What is the right name for the manifest of an extension

Question

For my extension com_XX I created a manifest file name xx.xml and placed it in the root folder of the extension.

Somewhere, I found an extension that used the name manifest.xml. Thus I renamed mine.

During installation, no errors are reported.

Suddenly, some parts of my extensions didn't work any longer. Sind I expected other parts of code, I didn't accounted it to the name of the manifest file.

Yet, I was wrong. As I renamed it to xx.xml, suddenly errors disappeared.

So, what exactly is the right name for the main manifest file of an extenson com_XX?

Answer 1

This is documented in the Joomla docs:

https://docs.joomla.org/J4.x:Developing_an_MVC_Component/Developing_a_Basic_Component

Naming conventions (for manifest files)

The file must be named manifest.xml (only Joomla versions 2.5 and 3!) or <extension_name>.xml (Joomla versions 2.5, 3 and 4) and located in the root directory of the installation package.

Joomla 4.x: Automatic namespace mapping will fail if a manifest file named manifest.xml is used. See: https://github.com/joomla/joomla-cms/issues/37750

Therefore if the component is com_mycomponent the manifest file in Joomla4 is mycomponent.xml

Naming conventions for namespaces in the files

<!-- This is the PHP namespace under which the extension's
    code is organised. It should follow this format:
    
    Vendor\Component\ComponentName

    "Vendor" can be your company or your own name
    
    The "ComponentName" section MUST match the name used 
    everywhere else for your component. Whatever the name of 
    this XML file is, the namespace must match (ignoring CamelCase). 
-->