Mastodon instance in UBOS container: 422 Mastodon::PrivateNetworkAddressError

[jernst]

• Two Mastodon instances in a UBOS container
• Both resolve to the IPv4 address of the container's virtual gateway interface (e.g. 192.168.89.236)
• Running straight into the Mastodon server-side request forgery protection code
• However, failing to set TRUSTED_PROXY_IP to disable this.

[jernst]

See also mastodon/mastodon#31260, where they say this isn't a problem but it seems to be for me.

[jernst]

Reviewing the code shows it's a different setting: ALLOW_PRIVATE_ADDRESSES. That leads to:

• A new customizationpoint for the Mastodon package on UBOS: https://gitlab.com/ubos/ubos-app-mastodon/-/issues/13 and https://gitlab.com/ubos/ubos-app-mastodon/-/commit/faaf2c778ec5c207585916d6b54923b8a77b2911
• PR Use new UBOS allow_private_addresses customizationpoint on Mastodon and make test work #344
• Also submitted a PR for better documentation to Mastodon: Clarify the description of ALLOW_PRIVATE_ADDRESSES mastodon/documentation#1533