Tokens serialization

[dks17]

This is custom coder for tokens column with known object's structure (only Hash). This is based on JSON coder with some edge cases (nil, blank string).

PG registers jsonb as alias type for json and uses own text coder where also uses JSON coder and few other date/time formats for encoding/decoding.

Should help to serialize/deserialize tokens properly.

This should fix:
#1079 #121
and may:
#1240 #1224

Need help testing the PR before it will be merged.

UPDATE

• Updated dump method.
• Deleted code from load method that recognize case when json is blank string (it is unlikely case).

[MaicolBen]

@dks17 Awesome!! Can you explain what you did?

[dks17]

@MaicolBen Wrote small description about it at the top message.

[dks17]

If we care about storing null values we can delete this line.
See last_token below:

"{"nlw47IfMSJxHl8v2bvhrOw":{"token":"$2a$10$3yWVUhPtnn/vigTztah2fuioMMEB6R8aZunkFOjzguV1ZCZ8kga16","expiry":1549026407,"last_token":null,"updated_at":"2019-01-18T13:06:32.876Z"}}"

[dks17]

Serialize nil to null:

JSON.generate(nil)
=> "null"

[MaicolBen]

@dks17 Thank you for explaining this, I tested it in one app but we can check in the issue's thread if it's happening after merged

[kdubel]

Thanks for this fix! I had v1.1.0 of gem and the problem existed, updated to your fix and everything works fine. @MaicolBen maybe it's a good idea to bump version as searching for this issue takes some time?

[softwaregravy]

I'm tracing through the threads on this issue as well. I agree it would be great to get this out.