all older than 2.3 are already EOL and 2.4 will be EOL soon and the next
diaspora major version will already depend on newer versions, so we can
already remove it now.
Using the real entities for the tests also uncovered some bugs where for
example empty strings are converted to nil and the validation wasn't
invalid in this case, but should be.
This is much easier and safer than "guessing" the class name based on
the validator name. That can cause a problem when another class with the
same name is found. The "guessing" was only added because we used
OpenStruct in the tests, but we shouldn't change the code only to make
tests run. I changed the tests to use the real entities, with
auto-validation disabled in the constructor, so we can test the
validator manually.
Sometimes messages contain characters that are invalid for XML, but they
are filteres out before creating the XML, otherwise the property would
be empty in the XML.
But for relayables the value is also used for creating the signatures,
so we need to filter the invalid characters earlier, before calculating
the signature.
This is needed so we can make sure to not overwrite newer data by older
one, for example when there are two edits close together and the newer
arrives faster.
The limit was added in 2012 to prevent spam, but since the participants
need to be a mutual contact with the author nowadays, I don't think it's
a spam problem anymore.
I also added a validation for the minimum count of the participants,
because a conversion without participants doesn't make much sense.
This module can be used to compute account migration signature in other
objects besides Entities::AccountMigration. For instance this is to be
used in AccountMigration model of diaspora* web application.
This was a problem with dislikes.
It's safe to use `to_s` here, because we have only strings, numbers and
booleans here anyway, because relayables don't support nested entities.
`to_s` is used to generate the `signature_data` string too.
