1. Goodies and Gimmicks for a user-friendly access to Grids
Mathias Stümpert (Karlsruhe Institute of Technology)
Ariel Garcia (Karlsruhe Institute of Technology)
March 18th, 2008
EclipseCon 2008
Santa Clara

2. Topics
g-AAI - Authentication and Authorization
g-EFS - Data management with EFS
g-PRM - The Problem Reporting Mechanism

3. g-AAI - Authentication and Authorization Infrastructure
Provides an abstraction layer and an extension point for plugging in any type of authentication token
Provides tokens for:
Globus proxies (X509)
VOMS proxies (X509 with extensions)
GRIA key stores
Open for other tokens (SSH, Shibboleth...)
Provides mechanism for creating tokens on demand:
of a specific type and
with specific parameters
Tokens are stored (not persistent!) for re-use
Common graphical user interface for all tokens

4. g-AAI - Workflow Requesting a token with an AuthTokenRequest
that contains an IAuthenticationTokenDescription
which is specific for an IAuthenticationToken
and holds the parameters of the token to be created.
The AuthTokenProvider
looks up all existing tokens in the AuthTokenManager
and returns a matching token or asks the user to create a new one with the AuthTokenWizard if no matching token could be found.

5. g-EFS - Data management with g-Eclipse
One of the main use-cases for Grids is data management
g-Eclipse integrates existing EFS implementations into its views:
browse an EFS
copy&paste/drag&drop data among different EFSes
Create/delete files/folders
Open, edit and save back files
g-Eclipse itself implements EFS for
GridFTP/GSIFTP (Globus middleware)
SRM (gLite middleware)
LFC (gLite middleware)

6. g-EFS - The Exploring Perspective

7. g-EFS - The Connection Wizard
Local Connection
Remote (GSIFTP) Connection

8. g-PRM - The traditional ways
Accessing Grids is difficult and error-prone
Error messages are often rather cryptic
Traditional error reporting (exception handling) supports only plain descriptive texts as error messages
Eclipse way uses CoreException and IStatus which already gives more information about
the type of the error (warning, error, ...)
details of the error (error code)
where the error happened (plug-in ID)
contexts (MultiStatus)

9. g-PRM - The g-Eclipse way
g-Eclipse deals with problems, not with errors
Therefore g-Eclipse defines the ProblemException, which
inherits from CoreException - i.e. supports IStatus - and
may have an associated IProblem
An IProblem is comprised of:
a description (String)
one or more optional reasons (String)
one or more optional solutions (ISolution)
an optional mailto-field for sending error reports
an exception, plug-in id, etc. (i.e. IStatus)

10. g-PRM - Offering solutions for problems
Solutions are comprised of
a description (String) and
an optional solver (ISolver)
Solutions are either active (if a solver is defined) or passive
Passive solutions are just plain text giving the user hints how to solve a problem
Active solutions can trigger an action in the UI that solves or at least may help the user to solve a problem

11. g-PRM - Defining problems and solutions
Problems and solutions may be defined either
programmatically, i.e. via the API, or
declaratively, i.e. with the help of an extension point
The extension point allows to
specify problems
specify solutions
make solutions active by either
specifying an ISolver for the solution or by
tagging the solution with a predefined solver tag
Predefined tags exist for
opening a preference page
opening a view
assign solutions to a problem and vice versa. This means that solutions may be re-used by different problems

12. g-PRM - Features Problems and solutions are defined in plugin.xml
Problems are propagated with an exception
Already defined problems can be used by other plug-ins
Solutions can be added to existing problems
in code by catching a ProblemException and adding a solution to the problem
from other plug-ins by defining a solution and linking it to the problem (backward-link)
Reasons can be added to existing problems
in code by catching a ProblemException and adding a reason to the problem.

13. g-PRM - How it looks like

14. g-PRM - How it looks like