Class: Gcloud::Datastore::Key

Inherits:
Object
  • Object
show all
Defined in:
lib/gcloud/datastore/key.rb

Overview

# Key

Every Datastore record has an identifying key, which includes the record’s entity kind and a unique identifier. The identifier may be either a key name string, assigned explicitly by the application, or an integer numeric ID, assigned automatically by Datastore.

Examples:

key = Gcloud::Datastore::Key.new "User", "[email protected]"

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(kind = nil, id_or_name = nil) ⇒ Gcloud::Datastore::Dataset::Key

Create a new Key instance.

Examples:

key = Gcloud::Datastore::Key.new "User", "[email protected]"

Parameters:

  • kind (String) (defaults to: nil) —

    The kind of the Key. This is optional.

  • id_or_name (Integer, String) (defaults to: nil) —

    The id or name of the Key. This is optional.



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# File 'lib/gcloud/datastore/key.rb', line 90

def initialize kind = nil, id_or_name = nil
  @kind = kind
  if id_or_name.is_a? Integer
    @id = id_or_name
  else
    @name = id_or_name
  end
end

Instance Attribute Details

#dataset_id ⇒ String

The dataset_id of the Key.

Examples:

require "gcloud"

gcloud = Gcloud.new "my-todo-project",
                    "/path/to/keyfile.json"

dataset = gcloud.datastore
entity = dataset.find "User", "[email protected]"
entity.key.dataset_id #=> "my-todo-project"

Returns:

  • (String) 


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# File 'lib/gcloud/datastore/key.rb', line 59

def dataset_id
  @dataset_id
end

#id ⇒ Integer?

The id of the Key.

Examples:

key = Gcloud::Datastore::Key.new "User", 123456
key.id #=> 123456

Returns:

  • (Integer, nil) 


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# File 'lib/gcloud/datastore/key.rb', line 127

def id
  @id
end

#kind ⇒ String

The kind of the Key.

Examples:

key = Gcloud::Datastore::Key.new "User"
key.kind #=> "User"
key.kind = "Task"

Returns:

  • (String) 


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# File 'lib/gcloud/datastore/key.rb', line 42

def kind
  @kind
end

#name ⇒ String?

The name of the Key.

Examples:

key = Gcloud::Datastore::Key.new "User", "[email protected]"
key.name #=> "[email protected]"

Returns:

  • (String, nil) 


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# File 'lib/gcloud/datastore/key.rb', line 157

def name
  @name
end

#namespace ⇒ String?

The namespace of the Key.

Examples:

require "gcloud"

gcloud = Gcloud.new "my-todo-project",
                    "/path/to/keyfile.json"

dataset = gcloud.datastore
entity = dataset.find "User", "[email protected]"
entity.key.namespace #=> "ns~todo-project"

Returns:

  • (String, nil) 


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# File 'lib/gcloud/datastore/key.rb', line 76

def namespace
  @namespace
end

#parent ⇒ Key?

The parent of the Key.

Examples:

require "gcloud"

gcloud = Gcloud.new
dataset = gcloud.datastore

user = dataset.find "User", "[email protected]"
query = dataset.query("List").
  ancestor(user.key)
lists = dataset.run query
lists.first.key.parent #=> Key("User", "[email protected]")

Returns:



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# File 'lib/gcloud/datastore/key.rb', line 191

def parent
  @parent
end

Class Method Details

.from_proto(proto) ⇒ Object 



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# File 'lib/gcloud/datastore/key.rb', line 243

def self.from_proto proto
  # Disable rules because the complexity here is neccessary.
  key_proto = proto.dup
  key = Key.new
  proto_path_element = Array(key_proto.path_element).pop
  if proto_path_element
    key = Key.new proto_path_element.kind,
                  proto_path_element.id || proto_path_element.name
  end
  if key_proto.partition_id
    key.dataset_id = key_proto.partition_id.dataset_id
    key.namespace  = key_proto.partition_id.namespace
  end
  if Array(key_proto.path_element).count > 0
    key.parent = Key.from_proto(key_proto)
  end
  # Freeze the key to make it immutable.
  key.freeze
  key
end

Instance Method Details

#complete? ⇒ Boolean

Determine if the key is complete. A complete key has either an id or a name.

Inverse of #incomplete?

Returns:

  • (Boolean) 


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# File 'lib/gcloud/datastore/key.rb', line 215

def complete?
  !incomplete?
end

#incomplete? ⇒ Boolean

Determine if the key is incomplete. An incomplete key has neither an id nor a name.

Inverse of #complete?

Returns:

  • (Boolean) 


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# File 'lib/gcloud/datastore/key.rb', line 224

def incomplete?
  kind.nil? || (id.nil? && (name.nil? || name.empty?))
end

#path ⇒ Array<Array<(String, String)>>

Represent the Key’s path (including parent) as an array of arrays. Each inner array contains two values, the kind and the id or name. If neither an id or name exist then nil will be returned.

Examples:

key = Gcloud::Datastore::Key.new "List", "todos"
key.parent = Gcloud::Datastore::Key.new "User", "[email protected]"
key.path #=> [["User", "[email protected]"], ["List", "todos"]]

Returns:

  • (Array<Array<(String, String)>>) 


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# File 'lib/gcloud/datastore/key.rb', line 205

def path
  new_path = parent ? parent.path : []
  new_path << [kind, (id || name)]
end

#to_proto ⇒ Object 



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# File 'lib/gcloud/datastore/key.rb', line 230

def to_proto
  Proto::Key.new.tap do |k|
    k.path_element = path.map do |pe_kind, pe_id_or_name|
      Proto.new_path_element pe_kind, pe_id_or_name
    end
    k.partition_id = Proto.new_partition_id dataset_id, namespace
  end
end