I have a file that can either be included in a plugin, or in a theme. What's the best way to get the URL of the file's folder (from within the file)?

Edit:

I'm now using this for now

home_url( '/' . str_replace( ABSPATH, "", dirname( __FILE__ ) ) );

Let me know if there's any problem with this / there's a better way.

I have a file that can either be included in a plugin, or in a theme. What's the best way to get the URL of the file's folder (from within the file)?

Edit:

I'm now using this for now

home_url( '/' . str_replace( ABSPATH, "", dirname( __FILE__ ) ) );

Let me know if there's any problem with this / there's a better way.

• plugins
• themes

Share Improve this question edited Mar 11, 2012 at 6:52 Dogbert asked Mar 11, 2012 at 5:14 DogbertDogbert 27955 silver badges1515 bronze badges 5

• Do you know the exact location within the Plugin where the file would be located? – Chip Bennett Commented Mar 15, 2012 at 18:16
• What does this file do? There might be a better way ... And do you need the full URL or to just know the location? – EAMann Commented Mar 15, 2012 at 18:19
• @ChipBennett Nope, I don't know anything about the relative location of the file in either the plugin or the theme. – Dogbert Commented Mar 16, 2012 at 5:01
• @EAMann It's an Options page generator/helper, that could either be used by a plugin or a theme. – Dogbert Commented Mar 16, 2012 at 5:02
• 2 Since this is not quite trivial task for generic case, could you add some details how youe envision your library will be used and included in third party code? – Rarst Commented Mar 16, 2012 at 11:34

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6 Answers 6

Sorted by: Reset to default 4

See Determining Plugin and Content Directories.

plugins_url( 'filename', __FILE__ );

… returns the full URI to the file in your plugin. For themes you use:

get_stylesheet_directory_uri() . '/path/to/file';

Using ABSPATH and home_url() might not work if the wp installation is in a different directory to the url it is displayed at. You should test that out.

My thought is using the content directory as a place to do the replacement might be more robust as you can pass the resulting path into content_url() which accounts for where the WP installation is:

function get_file_url( $file = __FILE__ ) {
    $file_path = str_replace( "\\", "/", str_replace( str_replace( "/", "\\", WP_CONTENT_DIR ), "", $file ) );
    if ( $file_path )
        return content_url( $file_path );
    return false;
}

This could be simplified for unix only but the above supports windows too.

Why won't you write both case and check which one is actually pointing to a real file:

function dogbert_library_get_file_path($filename) {
    // As you might put your file in a folder, just configure this path
    $path_to_file = "files/" .$filename;

    // get_theme_root() doesn't give trailing slash
    $themeFile = get_theme_root() ."/" .get_current_theme() ."/" .$path_to_file;
    // plugin_dir_path does give trailing slash
    $pluginFile = plugin_dir_path( __FILE__ ) .$path_to_file ;

    // As we are at filesystem layer, we can use file_exists to check
    if(file_exists($themeFile)){
        return $themeFile;
    } else if(file_exists($pluginFile)) {
        return $pluginFile;
    } else {
        // Return empty as a fallback...
       return "";
    }
}

That's the best option I would see.

I suggest you use a filter.

In your file, somewhere at the very beginning, include something along the lines of:

add_filter( 'wpa45165_resource_url', 'wpa45165_resource_url_finder' );
function wpa45165_resource_url_finder( $url ) {
    $url = /* Some code to generate the url from WP_SITEURL and dirname() */;

    return $url;
}

Then, in the code that needs to reference the file, apply the filter to an empty string:

$include_url = apply_filters( 'wpa45165_resource_url', '' );

TL;DR

$themes_search_index = strpos(__FILE__,'wp-content/themes');
$plugins_search_index = strpos(__FILE__,'wp-content/plugins');
$url_postfix_prospect = dirname(__FILE__);

if( $themes_search_index !== false ){
    $url_postfix_index = strpos($url_postfix_prospect,'wp-content/themes');
} elseif( $plugins_search_index !== false ) {
    $url_postfix_index = strpos($url_postfix_prospect,'wp-content/plugins');
}

$url_prefix = get_site_url();
$url_postfix = substr($url_postfix_prospect, $url_postfix_index);
$lib_path_url = $url_prefix .'/'. $url_postfix;

echo $lib_path_url;

Given the file path...

/var/www/html/example/wp-content/plugins/my-plugin/lib/an-awesome-library/autoload.php

Results to...

http://example/wp-content/plugins/my-plugin/lib/an-awesome-library

Problem

Building a plug-and-play library for wordpress that can either be "included" inside a theme or plugin can be difficult. Wordpress has no pre-defined function for getting the URL of that file.

Solution

Treat plugins and themes separately.

Step 1. Check whether included inside theme or plugin

/**
 * Contains numeric values if the respective strings are found,
 * Contains boolean `false` if the string is not found
 */
$themes_search_index = strpos(__FILE__,'wp-content/themes');
$plugins_search_index = strpos(__FILE__,'wp-content/plugins');

Step 2a. If inside a theme

$url_postfix_prospect = dirname(__FILE__);

$url_postfix_index = strpos($url_postfix_prospect,'wp-content/themes');
$url_prefix = get_site_url();
$url_postfix = substr($url_postfix_prospect, $url_postfix_index);
$lib_path_url = $url_prefix .'/'. $url_postfix;

echo $lib_path_url;

Step 2b. If inside a plugin

$url_postfix_prospect = dirname(__FILE__);

$url_postfix_index = strpos($url_postfix_prospect,'wp-content/plugins');
$url_prefix = get_site_url();
$url_postfix = substr($url_postfix_prospect, $url_postfix_index);
$lib_path_url = $url_prefix .'/'. $url_postfix;

echo $lib_path_url;

$path = dirname(__FILE__);

should do the trick.