[IMPROVE] General federation improvements

[MarcosSpessatto]

Proposed changes (including videos or screenshots)

I know this changed a lot of files, but the main goal for this PR is not to change any behavior, the goals for the PR are:

• Refactor the code;
• Solve any tech debt;
• Simplify and reuse some parts of the code;
• Remove duplicated code;
• Remove all unsafe type castings;
• Solve all Eslint errors and warnings;
• Split too big files;
• Encapsulate the business logic in a better way, avoiding exposing and leaking internal logic to the unintended layers;
• Improve the actual test cases;
• Add more test cases, since a lot of cases were omitted during the release phase;
• Remove unsafe Object.assign statements and prefer to use the class constructor instead;

Issue(s)

Steps to test or reproduce

Further comments

[CLAassistant]

All committers have signed the CLA.

[kodiakhq]

This PR currently has a merge conflict. Please resolve this and then re-add the ['stat: ready to merge', 'automerge'] label.

[MarcosSpessatto]

I don't have the knowledge to say it will in fact break both systems, but the isRemote flag is also a generic flag to identify "not local users".. introducing a new flag can cause other issues as well, like we need to make sure to filter both out..

there is at least another place missing an update to consider the new flag, the statistics for federated users:
Rocket.Chat/apps/meteor/app/statistics/server/lib/statistics.ts

Line 275 in 8c2c016

statistics.federatedUsers = federationOverviewData.numberOfFederatedUsers;
I wonder if there are others as well

I understand your point and I agree with the statistics example you gave. Indeed both flags are being used for the same purpose, but I respectfully disagree we should use the same for either "old federation" and the new version of it, since if we are using both at the same time, changes happening in one feature will affect directly the other. Another example will be, if you are using the old federation and you enable the new one, some unpredictable things could happen since you will start to use data from one federation to another. Maybe @alansikora can help us on this as well.

[alansikora]

It is exactly what @MarcosSpessatto said. We can't.

And the old federation is going to be removed anyway, so we should not bother about it. We will ensure a full cleanup when the time to remove the old federation comes.

Just so that PR can be merged and Diego is on PTO. Sorry Diego