https://meta.miraheze.org/wstats/custom.txt and https://meta.miraheze.org/wstats/miraheze.txt. The former is updated every puppet run and the latter 24 hours.

https://gerrit.wikimedia.org/r/#/c/328856/

example what i get when trying to talk to API of a private one:

    [code] => readapidenied
    [info] => You need read permission to use this module
    [*] => See https://wikicanada.miraheze.org/w/api.php for API usage
)

or, alternatively, you could say "all wikis should allow read permission to use statistics module" and let me get the numbers of users/admins/pages/etc. for all wikis even if the content itself is private. if that is possible i would just add all of the wikis to my stats, public or private content i would ignore.

dunno, what do you think?

There are a few different approaches possible here:

1. we try and distinguish private and public wikis (currently there's real way of doing this unless we diff the custom domains against our list of private wikis)
2. we investigate if Mediawiki has a built in way of allowing certain API modules to be "white listed" like we have a way to whitelist pages like Special:Login, CreateAccount, Main Page etc.
3. we do a old hack we did with Parsoid where we allow a single static private IP to have the "read" permission globally.
4. some bot or OAuth Magic where a single account "wikistats" can have the read permission globally.

If possible, 2 would be the best solution for all.
1 would suit you more than us and 4 would suit us more than you.
3 would also suit you but there's a risk of the IP being re-allocated, shared or so on. I imagine wikistats doesn't have its own floating public IP so this would definitely be the case of proxying and sharing correct?