Automation - The Practice of Cloud System Administration - page 265

12.7.3 Software Packaging
Software, once developed, should be distributed in packages. Although this topic was dis-
cussed in Section 9.6 , we raise the issue again here because the same operations people
who maintain a service delivery platform often distribute their own software tools by ad
hoc means.
Distributing your own software via packages enables you to take advantage of all the
systems used to keep software up-to-date. Without this capability, operational tools end up
being copied manually. The result is many systems, all out of date, and all the problems
that can bring.
Ideally the packages should go through the same development, beta, and production
phases as other software. (See Chapter 9 . )
12.7.4 Style Guides
A style guide is a standard indicating how source code should be formatted and which lan-
guage features are encouraged, discouraged, or banned. Having all code conform to the
same style makes it easier to maintain the code and raises code quality. It sets a high bar
for quality and consistency, raising standards for the entire team. A style guide also has a
mentoring effect on less experienced people.
Typicallyprogrammersspendthevastmajorityoftheirtimemodifyingcodeandadding
features to existing code. Rarely do we have the opportunity to write a new program from
scratch and be the sole maintainer for its entire life. When we work together as a team,
it becomes critical to be able to look at a file for the first time and assimilate its contents
quickly. This enhances productivity. When we write code that conforms to the style guide,
we pay this productivity forward.
Style Guide Basics
Style guides make both formatting and feature recommendations. Formatting recommend-
ations include specifying how indenting and whitespace are used. For example, most com-
panies standardize on indenting with four (or less commonly two) spaces instead of tabs,
eliminatingextrablanklinesattheendoffilesorwhitespaceattheendoflines,andplacing
a single blank line between functions, and possibly two blank lines before major sections
or classes.
Style guides prescribe more than just aesthetics. They also recommend particular lan-
guage features over others, and often outright ban certain language features that have
proved to be difficult to support. Languages often have two ways of doing something, and
the style guide will select which is to be used. Languages may also have features that are