Lightblue::Client

Arel like queries

foo = Lightblue::Entity.new(:foo)
foo.find{ field[:baz].eq(10) }.to_hash
=> {:op=>"$eq", :field=>:baz, :rvalue=>10}

query =
  entity.find do
  field[:bar]
    .eq(:foo)
    .all(field[:baz]
          .eq(field[:gorp])
          .or(field[:scrim].eq(:scram)))
end.project do
  field(:bar).match(entity.find { field[:flim].eq(:flam) })
end


query.to_hash
=>
{ entity: :foo,
  query:
    { :$all =>
      [
        { op:  :$eq, field:  :bar, rvalue:  :foo },
        { :$or =>
               [
                 { op:  :$eq, field:  :baz, rfield:  :gorp },
                 { op:  :$eq, field:  :scrim, rvalue:  :scram }
               ]
        }
      ]
  },
  projection: {
    field: :bar,
    include: true,
    match: {
      field: :flim,
      op: :$eq,
      rvalue: :flam }
  }
}

Take a look at specs/lightblue/query_spec.rb for better examples https://github.com/daviswahl/lightblue-client/blob/master/spec/lightblue/query_spec.rb

TODO:

Add nodes for the rest of the tokens outlined in the spec: http://jewzaam.gitbooks.io/lightblue-specifications/content/language_specification/search_criteria.html

Add update/create/delete

See what can be done with metadata

Entities are currently arbitrary. They could be linked to a schema, although I'm not sure if it would benefit the AST. I don't fully understand how Lightblue does field comparisons (can you compare foo_entity[:field] to bar_entity[:field] ?). Need to experiment with this and consider some kind of join syntax.