It seems, however, that the language targeting isn’t working as none of the other languages (e.g. /ja/author/ or /ja/author/james/ receive those params.
This works as expected when defined in site configuration:
[[cascade]]
foo = 'foo'
[cascade._target]
path = '/author**'
lang = '*' # You don't need to specify this; * is the default
[[cascade]]
bar = 'bar'
[cascade._target]
path = '/author**'
lang = '*' # You don't need to specify this; * is the default
kind = 'term'
[[cascade]]
baz = 'baz'
[cascade._target]
path = '/author**'
lang = '{en,es}'
Without looking at the code, in a multilingual site, if you define [[cascade]] in front matter, I would expect it to apply to the current site (language) only. Or to put it another way, I would not expect values in content/en/foo/_index.md to cascade onto content/fr/foo/something.
I think this is a documentation issue, but would appreciate confirmation/clarification from @bep.
Yes, the cascade in front matter will only cascade down on the files in that site/language. You can also define a cascade section per language in config.toml, I guess.
So would it be more idiomatic to have a series of lang specific index files with the appropriate cascade? I.e. _index.en.md, _index.ja.md, etc.? I was attempting with a single _index.md but I assume that’s only used for the site default lang?