_register_sidebar_widget
[82] => wp_register_sidebar_widget
[83] => wp_register_sidebar_widget
[84] => wp_register_sidebar_widget
[85] => wp_register_sidebar_widget
[86] => wp_register_sidebar_widget
[87] => wp_register_sidebar_widget
[88] => wp_register_sidebar_widget
[89] => wp_register_sidebar_widget
[90] => wp_register_sidebar_widget
[91] => wp_register_sidebar_widget
[92] => wp_register_sidebar_widget
[93] => wp_register_sidebar_widget
[94] => wp_sitemaps_init
[95] => wp_loaded
[96] => parse_request
[97] => send_headers
[98] => parse_tax_query
[99] => parse_query
[100] => pre_get_posts
[101] => posts_selection
[102] => wp
[103] => template_redirect
[104] => get_header
[105] => wp_head
[106] => wp_enqueue_scripts
[107] => wp_default_styles
[108] => enqueue_block_assets
[109] => wp_print_styles
[110] => wp_print_scripts
[111] => wp_body_open
[112] => parse_tax_query
[113] => parse_query
[114] => pre_get_posts
[115] => parse_tax_query
[116] => posts_selection
[117] => parse_tax_query
[118] => parse_query
[119] => pre_get_posts
[120] => parse_tax_query
[121] => posts_selection
[122] => parse_tax_query
[123] => parse_query
[124] => pre_get_posts
[125] => parse_tax_query
[126] => posts_selection
[127] => parse_tax_query
[128] => parse_query
[129] => pre_get_posts
[130] => parse_tax_query
[131] => posts_selection
[132] => parse_term_query
[133] => pre_get_terms
[134] => loop_start
[135] => the_post
[136] => get_template_part_content
[137] => get_template_part
[138] => parse_comment_query
[139] => pre_get_comments
[140] => parse_comment_query
[141] => pre_get_comments
[142] => comment_form_comments_closed
[143] => loop_end
[144] => get_sidebar
[145] => dynamic_sidebar_before
[146] => dynamic_sidebar
[147] => dynamic_sidebar_after
[148] => get_footer
[149] => twentytwelve_credits
[150] => wp_footer
[151] => wp_print_footer_scripts
[152] => shutdown
using the must-use plugin:
add_action( 'all', function ( $tag ) {
static $hooks = array();
// Only do_action / do_action_ref_array hooks.
if ( did_action( $tag ) ) {
$hooks[] = $tag;
}
if ( 'shutdown' === $tag ) {
print_r( $hooks );
}
} );
that prints the collected action hooks, for the current page, in the last available core action (shutdown).
If you want to check the order of actions and how many times each one is fired, then you can use for example:
add_action ( 'shutdown', function(){
print_r ( $GLOBALS['wp_actions'] );
} );
or without explicit globals:
add_action ( 'shutdown', function() use ( &$wp_actions ) {
print_r ( $wp_actions );
} );
that outputs the array:
[mu_plugin_loaded] => 1
[muplugins_loaded] => 1
[registered_taxonomy] => 10
[registered_post_type] => 20
[plugins_loaded] => 1
[sanitize_comment_cookies] => 1
[wp_roles_init] => 1
[setup_theme] => 1
[unload_textdomain] => 1
[load_textdomain] => 3
[after_setup_theme] => 1
[auth_cookie_malformed] => 1
[set_current_user] => 1
[init] => 1
[widgets_init] => 1
[register_sidebar] => 3
[wp_register_sidebar_widget] => 45
[wp_default_scripts] => 1
[wp_sitemaps_init] => 1
[wp_loaded] => 1
[parse_request] => 1
[send_headers] => 1
[parse_tax_query] => 9
[parse_query] => 5
[pre_get_posts] => 5
[posts_selection] => 5
[wp] => 1
[template_redirect] => 1
[get_header] => 1
[wp_head] => 1
[wp_enqueue_scripts] => 1
[wp_default_styles] => 1
[enqueue_block_assets] => 1
[wp_print_styles] => 1
[wp_print_scripts] => 1
[wp_body_open] => 1
[parse_term_query] => 1
[pre_get_terms] => 1
[loop_start] => 1
[the_post] => 1
[get_template_part_content] => 1
[get_template_part] => 1
[parse_comment_query] => 2
[pre_get_comments] => 2
[comment_form_comments_closed] => 1
[loop_end] => 1
[get_sidebar] => 1
[dynamic_sidebar_before] => 1
[dynamic_sidebar] => 1
[dynamic_sidebar_after] => 1
[get_footer] => 1
[twentytwelve_credits] => 1
[wp_footer] => 1
[wp_print_footer_scripts] => 1
[shutdown] => 1
where we can get the total count with echo array_sum( $GLOBALS['wp_actions'] );
Here’s a prettified version:
add_action ( 'shutdown', function() {
foreach ( $GLOBALS['wp_actions'] as $action => $count ) {
printf( '%s (%d) <br/>' . PHP_EOL, $action, $count );
}
} );
or without explicit globals:
add_action ( 'shutdown', function() use ( &$wp_actions ) {
foreach ( $wp_actions as $action => $count ) {
printf( '%s (%d) <br/>' . PHP_EOL, $action, $count );
}
} );
to get the following list:
mu_plugin_loaded (1)
muplugins_loaded (1)
registered_taxonomy (10)
registered_post_type (20)
plugins_loaded (1)
sanitize_comment_cookies (1)
wp_roles_init (1)
setup_theme (1)
unload_textdomain (1)
load_textdomain (3)
after_setup_theme (1)
auth_cookie_malformed (1)
set_current_user (1)
init (1)
widgets_init (1)
register_sidebar (3)
wp_register_sidebar_widget (45)
wp_default_scripts (1)
wp_sitemaps_init (1)
wp_loaded (1)
update_option (1)
update_option__transient_doing_cron (1)
updated_option (1)
set_transient_doing_cron (1)
setted_transient (1)
requests-requests.before_request (1)
requests-curl.before_request (1)
http_api_curl (1)
requests-curl.before_send (1)
requests-curl.after_send (1)
requests-curl.after_request (1)
requests-requests.before_parse (1)
http_api_debug (1)
parse_request (1)
send_headers (1)
parse_tax_query (9)
parse_query (5)
pre_get_posts (5)
posts_selection (5)
wp (1)
template_redirect (1)
get_header (1)
wp_head (1)
wp_enqueue_scripts (1)
wp_default_styles (1)
enqueue_block_assets (1)
wp_print_styles (1)
wp_print_scripts (1)
wp_body_open (1)
parse_term_query (1)
pre_get_terms (1)
loop_start (1)
the_post (1)
get_template_part_content (1)
get_template_part (1)
parse_comment_query (2)
pre_get_comments (2)
comment_form_comments_closed (1)
loop_end (1)
get_sidebar (1)
dynamic_sidebar_before (1)
dynamic_sidebar (1)
dynamic_sidebar_after (1)
get_footer (1)
twentytwelve_credits (1)
wp_footer (1)
wp_print_footer_scripts (1)
shutdown (1)
PS: You should also check out the great Query Monitor plugin by John Blackbourn. (I’m not related to this plugin)
