Recorders¶

class pikos.recorders.abstract_recorder.AbstractRecorder[source]¶

Bases: object

Abstract recorder class.

A recorder is reposnible for storing the record data that are provided by the monitor or profiler. The records are expected to be nametuple-like classes.

prepare(record)[source]¶

Perform any setup required before the recorder is used.

Parameters:	record (NamedTuple) – The record class that is going to be used.

finalize()[source]¶: Perform any tasks to finalize and clean up when the recording has completed.

record(data)[source]¶

Record a measurement.

Parameters:	data (NamedTuple) – An instance of the record class that is going to be used.

class pikos.recorders.csv_recorder.CSVRecorder(stream, filter_=None, **csv_kwargs)[source]¶

Bases: pikos.recorders.abstract_recorder.AbstractRecorder

The CSV Recorder is a simple text based recorder that records the tuple of values using a scv writer.

Private

_filter : callable: Used to check if the set record should be recorded. The function accepts a tuple of the record values and return True is the input sould be recored.
_writer : csv.writer: The writer object is owned by the CSVRecorder and exports the record values according to the configured dialect.
_ready : bool: Singify that the Recorder is ready to accept data.

__init__(stream, filter_=None, **csv_kwargs)[source]¶

Class initialization.

Parameters:	stream (file) – A file-like object to use for output. filter_ (callable) – A callable function that accepts a data tuple and returns True if the input sould be recorded. *csv_kwargs – Key word arguments to be passed to the cvs.writer*.

prepare(record)[source]¶: Write the header in the csv file the first time it is called.

finalize()[source]¶

Finalize the recorder.

A do nothing method.

Raises:	RecorderError – Raised if the method is called without the recorder been ready to accept data.

record(data)[source]¶

Record the data entry when the filter function returns True.

Parameters:	values (NamedTuple) – The record entry.
Raises:	RecorderError – Raised if the method is called without the recorder been ready to accept data.

class pikos.recorders.csv_file_recorder.CSVFileRecorder(filename, filter_=None, **csv_kwargs)[source]¶

Bases: pikos.recorders.csv_recorder.CSVRecorder

A CSVRecorder that creates the stream (i.e. file) for the records.

Private

_filter : callable: Used to check if the set record should be recorded. The function accepts a tuple of the record values and return True is the input sould be recored.
_writer : csv.writer: The writer object is owned by the CSVRecorder and exports the record values according to the configured dialect.
_ready : bool: Singify that the Recorder is ready to accept data.
_filename : string: The name and path of the file to be used for output.
_file : file: The file object where records are stored.

__init__(filename, filter_=None, **csv_kwargs)[source]¶

Class initialization.

Parameters:	filename (string) – The file path to use. filter_ (callable) – A callable function that accepts a data tuple and returns True if the input sould be recorded. Default is None. *csv_kwargs – Key word arguments to be passed to the cvs.writer*.

prepare(record)[source]¶: Open the csv file and write the header in the csv file.

finalize()[source]¶

Finalize the recorder.

Raises:	RecorderError – Raised if the method is called without the recorder been ready to accept data.

class pikos.recorders.list_recorder.ListRecorder(filter_=None)[source]¶

Bases: pikos.recorders.abstract_recorder.AbstractRecorder

The ListRecorder is simple recorder that records the tuple of values in memory as a list.

Public

records : list: List of records. The Recorder assumes that the record method is provided with a tuple and accumulates all the records in a list.

Private

_filter : callable: Used to check if the data entry should be recorded. The function accepts a namedtuple record and return True is the input sould be recored.

__init__(filter_=None)[source]¶

Class initialization.

Parameters:	filter_ (callable) – A callable function to filter out the data entries that are going to be recorded.

prepare(record)[source]¶: Prepare the recorder to accept data.

Note

nothing to do for the ListRecorder.

finalize()[source]¶: Finalize the recorder.

Note

nothing to do for the ListRecorder.

ready[source]¶: Is the recorder ready to accept data?

record(data)[source]¶

Record the data entry when the filter function returns True.

Parameters:	data (NamedTuple) – The record entry.

class pikos.recorders.text_stream_recorder.TextStreamRecorder(text_stream, filter_=None, formatted=False, auto_flush=False)[source]¶

Bases: pikos.recorders.abstract_recorder.AbstractRecorder

The TextStreamRecorder is simple recorder that formats and writes the records directly to a stream.

Private

_stream : TextIOBase: A text stream what supports the TextIOBase interface. The Recorder will write the values as a single line.
_filter : callable: Used to check if the set record should be recorded. The function accepts a tuple of the record values and return True is the input should be recorded.
_template : str: A string (using the Format Specification Mini-Language) to format the set of values in a line. It is constructed when the prepare method is called.
_auto_flush : bool: A bool to enable/disable automatic flushing of the string after each record process.
_ready : bool: Signify that the Recorder is ready to accept data.

__init__(text_stream, filter_=None, formatted=False, auto_flush=False)[source]¶

Class initialization.

Parameters:

text_stream (TextIOBase) – A text stream what supports the TextIOBase interface.
filter_ (callable) – A callable function that accepts a data tuple and returns True if the input sould be recorded.
formatted (Bool) – Use the predefined formatting in the records. Default value is false.
auto_flush (Bool) – When set the stream buffer is always flushed after each record process. Default value is False.

prepare(record)[source]¶

Prepare the recorder to accept data.

Parameters:	data (NamedTuple) – An example record to prepare the recorder and write the header to the stream.

finalize()[source]¶

Finalize the recorder

A do nothing method.

Raises:	RecorderError – Raised if the method is called without the recorder been ready to accept data.

record(data)[source]¶

Rerord the data entry when the filter function returns True.

Parameters:	data (NamedTuple) – The record entry.
Raises:	RecorderError – Raised if the method is called without the recorder been ready to accept data.

Note

Given the value of _auto_flush the recorder will flush the stream buffers after each record.

class pikos.recorders.text_file_recorder.TextFileRecorder(filename, filter_=None, formatted=False, auto_flush=False)[source]¶

Bases: pikos.recorders.text_stream_recorder.TextStreamRecorder

The TextStreamRecorder that creates the file for the records.

Private

_stream : TextIOBase: A text stream what supports the TextIOBase interface. The Recorder will write the values as a single line.
_filter : callable: Used to check if the set record should be recorded. The function accepts a tuple of the record values and return True is the input should be recorded.
_template : str: A string (using the Format Specification Mini-Language) to format the set of values in a line. It is constructed when the prepare method is called.
_auto_flush : bool: A bool to enable/disable automatic flushing of the string after each record process.
_ready : bool: Signify that the Recorder is ready to accept data.
_filename : string: The name and path of the file to be used for output.

__init__(filename, filter_=None, formatted=False, auto_flush=False)[source]¶

Class initialization.

Parameters:

filename (string) – The file path to use.
filter_ (callable) – A callable function that accepts a data tuple and returns True if the input sould be recorded. Default is None.
formatted (Bool) – Use the predefined formatting in the records. Default value is false.
auto_flush (Bool) – When set the stream buffer is always flushed after each record process. Default value is False.

prepare(record)[source]¶: Open the file and write the header.

finalize()[source]¶

Finalize the recorder.

Raises:	RecorderError – Raised if the method is called without the recorder been ready to accept data.

class pikos.recorders.zeromq_recorder.ZeroMQRecorder(zmq_host='127.0.0.1', zmq_port=9001, filter_=None, wait_for_ready=True, **kwargs)[source]¶

Bases: pikos.recorders.abstract_recorder.AbstractRecorder

The ZeroMQ Recorder is a recorder that publishes each set of values on a 0MQ publish socket.

Private

_filter : callable: Used to check if the set record should be recored. The function accepts a tuple of the record values and return True is the input sould be recored.
_ready : bool: Singify that the Recorder is ready to accept data. Please use the Recorder.ready property

__init__(zmq_host='127.0.0.1', zmq_port=9001, filter_=None, wait_for_ready=True, **kwargs)[source]¶

Class initialization.

Parameters:	filter_ (callable) – A callable function that accepts a data tuple and returns True if the input sould be recorded.

prepare(record)[source]¶: Write the header in the csv file the first time it is called.

finalize()[source]¶: Signal that recording has ended.

ready[source]¶: Is the recorder ready to accept data?

record(record)[source]¶: Rerord entry onlty when the filter function returns True.