Module Mongo::Retry provides retry support on mongo connection or operation failures

mongo_retry.rb

# Module Mongo::Retry provides retry support on mongo connection or operation failures   
#   
# @note Bit enhanced replacement of Mongo::Retryable (included Mongo Ruby Driver since 2.1.0)
#   
# @see https://jira.mongodb.org/browse/SERVER-14322   
# @see https://gist.github.com/bhbryant/1230938   
# @see https://www.compose.com/articles/your-drivers-are-not-magic-testing-your-application-for-high-availability/    
# @see https://gist.github.com/reidmorrison/1498297   
# @see https://github.com/reidmorrison/mongo_ha   
# @see https://github.com/mongodb/mongo-ruby-driver/blob/master/lib/mongo/retryable.rb    
#  
# @note Mongo::Retryable has much more robust implementation since 2.5.0
#
# @see https://jira.mongodb.org/projects/RUBY/issues/RUBY-1229
# @see https://github.com/mongodb/mongo-ruby-driver/commit/9940a93a79ba82a195c5ab8f8454d8781cd7db97#diff-6bc98b755c989c59b44ca84ce384e457
#
module Mongo::Retry   
  # Wrapper to rescue Mongo::ConnectionFailure exeptions which is recommended by official   
  # documentation when working with replica sets.   
  #   
  # @example Usage    
  #   retry_on_connection_failure(10) do    
  #     collection.find(id: id)   
  #   end   
  #   
  # @param [Integer] max_retries: 60 The maximum retries of the wrapped operation   
  # @param [Float] wait_sec: 0.5 The waiting time in seconds  before next retry   
  #   
  # @return The result of the block   
  #   
  def retry_on_connection_failure(max_retries: 40, wait_sec: 0.5)   
    retries = 0   
    begin   
      yield   
    rescue Mongo::ConnectionFailure => ex   
      retries += 1    
      raise ex if retries > max_retries   
      Kernel.sleep(wait_sec)    
      retry   
    end   
  end   
     
  # Wrapper to rescue Mongo::OperationFailure exeptions and retry the command.    
  #   
  # @example Retry find_and_modify command which often fails with Mongo::OperationFailure   
  #   retry_on_operation_failure(max_retries: 30, wait_sec: 0.1) do   
  #     collection.find_and_modify({    
  #       query: { '_id' => id },   
  #       update: { '$set' => attributes },   
  #     })    
  #   end   
  #   
  # @param [Integer] max_retries: 60 The maximum retries of the wrapped operation   
  # @param [Float] wait_sec: 0.1 The waiting time in seconds  before next retry   
  #   
  # @return The result of the block   
  #   
  def retry_on_operation_failure(max_retries: 1, wait_sec: 0.0)   
    retries = 0   
    begin   
      yield   
    rescue Mongo::OperationFailure => ex    
      retries += 1    
      raise ex if retries > max_retries   
      Kernel.sleep(wait_sec)    
      retry   
    end   
  end   
     
  # Wrapper to rescue Mongo::ConnectionFailure as well as Mongo::OperationFailure exeptions and   
  # retry the command.    
  #   
  # @example Retry find_and_modify command which often fails with Mongo::OperationFailure   
  #   retry_on_mongo_failure(op_retries: 2) do    
  #     collection.find_and_modify({    
  #       query: { '_id' => id },   
  #       update: { '$set' => attributes },   
  #     })    
  #   end   
  #   
  # @param [Integer] max_retries: 60 The maximum retries of the wrapped operation   
  # @param [Float] wait_sec: 0.1 The waiting time in seconds  before next retry   
  #   
  # @return The result of the block   
  #   
  def retry_on_mongo_failure(max_retries: 40, wait_sec: 0.5, op_retries: 5, op_wait_sec: 0.3)   
    retries = 0   
    begin   
      yield   
    rescue Mongo::OperationFailure => ex    
      retries += 1    
      raise ex if retries > op_retries    
      Kernel.sleep(op_wait_sec)   
      retry   
    rescue Mongo::ConnectionFailure => ex   
      retries += 1    
      raise ex if retries > max_retries   
      Kernel.sleep(wait_sec)    
      retry   
    end   
  end        
end