Concepts:
Workspaces
SWEN 5135 Configuration Management
Topics
Workspaces refer to ‘private’ areas where developers can implement and
test code in accordance with the project’s adopted standards in relative
isolation from other developers. The Configuration Manager needs to create a
workspace environment for each developer on the project.
A workspace provides each developer with a consistent, flexible, inexpensive,
and reproducible environment that selects and presents the appropriate version
of each file. The workspace needs to be able to provide fine-grained control
over both sharing and isolation. This is required because in most projects,
developers need to stay isolated from changes made by others; but at the same
time, they must be able to unit-test their changes with changes made by certain
other developers.
When performing maintenance on older releases, a developer needs to be able
to see older versions, binaries, documents, tests, tools, and other objects. In
this case the workspace serves as a ‘time machine’, making everything in the
environment, not just the sources, appear as it did in the past.
Each developer’s workspace needs to be isolated, for purposes of editing,
compiling, testing and debugging. However, the isolation of the workspace should
be relative and not absolute:
- Others should be able to track a developers work, and selectively
integrate it into their own.
- Others should be able to shut out, until a subsequent integration period,
those changes that may prove destabilizing to their own work.
A workspace can be completely private to an individual developer, or shared
among a team of developers over a network.
In addition to providing access to source versions, a workspace needs to
provide private (isolated) storage for files generated during software
development:
- Working (checked-out) versions of source files,
- Executables,
- Other workspace private objects – source code, test subdirectories, and
test data files.
A workspace’s private storage would be typically located within a developer’s
home directory on a workstation. A workspace shared by a group of developers
might have its private storage area located on a central file server. However,
the actual location of the private storage is largely irrelevant. From the
developer’s point of view the workspace’s private storage should be appear
to be fully integrated.
The figure above illustrates the notion of private and
integration workspaces in the overall context of the CM Cube.
Working configurations (workspace profiles) refer to particular subsystems
that make up a working set for the project. A working set is a
list of specific versions of subsystems that must be
referenced, or modified, to implement a piece of work. This list may represent
the entire system or a subset.
A view provides access to a set of files in the project repository. Moreover,
a view provides access to an appropriate set of versions of those files:
- A new development view may provide access to the most recent versions of
the files.
- Another new development view may provide access to the versions being used
by a team working on a new user interface for your product.
- A maintenance view may provide access to the versions of the files that
were used to build a given release of the product.
A workspace, sometimes also called a view, allows developers to make and test
changes in private before sharing the modifications with the rest of the team.
There are two types of views:
- Snapshot Views, and
- Dynamic Views.
A snapshot view provides the developer with a stable, unchanging
working environment. It is analogous to a computer directory tree. A snapshot
view is populated with copies of the appropriate versions of files from one or
more project repositories. Some people use the term "sandbox" for such
a directory tree. When a developer wants to see changes made by other team
members, she updates her view. This style of working is characterized as a pull
model as it relies on actively pulling in the relevant information, rather than
it being immediately available through automatic refresh mechanisms.
A dynamic view is a virtual data structure as it appears to contain
all the development data. Dynamic views do not make local copies of files, but
rely on over the network immediate updating. Dynamic views may be the best
choice in the following situations:
- There is limited client-side disk space
- You want to take advantage of derived object sharing
- The development team must work with the latest versions of the code. This
feature is particularly useful for integration that requires the latest
version of any given software.
Copyright
© 1987 - 2001 Rational Software Corporation
| 
Disciplines >
Configuration & Change Management >
Concepts >
