master agent API change

[githubmanticore]

Currently changing master-agent protocol needs to update agents first only after master nodes might be updated - this needs to be fixed. It might be better to changes query request from code driven format to data driven, to send values keys(names) along with value itself.

The options are:

• BSON- use header only or one file library with BJSON implementation
• custom protocol - add blob type \ enum along with blob length and blob it self then agent will just skip unknown blobs

We need check BSON performance and overhead comparing to the current implementation to make sure that worth to implement custom protocol or BSON overhead is minor.

Another concern is to notify master that agent handles query with some unknown values and provide an option to query to fail execution in case agent does not know some query option. Some option might be important for particular queries and query should not be issues in case agent does not completely parse such query.

[githubmanticore]

➤ Ilya Kuznetsov commented:

Do you mean BSON or BJSON? It seems the specs are different http://bsonspec.org/spec.html http://bjson.org/

[githubmanticore]

➤ Ilya Kuznetsov commented:

There's even something called UBJSON http://ubjson.org/

[githubmanticore]

➤ Ilya Kuznetsov commented:

If we change the master-agent protocol, we should also unify how the queries are sent from master to agent. Because some are sent as pure API, some as sphinxql strings over api and now even as json over api.