Class: Mara::Query

Inherits:
Object
  • Object
show all
Includes:
DynamoHelpers
Defined in:
lib/mara/query.rb

Overview

Perform calls to DynamoDB for fetching

Author:

  • Maddie Schipper

Since:

  • 1.0.0

Defined Under Namespace

Classes: Result

Class Method Summary collapse

Methods included from DynamoHelpers

included

Class Method Details

.get_item(query_params) ⇒ Mara::Query::Result

Perform a single item get request by the primary key.

Parameters:

  • query_params (Hash) —

    The query items.

Returns:

Since:

  • 1.0.0



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# File 'lib/mara/query.rb', line 39

def get_item(query_params)
  client, table_name = config_params(query_params)
  primary_key = query_params.fetch(:key)
  projection_expression = query_params.fetch(:projection_expression, nil).presence

  params = {
    key: primary_key,
    table_name: table_name,
    return_consumed_capacity: 'TOTAL',
    projection_expression: projection_expression
  }

  result =  Mara.instrument('get_item', params) do
    client.get_item(params)
  end

  return nil if result.item.nil?

  item = format_item(result.item)
  cc = calculate_consumed_capacity(result.consumed_capacity, table_name)

  Result.new(
    [item],
    cc
  )
end