App Engine Python SDK  v1.6.9 rev.445
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Public Member Functions | Public Attributes | Properties | List of all members
google.appengine.ext.mapreduce.model.MapperSpec Class Reference
Inheritance diagram for google.appengine.ext.mapreduce.model.MapperSpec:
google.appengine.ext.mapreduce.json_util.JsonMixin

Public Member Functions

def __init__
 
def get_handler
 
def input_reader_class
 
def output_writer_class
 
def to_json
 
def __str__
 
def from_json
 
def __eq__
 
- Public Member Functions inherited from google.appengine.ext.mapreduce.json_util.JsonMixin
def to_json_str
 
def from_json_str
 

Public Attributes

 handler_spec
 
 input_reader_spec
 
 output_writer_spec
 
 shard_count
 
 params
 

Properties

 handler = property(get_handler)
 

Detailed Description

Contains a specification for the mapper phase of the mapreduce.

MapperSpec instance can be changed only during mapreduce starting process,
and it remains immutable for the rest of mapreduce execution. MapperSpec is
passed as a payload to all mapreduce tasks in JSON encoding as part of
MapreduceSpec.

Specifying mapper handlers:
  * '<module_name>.<class_name>' - __call__ method of class instance will be
    called
  * '<module_name>.<function_name>' - function will be called.
  * '<module_name>.<class_name>.<method_name>' - class will be instantiated
    and method called.

Constructor & Destructor Documentation

def google.appengine.ext.mapreduce.model.MapperSpec.__init__ (   self,
  handler_spec,
  input_reader_spec,
  params,
  shard_count,
  output_writer_spec = None 
)
Creates a new MapperSpec.

Args:
  handler_spec: handler specification as string (see class doc for
details).
  input_reader_spec: The class name of the input reader to use.
  params: Dictionary of additional parameters for the mapper.
  shard_count: number of shards to process in parallel.

Properties:
  handler_spec: name of handler class/function to use.
  input_reader_spec: The class name of the input reader to use.
  params: Dictionary of additional parameters for the mapper.
  shard_count: number of shards to process in parallel.
  output_writer_spec: The class name of the output writer to use.

Member Function Documentation

def google.appengine.ext.mapreduce.model.MapperSpec.from_json (   cls,
  json 
)
Creates MapperSpec from a dict-like object.
def google.appengine.ext.mapreduce.model.MapperSpec.get_handler (   self)
Get mapper handler instance.

This always creates a new instance of the handler. If the handler is a
callable instance, MR only wants to create a new instance at the
beginning of a shard or shard retry. The pickled callable instance
should be accessed from TransientShardState.

Returns:
  handler instance as callable.
def google.appengine.ext.mapreduce.model.MapperSpec.input_reader_class (   self)
Get input reader class.

Returns:
  input reader class object.
def google.appengine.ext.mapreduce.model.MapperSpec.output_writer_class (   self)
Get output writer class.

Returns:
  output writer class object.
def google.appengine.ext.mapreduce.model.MapperSpec.to_json (   self)
Serializes this MapperSpec into a json-izable object.

The documentation for this class was generated from the following file: