Rename "web" public folder to htdocs, public_html or other

Installing Drupal with Composer

After installing Drupal 9 with for example this command:

composer create-project drupal/recommended-project my_site_name_dir

Rename web folder to htdocs

We must first modify the “extra” section in the composer.json file, run the dump-autoload command and manage the configuration of the domain / vhost to point to this new folder.

After installing the files, open the composer.json and replace these lines:

"extra": {
        "drupal-scaffold": {
            "locations": {
                "web-root": "web/"
            }
        },
        "installer-paths": {
            "web/core": [
                "type:drupal-core"
            ],
            "web/libraries/{$name}": [
                "type:drupal-library"
            ],
            "web/modules/contrib/{$name}": [
                "type:drupal-module"
            ],
            "web/profiles/contrib/{$name}": [
                "type:drupal-profile"
            ],
            "web/themes/contrib/{$name}": [
                "type:drupal-theme"
            ],
            "drush/Commands/contrib/{$name}": [
                "type:drupal-drush"
            ],
            "web/modules/custom/{$name}": [
                "type:drupal-custom-module"
            ],
            "web/profiles/custom/{$name}": [
                "type:drupal-custom-profile"
            ],
            "web/themes/custom/{$name}": [
                "type:drupal-custom-theme"
            ]
        },

by (you can do a find/replace of "web" folder name and replace it with "hotdocs")

"extra": {
        "drupal-scaffold": {
            "locations": {
                "web-root": "htdocs/"
            }
        },
        "installer-paths": {
            "htdocs/core": [
                "type:drupal-core"
            ],
            "htdocs/libraries/{$name}": [
                "type:drupal-library"
            ],
            "htdocs/modules/contrib/{$name}": [
                "type:drupal-module"
            ],
            "htdocs/profiles/contrib/{$name}": [
                "type:drupal-profile"
            ],
            "htdocs/themes/contrib/{$name}": [
                "type:drupal-theme"
            ],
            "drush/Commands/contrib/{$name}": [
                "type:drupal-drush"
            ],
            "htdocs/modules/custom/{$name}": [
                "type:drupal-custom-module"
            ],
            "htdocs/profiles/custom/{$name}": [
                "type:drupal-custom-profile"
            ],
            "htdocs/themes/custom/{$name}": [
                "type:drupal-custom-theme"
            ]
        },

Regenerate autoload declarations

You need to regenerate autoload statements. To refresh autoload from composer, run the command:

composer dump-autoload

Résultat

This is what this command returns:

Generating autoload files
Generated autoload files

Conclusion

You will then need to point the domain to this new folder and your site should be up and running.