Contributing¶

Reporting a bug¶

You can report a bug on the issue tracker on google code or on the mailing list.

Retrieving the latest code¶

You can check the latest sources with the command:

hg clone https://code.google.com/p/scoop/

Bear in mind that this development code may be partially broken or unfinished. To get a stable version of the code, update to a release tag using hg update <tag name>.

Coding guidelines¶

Most of those conventions are base on Python PEP8.

A style guide is about consistency. Consistency with this style guide is important. Consistency within a project is more important. Consistency within one module or function is most important.

Code layout¶

Same as PEP8.

Imports¶

Standard library imports must be first, followed by SCOOP imports and finally custom modules. Each section should be separated by an empty line as such:

import system

from scoop import futures

import myModule

Whitespace in Expressions and Statements¶

Same as PEP8.

Comments¶

Same as PEP8

Documentation Strings¶

Same as PEP8

Naming Conventions¶

Module: lowercase convention.
Class: CapWords (upper camel case) convention (ie. AnExample).
Function / Procedure: mixedCase (lower camel case) convention. First word should be an action verb.
Variable: lower_case_with_underscores convention. Should be as short possible as.

If a name already exists in the standard library, an underscore is appended to it. (ie. a custom range function could be called range_. A custom type function could be called type_.)

Architecture¶

Communication protocols¶

Here are the message types from the point of view of a broker. Message coming from workers are always from their Task socket.

Message name	Socket	Arguments	Description
INIT	Task		Handshake from a worker: allows a broker to recognize a new worker and propagate the currently shared variables.
CONNECT	Task	Addresses	Notify a broker of the existence of other brokers.
REQUEST	Task		Worker requesting task(s).
TASK	Task	Task	A task (future) to be executed.
REPLY	Task*	Task, Destination	The result of a task to be sent to its parent. Communicated directly between workers if possible.
SHUTDOWN	Info		Request a shutdown of the entire worker pool.
VARIABLE	Info	Key, Value, Source	A worker requested the share of a variable. The broker propagates it to its fellow workers.
TASKEND	Info	askResult, groupID	A collaborative task (scan, reduce, etc.) have ended, memory can be freed on workers.
BROKER_INFO	Info		Propagate information about other brokers to workers.