Feature: Why config of "template_dir" is just a single directory

[TomFreudenberg]

Hey @derks

in config there is the option:

### Where external templates are loaded from
template_dir: /var/lib/tokeo/templates/

but why not allowed multiple dirs or

### Where external templates are loaded from
template_dirs:
  - /var/lib/tokeo/templates/
  - /var/lib/custom/templates/
  - /xyz/templates/

If you like, I can creata a PR, currently I created my own extensions but for this I miss the reason why not by framework.

Cheers
Tom

[derks]

@TomFreudenberg this I believe was an evolution in design. I think originally we only had template_dir, and then the list of template_dirs was introduced later. Per the docs, the App.Meta.template_dir is prepended to the list of App.Meta.template_dirs and takes precedence in the loading order:

https://cement.readthedocs.io/en/3.0/api/core/foundation.html#cement.core.foundation.App.Meta.template_dir

template_dir: Optional[str] = None
        """
        A directory path where template files can be loaded from.  By default,
        this setting is also overridden by the
        ``myapp.template_dir`` config setting parsed in any of the
        application configuration files .

        If set, this item will be **prepended** to
        ``App.Meta.template_dirs`` (giving it precedence over other
        ``template_dirs``.
        """

The list of App.Meta.template_dirs is processed prior to any TemplateHandler execution to load the template.

[TomFreudenberg]

Hi @derks

I can agree but the question is if this must be the same in future.

For me, it would be great if

1. template_dir

allows to be set by external config with "single string" or (new) "list of strings"

2. template_dirs (preferred by me)

are available in external config as well

Currently neither will work.

What solution (1 or 2) would meet your needs the best?

[derks]

@TomFreudenberg I agree, I think it would make sense to add to config. This is supported though with minor modifications.
There are two settings that determine this:

• App.Meta.core_meta_override -> The list of meta options that are overridden by config options (do not modify this, used by framework)

• App.Meta.meta_override -> List of meta options defined by app developer. You can add 'template_dirs' here and it will do what you want.

• https://cement.readthedocs.io/en/3.0/api/core/foundation.html#cement.core.foundation.App.Meta.meta_override

IMPORTANT NOTE: I believe that this will only work if using the YamlConfigHandler or JsonConfigHandler, as they support more complex data types. The following example is using the YamlConfigHandler (default with cement generate project):

~/.myapp.yml:

myapp:
    template_dir: /path/to/my/template-dir
    template_dirs:
    - /path/to/template/dir1
    - /path/to/template/dir2
    - /path/to/template/dir3

main.py:

class MyApp(App)
    class Meta:
        meta_override = ['template_dirs']

You can see it is honored:

app.run()
print(app._meta.template_dirs)

Output:

['/root/.myapp/templates', '/root/.config/myapp/templates', '/path/to/my/template-dir', '/path/to/template/dir3', '/path/to/template/dir2', '/path/to/template/dir1', '/usr/lib/myapp/templates']

[derks]

@TomFreudenberg to further expand on your "ideal" request:

Setting a simple string with result in the string being expanded (as-is today). It would be a minor change to automatically convert a string to a list, but would need be implemented.

We do not have the same thing for "config_dir" vs "config_dirs", so I agree it is confusing to support both. I am in favor of deprecating "template_dir", and supporting auto conversion of a string -> list if only one is given to "template_dirs".

[TomFreudenberg]

@derks thanks for positive feedback.

Let me know if I can support you in that issue.

[derks]

Thanks @TomFreudenberg -> Does this resolve what you are seeing in Issue #745?

[TomFreudenberg]

@derks - No - but I will more precise the description on the issue #745