ffsync: Update syncstorage-rs to v0.21.1

[mreid-tt]

Description

This PR includes the following:

1. Update syncstorage-rs to v0.21.1

Fixes #6713

Checklist

• Build rule all-supported completed successfully
• New installation of package completed successfully
• Package upgrade completed successfully (Manually install the package again)
• Package functionality was tested
• Any needed documentation is updated/created

Type of change

• Package update

[mreid-tt]

Hey @th0ma7, thanks to your efforts to move from mysql-connector-c to mariadb-connector-c as well as your guidance for compilation on non-x64 architectures, this release is able to incorporate the latest version of syncstorage-rs and the newest compatible version of diesel. This addresses some longstanding build issues as noted in #6714 (comment) and #6228 (comment).

The package however cannot yet be merged until #6713 is resolved which is caused by an upstream incompatibility with MariaDB 10 that was introduced in syncstorage-rs v0.19.0.

[th0ma7]

I believe the fix got merged, only missing a newer release, maybe?! It may be possible for testing to checkout for that specific commit and see if it works? Using git type download. I have an example of that commented in intel-media driver or sdk if that helps, all you need is the fix commit (or using current latest on master/main or what ever branch containing the fix)

[th0ma7]

Waa worth a try ...

[mreid-tt]

Waa worth a try ...

Ok, so I got further on this working with the upstream ticket (mozilla-services/syncstorage-rs#1804). So it turns out that I can apply a slightly modified patch to achieve the same result. However the challenge I am seeing now as noted in the ticket is that it still fails to work only if I'm using unix sockets. If I turn on TCP ports on the MariaDB server and point to the localhost IP (127.0.0.1) it works just fine.

I don't know if this is something weird with the changeover to mariadb-connector-c or some other issue in our build. At this point I'm unsure of what to try next. Let me know if you have any ideas.

[mreid-tt]

Confirmed Behavior Update Based on Local Testing

I’ve completed additional testing on syncstorage-rs v0.21.1 (with the diesel-async backend) and can confirm the following:

1. Earlier versions (e.g., v0.18.3) used synchronous Diesel (v2.1.6).
   In those versions, database URLs of the form:

   mysql://user:pass@localhost/dbname
   

   worked correctly without any socket parameters. Diesel/MySQL automatically treated localhost as a Unix-socket connection, so MariaDB did not need to expose a TCP listener.

2. In v0.21.x, after the migration to diesel-async, this behavior changed:

   • localhost no longer falls back to the Unix socket.

   • The old parameter ?unix_socket=/path is not recognized (as noted in Switching to diesel-async broke use of the connection parameter ?unix_socket= mozilla-services/syncstorage-rs#1843 (comment)).

   • Without a TCP listener, syncstorage-rs fails with:

     DieselConnection(BadConnection("Input/output error: Connection refused (os error 111)"))
     

3. However, Unix-socket connections do still work—they just require the new DSN parameter:

   ?socket=/run/mysqld/mysqld10.sock
   

   Adding this to both syncstorage.database_url and tokenserver.database_url restores full functionality. Example:

   mysql://user:pass@localhost/syncstorage_rs?socket=/run/mysqld/mysqld10.sock
   

4. After adding the ?socket= parameter, the service works normally even with MariaDB TCP networking disabled.

Conclusion

This confirms a behavior change between the synchronous Diesel backend and the current diesel-async backend:
Unix sockets are still supported, but automatic socket detection via localhost no longer occurs, and the explicit ?socket= parameter is now required for socket-only installations.