Class: GraphQL::RemoteLoader::Loader

Inherits:
Batch::Loader
  • Object
show all
Defined in:
lib/graphql/remote_loader/loader.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.load(query, context: {}) ⇒ Object

Delegates to GraphQL::Batch::Loader#load We include a unique prime as part of the batch key to use as part of the alias on all fields. This is used to a) Avoid name collisions in the generated query b) Determine which fields in the result JSON should be

handed fulfilled to each promise



14
15
16
17
18
19
20
21
22
23
 
# File 'lib/graphql/remote_loader/loader.rb', line 14

def self.load(query, context: {})
  @index ||= 1
  @index += 1

  prime = Prime.take(@index - 1).last

  store_context(context)

  self.for.load([query, prime, @context])
end

.load_on_relay_node(node_id, type, selections, context: {}) ⇒ Object

Shorthand helper method for #load calls selecting fields off of a ‘Node` type E.g. `load_on_relay_node(“nodeid”, “Type”, “friends(first: 5) { totalCount }”)` is identical to load(“node(id: ”nodeid“) { … on Type { friends(first: 5) { totalCount } } }”)



41
42
43
44
45
46
47
48
49
50
51
 
# File 'lib/graphql/remote_loader/loader.rb', line 41

def self.load_on_relay_node(node_id, type, selections, context: {})
  query = <<-GRAPHQL
    node(id: \"#{node_id}\") {
      ... on #{type} {
        #{selections}
      }
    }
  GRAPHQL

  load(query, context: context)
end

.load_value(*path, context: {}) ⇒ Object

Loads the value, then if the query was successful, fulfills promise with the leaf value instead of the full results hash.

If errors are present, returns nil.



29
30
31
32
33
34
35
 
# File 'lib/graphql/remote_loader/loader.rb', line 29

def self.load_value(*path, context: {})
  load(query_from_path(path), context: context).then do |results|
    next nil if results["errors"] && !results["errors"].empty?

    value_from_hash(results["data"])
  end
end

.reset_index ⇒ Object 



53
54
55
 
# File 'lib/graphql/remote_loader/loader.rb', line 53

def self.reset_index
  @index = nil
end

.store_context(context) ⇒ Object 



57
58
59
60
 
# File 'lib/graphql/remote_loader/loader.rb', line 57

def self.store_context(context)
  @context ||= {}
  @context.merge!(context.to_h)
end

Instance Method Details

#query(query_string) ⇒ Object

Given a query string, return a response JSON

Raises:

  • (NotImplementedError) 


63
64
65
66
 
# File 'lib/graphql/remote_loader/loader.rb', line 63

def query(query_string)
  raise NotImplementedError,
    "RemoteLoader::Loader should be subclassed and #query must be defined"
end