Updating to remove deprecation warnings when using ActiveRecord 4.

[harigopal]

Hi, because of deprecation warnings being raised by ActiveRecord (AR) 4, I've made a few changes which will probably neccessitate a major version bump. I'm sorry, but I couldn't think of any way to support the 2.x versions of ActiveRecord. :-(

Deprecations warnings removed:

count(conditions)

client.authorizations.count(:conditions => {:code => code}).zero?

...many instances of above count method were causing:

DEPRECATION WARNING: Relation#calculate with finder options is deprecated. Please build a scope and then call calculate on it instead.
DEPRECATION WARNING: The :distinct option for `Relation#count` is deprecated. Please use `Relation#distinct` instead. (eg. `relation.distinct.count`).

I replaced all instance of this count usage with:

client.authorizations.where(:code => code).count.zero?

find_or_create_by_column(value)

find_or_create_by_name(name)

caused:

DEPRECATION WARNING: This dynamic method is deprecated. Please use e.g. Post.find_or_create_by(name: 'foo') instead.

However, the suggested method works only from AR4 onwards, so I replaced it with:

where(name: name).first || create(name: name)

which works for AR3.0 onwards (where(conditions).find_or_create was only added in AR3.2)

Related changes:

I added AR4 to the Appraisals file, along with the required version of the mysql gem, and protected_attributes gem to allow mass-assignment protection in gem's model code.

RSpec results

AR2.x - Failure. AR3.x - Passes for SQLite and MySQL, and Postgres. AR4 - Passes for MySQL and Postgres. Tests don't start running for SQLite (details below).

I couldn't get AR4 specs to work with SQLite. It complains that an index name is too long:

Index name 'index_oauth2_authorizations_on_client_id_and_refresh_token_hash' on table 'oauth2_authorizations' is too long; the limit is 62 characters

Running the specs with AR4 (other DB-s) does not generate any more deprecation warnings, but the specs still have very noisy output, with AR complaining about attempts to mass-assign protected attributes (spec appears to test this). I haven't made any alterations there since its possible the specs may need to be updated (now that mass-assignment security is being moved out of the model).

I'd really appreciate it if you could take a look at the changes, and incorporate them if it makes sense. Thanks!

Note: I ran all tests with Ruby 2.0.0-p247.

[jcoglan]

Thanks for the patches!

Please fix the build on Travis, and let me know when everything works.

[harigopal]

@jcoglan I'd like you to take a look at the Travis build results. You'll notice that the failures are for ActiveRecord 2.x, and all of them are caused by the use of the where method.

I searched for a method that works with AR2.x, and isn't deprecated by AR4, but couldn't find anything.

The only fix I could think of was to check AR version manually, everywhere the where method is used (five instances in the codebase), and instead use the old count(conditions) form - which, I think, is a pretty ugly thing to do.

if defined?(ActiveRecord::VERSION && ActiveRecord::VERSION::MAJOR >= 3)
  where(:access_token_hash => hash).count.zero?
else
  count(:conditions => {:access_token_hash => hash}).zero?
end

This could also be done by capturing the NoMethodError, though that's probably more dangerous.

Thoughts?

[jcoglan]

We probably need some wrapper functions that we use like:

Helpers.count(Authorization, :access_token_hash => hash)

Those methods would use respond_to? rather than version numbers to detect capabilities and dispatch to whatever API is available.

[harigopal]

@jcoglan Is that OK?

[jcoglan]

The build looks good. Can you add an entry to .travis.yml to make it run the build with ActiveRecord 4.0 on Ruby 1.9.3 with MySQL and check that passes?

[harigopal]

There was a duplicate entry in .travis.yml for 1.9.3 MySQL AR3.2 - I replaced that with the AR4 build.

[harigopal]

@jcoglan Hey, is there something wrong with the patches / anything left to do?

[jcoglan]

I've merged it now. Thanks a lot :)