discovery the p2 api (updated to indigo)

Discovering the p2 API

Pascal Rapicault

Sonatype, p2 Lead

© Sonatype, inc. All right reserved. Made available under Creative Commons Att. Nc Nd 2.5.license 1

Who are the p2 committers?


History

• 3.4 / 3.5 provisional API

• 3.6 / Helios - first official release of the API

• 3.7 / Indigo - full backward compatibility


What’s new in 3.7?

• API– New features to ease p2 consumption– Simplification for RCP use case– Simpler Headless API for simple cases

• SPI– Pluggable transport

• Code– Memory consumption improvements– Inter-process locking of local repositories– …


3 levels of API

• Graphical User Interface

• Headless Operations

• Core APIs + SPIs


Graphical User Interface

• GUI is SWT-based and designed to be reused in RCP / Eclipse applications.

• Ease of reuse:– Feature org.eclipse.equinox.p2.rcp.feature

• The p2.ui.sdk bundle provides SDK like UI for reuse in RCP.

– Compose from the p2.ui bundle• Add extensions to hook where you want

org.eclipse.equinox.p2.ui

org.eclipse.equinox.p2.ui.sdk


Graphical User Interface


Reusing individual UI elements

• Most the pages / wizards can be reused

– Installed dialog

– Repository management

– License manager

– Install/Update/Uninstall wizard


o.e.e.p2.ui.InstalledSoftwarePage

o.e.e.p2.ui.RepositoryManipulationPage

o.e.e.p2.ui.AcceptLicensesWizardPage

o.e.e.p2.ui.ProvisioningUtil#open*Wizard


Tweaking the existing UI

• The Policy class

– Show / hide repository selection

– Drill down

– Show categories

– Content of the restart dialog

– …


org.eclipse.equinox.p2.ui.Policy


Tweaking the existing UI


Extension / discovery UI


- Simpler for the end user- Nice icons

*Not API*

org.eclipse.equinox.p2.discovery

o.e.e.i.p2.disc….RepositoryDiscoveryStrategy

More on UI reuse

• See examples on the p2 wiki

– http://wiki.eclipse.org/Equinox/p2/Examples

• Talk on the p2 UI

– http://www.eclipsecon.org/2010/sessions/?page=sessions&id=1205


3 levels of API





Minimal headless p2

• A “relatively” minimal headless p2 is available:

– org.eclipse.equinox.p2.core.feature

– Provide enough to install / update / uninstall

• A smaller subset can be created, but it is too specific (e.g. w/o ECF, w/o http client, w/o operations, etc.)


Headless operations

• High level operations to install / update / uninstall

• Focused on the Eclipse / OSGi use cases

• Encapsulates:– Dependency resolution

– Download

– Modification of the system

– Restart

org.eclipse.equinox.p2.operations

org.eclipse.equinox.p2.operations


Headless operations example

InstallOperation op = OperationHelper.create***Operation(iusToInstall, repoList, new

NullProgressMonitor());

if (op.resolveModal(newNullProgressMonitor()).isOK())

op.getProvisioningJob(newNullProgressMonitor()).schedule();


New in 3.7. This API only works for the running instance (which is the case most of the time).To modify another instance, you need to use the InstallOperation directly.

3 levels of API





Core concepts

profile registry/profile

repository

installable unit/metadata

agent

planner

engine

query/queryable


TransportsHttp/Https

File system

Volume

Repositoriesp2

Update Site

Engine

Eclipse/OSGi

Native/OS

Planner/Director

Profile registryRuntimes

Provisioning operation requested

Metadata fetched and constraints analyzed

IU install, uninstall, update operations

Artifact availability and mirroring

Mirroring

Data transfer

IUs configured into runtimes

Profile updated

Metadata repo Artifact repo


Core concepts

How do I get an IU?

• IUs can be obtained from

– Querying the metadata repository

– Querying the profile

– Querying …

– Programmatically createdorg.eclipse.equinox.p2.metadata

org.eclipse.equinox.p2.metadata.MetadataFactory


Queries / QueryableHow do I query?

• What is queryable?– Almost everything is queryable (repository, repository

manager, profile, …)

• How do I create a query?– QueryUtil.create*

– Domain specific queries (e.g. in eclipse.touchpoint)

– p2 QL, p2-specific query language• http://wiki.eclipse.org/Query_Language_for_p2

org.eclipse.equinox.p2.query.IQueryable

org.eclipse.equinox.p2.query.QueryUtil

org.eclipse.equinox.p2.metadata

org.eclipse.equinox.p2.ql© Sonatype, inc. All right reserved. Made available under Creative Commons Att. Nc Nd 2.5.license 21

The repository managerHow do I get a repository?

• Artifact / metadata repository manager• Addition / removal of repositories• Enable / disable repositories• Load

• Artifact / metadata repository• Add• Remove• Query

org.eclipse.equinox.p2.repository

org.eclipse.equinox.p2.repository.IMetadataRepositoryorg.eclipse.equinox.p2.repository.IArtifactRepository

o.e.e.p2.repository.IMetadataRepositoryManagero.e.e.p2.repository.IArtifactRepositoryManager


Provisioning agentHow do I get a repository manager or p2 components?

• The agent groups related services together– It is the starting point of everything.– It is the executable version of the p2 area (e.g the p2 folder in the

eclipse install)

– Several agents can run at once in one VM. Groups the services together. Allows to change some services (see implementations of IAgentServiceFactory)

– If you are only dealing with the running instance:• Obtain the IProvisioningAgent service from the OSGi registry• Create it using the IProvisioningContext#createAgent(null)

org.eclipse.equinox.p2.core

org.eclipse.equinox.p2.core.IProvisioningAgent

org.eclipse.equinox.p2.core.IProvisioningAgentProvider


Profile / profile registryHow do I know what is installed?

• A profile is the complete description in terms of IUs of what is installed.

• The profile registry knows about all the profiles in a given p2 area

org.eclipse.equinox.p2.engine

org.eclipse.equinox.p2.engine.IProfile

org.eclipse.equinox.p2.engine

org.eclipse.equinox.p2.engine.IProfileRegistry


What is not API?

• Repository serialized format

• Layout of files on disk under the p2 folder


Summary

• 3 levels of API tailored for different needs

Simple things should be simple

Complex things should be possible

This API is for YOU! Tell us what you think.


Thank you

mailto:[email protected]

http://wiki.eclipse.org/Equinox/p2





p2 related talks

• p2 savior or Achilles heel (Tues 4pm)– http://www.eclipsecon.org/2011/sessions?id=2313

• Raising p2 to the cloud (Wed 1:30pm)– http://www.eclipsecon.org/2011/sessions?id=2102

• Updates in the micro space (Thr 2:30pm)– http://www.eclipsecon.org/2011/sessions?id=2196

• Fireside chat on p2 (Wed 8:30pm)– http://www.eclipsecon.org/2011/sessions?id=2473


http://www.eclipsecon.org/2011/sessions?id=2313



discovery the p2 api (updated to indigo)

Technology