Unable to follow accounts from other ActivityPub services on the same host

[agger-magenta]

I’m on YunoHost 11.2.9.1 self-hosted on a box in my living room, domain apps.modspil.dk.

I’m running Mastodon 4.2.5~ynh1 and WriteFreely 0.14.0~ynh2.

Whenever I try to search for my WriteFreely blog handle (@agger@freely.modspil.dk) on my Mastodon instance (mastodon.modspil.dk), I get this popup error:

The reason is, as explained here, that Mastodon explicitly and deliberately prevents people from following accounts on private IP addresses.

However, a Yunohost service running on the same host will of course be seen as having a private IP if operating behind a NAT, as is very common. So as rational as this limitation might be on Mastodon in general, on Yunohost it doesn't make sense that you can't follow services running on the same Yunohost instance.

Hence, the right place to fix this might be at the level of the YNH integration of Mastodon, i.e. this repository.

Context

I’m on YunoHost 11.2.9.1 self-hosted on a box in my living room, domain apps.modspil.dk.

I’m running Mastodon 4.2.5~ynh1 and WriteFreely 0.14.0~ynh2.

• I have access to my server: Through SSH | through the webadmin
• Are you in a special context or did you perform some particular tweaking on your YunoHost instance?: no

I previously posted about this in the forum.

Steps to reproduce

Install Mastodon and WriteFreely on the same YNH instance behind a NAT.

Create a user on Mastodon and a blog on WriteFreely. Attempt to follow or find the WriteFreely blog from your Mastodon instance.

You'll find you can't and will get the 422 Mastodon::PrivateNetworkAddressError.

[agger-magenta]

A way to fix this would be to include 127.0.0.1 and the Yunohost server's internal IP in Mastodon's ALLOWED_PRIVATE_ADDRESSES setting by default. That way it would work out of the box for NAT'ed installations.