introduction to access grid development
DESCRIPTION
Introduction to Access Grid Development. Agenda. Architecture AG Application Basics AccessGrid module overview Example application Exercises. Architecture. Technologies. Python wxPython pyGlobus SOAP (SOAPpy) pyOpenSSL. AG Application Basics. - PowerPoint PPT PresentationTRANSCRIPT
Access Grid Workshop – APAC ‘05
Introduction to Access Grid Development
Access Grid Workshop – APAC ‘05
Agenda
• Architecture• AG Application Basics• AccessGrid module overview• Example application• Exercises
Access Grid Workshop – APAC ‘05
Architecture
Access Grid Workshop – APAC ‘05
Technologies
• Python• wxPython• pyGlobus• SOAP (SOAPpy)• pyOpenSSL
Access Grid Workshop – APAC ‘05
AG Application Basics
An Access Grid client application will perform (at least) these steps:
• Create an application instance• Initialize application • Create an interface wrapper• Call methods on the interface
wrapper
Access Grid Workshop – APAC ‘05
AG Application Basics
• The core of an AG application is an instance of AccessGrid.Toolkit.Application
AppBase
Application
CmdlineApplication WXGUIApplication
Service
Access Grid Workshop – APAC ‘05
AG Application Basics
• Distinguished between GUI and non-GUI applications to generalize user interactions (for example, prompt for passphrase, error reporting)– CmdlineApplication
• Examples: BridgeServer, VenueServer, AGNodeService
– WXGUIApplication• Examples: VenueClient,
VenueManagement, NodeManagement
Access Grid Workshop – APAC ‘05
Application Initialization
• Create AG application instance• Initialize application
– Verify certificate repository– Load default certificate– Create proxy certificate– Configure Globus environment
app = CmdlineApplication.instance()app.Initialize(appName)
• appName is used in logfile name
Access Grid Workshop – APAC ‘05
Argument Processing
• Standard Python module optparse is integrated into toolkit
• Add option to application before initialization
• Access options post-initialization
app.AddCmdLineOption(optparse.Option(‘-u’,’—url’,
dest=‘url’))
app.Initialize(‘SampleApp’)
url = app.GetOption(‘url’)
Access Grid Workshop – APAC ‘05
Standard Toolkit Arguments
• The toolkit adds some options to all applications
• Available options can be viewed with ‘-h’ or –help
• Examples-d (turn on debug)-l <logFileName>--logfilesize <size> --numlogfiles <num> (rollover log files)
Access Grid Workshop – APAC ‘05
Logging
• Standard Python module logging is integrated into AccessGrid toolkit
• Multiple logging levels are defined (see logging module documentation)– CRITICAL, ERROR, WARNING, INFO, DEBUG
• Logging levels can be controlled for individual components in an application
• Application will create appName.log (appName is from app.Initialize) in Log directory:– Windows: %APPDATA%\AccessGrid\Logs– Linux/OSX: $HOME/.AccessGrid/Logs
• Logging calls in code will appear in logfile, according to call and current logging level– log.debug(‘this is debug logging text’)
Access Grid Workshop – APAC ‘05
AccessGrid Module Overview
• AccessGrid– Core toolkit code
• AccessGrid.Security– CertificateManager, CertificateRepository, etc.– AuthorizationManager, Role, Action, etc.
• AccessGrid.Platform– Platform-specific code
• Config.{SystemConfig,UserConfig,etc.}• ProcessManager
• AccessGrid.hosting– SOAP implementation adapters
Access Grid Workshop – APAC ‘05
AccessGrid Module API Documentation
Access Grid Workshop – APAC ‘05
Interfaces and InterfaceWrappers
• Described in online API documentation• Interface wrappers are defined in
individual modules– For example, AccessGrid.Venue.VenueIW
• IW (and I) class methods handle serialization/deserialization of data types from SOAP implementation domain to AG application domain
Access Grid Workshop – APAC ‘05
Available InterfaceWrappers
• VenueIW• VenueServerIW• VenueClientIW• AGNodeServiceIW• AGServiceManagerIW• AGServiceIW• AuthorizationManagerIW• SharedApplicationIW• NetworkServiceIW
Access Grid Workshop – APAC ‘05
VenueIW
Access Grid Workshop – APAC ‘05
Types
• Many types are found in Descriptions.py– StreamDescription– ApplicationDescription
• Others are found in their own modules– ClientProfile– AGParameter– Capability
Access Grid Workshop – APAC ‘05
AG Applications
An Access Grid client application will perform (at least) these steps:
• Create an application instance• Initialize application • Create an interface wrapper• Call methods on the interface
wrapper
Access Grid Workshop – APAC ‘05
Example: GetClients.py
#!/usr/bin/python2
import sysfrom AccessGrid.Toolkit import CmdlineApplicationfrom AccessGrid.Venue import VenueIW
url = sys.argv[1]
# Create and initialize applicationapp = CmdlineApplication()app.Initialize('qwe')# Create venue interface wrappervenue = VenueIW(url)
# Get clients from venue and processclientList = venue.GetClients()for client in clientList: print client
Access Grid Workshop – APAC ‘05
Example: GetClients.py
python GetClients.py https://vv2.mcs.anl.gov:9000/Venues/default
Profile Type: userName: Tom UramEmail: [email protected] Number: Location: Chicago, ILVenue Client URL:
https://wormtongue.mcs.anl.gov:11000/VenueClientPublic ID: 00000102220e6208008c00dd0022004754dHome Venue:
https://vv2.mcs.anl.gov:9000/Venues/default
Access Grid Workshop – APAC ‘05
Example: GetClients.py
• Check logfile GetClients.log
Access Grid Workshop – APAC ‘05
Notes
• Online workshop materials:http://www.mcs.anl.gov/fl/research/accessgrid/documentation/tutorial/AGTk_2.4
• Online developer documentation (including API reference):
http://www.mcs.anl.gov/fl/research/accessgrid/software/developer.html
• OSX users will need to source an environment file to run code in a terminal– /Applications/AccessGridToolkit.app/Contents/
Resources/setupenv.sh
Access Grid Workshop – APAC ‘05
Exercise: GetStreams.py
• Modify GetClients.py to call GetStreams instead of GetClients
• Return value is a list of Descriptions.StreamDescription
Access Grid Workshop – APAC ‘05
Exercise: GetUsers.py
• Modify GetClients.py to call VenueClientIW.GetUsers
• Return value is a list of ClientProfile
Access Grid Workshop – APAC ‘05
Access Grid Workshop – APAC ‘05