SAML: add <mdui:UIInfo> element examples

[localguru]

add some mdui:UIInfo element examples for saml2_config in homeserver.yaml

[anoadragon453]

I struggled to find any documentation of this option in pysaml2's docs.

However I did find how it is processed in pysaml2's source code and it looks valid!

Just a tiny question below, otherwise lgtm.

[anoadragon453]

According to https://github.com/IdentityPython/pysaml2/blob/59d6fa5df06989525d2d7e5b8762bbfa3485ab42/src/saml2/metadata.py#L268-L276 it looks as though logo can also be a list of dicts, which looks more flexible. Any reason that's not show in the example?

[localguru]

@anoadragon453 no reasons, feel free to modify it. This is basically the config I use in my SAML config.

[localguru]

@anoadragon453 like for all elements multiple languages are possible like

ui_info:
     display_name:
       - lang: en
         text: "Display Name is the descriptive name of your service."
       - lang: de
         text: "Display Name ist der beschreibende Name Ihres Dienstes"

So I think for logo it has to look like this

           logo:
              - lang: en
                text: "https://example.com/logo_en.svg"
                width: "200"
                height: "80"
              - lang: de
                text: "https://example.com/logo_de.svg"
                width: "200"
                height: "80"

But never seen multiple logos in any config. I think we have to test that.

[localguru]

@anoadragon453 Andrew, I checked list of dicts for logo element and it is generating valid metadata /_matrix/saml2/metadata.xml:

saml2_config:

ui_info:
           [...]
           logo:
              - lang: en
                text: "https://example.com/logo_en.svg"
                width: "200"
                height: "80"
              - lang: de
                text: "https://example.com/logo_de.svg"
                width: "200"
                height: "80"

/saml2/metadata.xml:

<ns1:Logo height="86" width="200" xml:lang="de">
https://example.com/logo_de.svg
</ns1:Logo>
<ns1:Logo height="86" width="200" xml:lang="en">
https://example.com/logo_en.svg
</ns1:Logo>

The central Shibboleth IdP at my university also evaluates the language for logos. If I switch the browser between DE and EN, the corresponding logo is also displayed on the registration form of the IdP.

Furthermore I have added the keywords element.

So I mean, this is now a useful example configuration.

[anoadragon453]

Glad to hear, thank you for testing!

[clokep]

I'm unsure about documenting all the options in here, should we more clearly point to pysaml2 docs? I also don't want people to have to figure that library out though so... probably ok to add it.

See #8731 for similar thoughts.

[localguru]

@clokep I understand. The problem with the ui_info options is, that these are not documented. It took me several hours to find this out. I think these options are important, especially because of privacy_statement_url and information_url can refer to privacy statements and terms of use. This is mandatory for an SP in the German Research Network (university network in Germany) . Options such as organization and contact_person would then also have to be discussed, as these are not mandatory for the pure functionality of SAML registration.

[anoadragon453]

I'm inclined to agree with @localguru on the issue of verbosity, mainly on the importance of certain options and their lack of documentation in where we link to (perhaps a good candidate for an upstream PR from somebody as well :)

lgtm