Buckminster Aggregator User Guide
The Aggregator is based on and part of the Buckminster project. Buckminster provides a versatile and adaptable framework supporting build, assembly and deployment processes. It supports a rich set of usecases. One of those - the aggregation of repositories - is the focus of the Buckminster Aggregator tool.
The Aggregator combines p2 repositories from various sources into a new aggregated p2 repository. It can also be configured to produce an aggregated repository that can be used as a p2 and Maven repository. There appears to be an increasing need for delivering aggregated repositories. The reasons vary from licensing issues to organisational requirements:
- Owners of a p2 repo for a given project may not be in position to host all required or recommended components due to licensing issues - Buckminster's SVN support can serve as an example here, as it requires components available through the main Eclipse p2 repo as well as third-party components. Hence users have to visit several repos for a complete install.
- Projects want to provide convenient access to their products - Installation instructions requiring the user to visit several repos for a complete install are not uncommon. An aggregated repo for all those locations provides a convenient one-stop strategy. The aggregation may support mirroring all consumed p2 repos or simply providing an indirection via a composite repo.
- Organisations or teams want control over internally used components - It may be necessary to have gated access to relevant p2 repos and do an organisational "healthcheck" of those before internal distribution. Furthermore, internally used aggregated repos can provide a common basis for all organisational users.
The Aggregator tool is focused on supporting those specific requirements, rather than the complete set of usecases that Buckminster covers. Furthermore, it:
- is based on EMF models and as such is part of the transition of the Buckminster models to EMF-based models
- provides a simple user interface that does not delve into build specifics and should be accessible by a larger audience
- and the aggregation can be run headlessly once an aggregation definition has been created
Start by installing a fresh Eclipse 3.5 SDK from http://www.eclipse.org/downloads/ (The latest version used at the time of writing was http://download.eclipse.org/eclipse/downloads/drops/R-3.5.1-200909170800/index.php)
Aggregator with Buckminster
The Aggregator is not part of the official Galileo release. If you install the Aggregator from the repo mentioned above, into a workbench with Buckminster already installed, you may run into dependency conflicts. Instead update your Buckminster or install it from the following p2 repo: http://download.eclipse.org/tools/buckminster/updates-3.5
Getting started with standard examples
In the following we provide two simple examples that are easy to replicate and should highlight some of the features of the Aggregator. The first example deals with the creation of two variations of a p2 repo. The second shows the Aggregator's Maven support.
Aggregating a p2 repo
The first sample aggregation is build around Buckminster and its support for Subversive. The objective of this aggregated repo is to:
- provide a "one-stop shop" experience
- conveniently pull in third-party components that are not hosted at Eclipse
- provide this repo as an indirection mechanism if required
The example aggregation can be downloaded and opened in an appropriately set up workbench: Media:buckminster_galileo_m.build
Buckminster provides support for Subversive. Apart from the Subversive components at Eclipse (http://www.eclipse.org/subversive/), a complete installation will also require Subversive SVN connectors provided by Polarion (http://community.polarion.com/projects/subversive/download/eclipse/2.0/update-site/). We want to create a repo that combines all these components and makes them accessible from one location and for several pre-defined configurations.
This example already includes some of the more advanced aggregation features. Stepping through the model view from the top node the following components can be identified:
- The top node Aggregator groups all model definitions regarding Configurations and Contributions. Looking at the properties section at the bottom it is shown
- the top node has been provided with a mandatory Label with the value "Galileo + Buckminster for Subversive"; this will also be the label that would be used when accessing the aggregated repo via the p2 update manager
- the Build Root identifies the location to which the artifacts of the aggregated repo will be deployed
- The aggregation is defined for three configurations (i.e. os=win32,ws=win32,arch=x86; etc)
- any number of configurations can be defined
- during the aggregation process all dependencies of the contributed components will be verified for all provided configurations, unless exceptions are defined (see below)
- The first Contribution to the aggregation is labeled "Galileo 3.5".
- this contribution represents the simplest example of a contribution
- one Mapped Repository is defined for this contribution (it could be multiple); all that is needed is a user-defined label and the URL of the repository that should be included
- the result of this definition is that the complete Galileo p2 repo will be included in the aggregated repo
- The second Contribution is labeled "Subversive SVN connectors" and deals with the inclusion of bundles provided by Polarion. This contribution includes binary configuration-specific artifacts which are only available for win32. If a simple contribution would be defined the aggregation would fail for all non-win32 configurations, and hence the aggregation would fail as a whole.
- this requires a definition of Valid Configurations Rules that state exceptions
- the rules defined for the the three components in question essentially state that the verification process for those components should only be performed for win32-based configurations
- The third Contribution is labeled "Buckminster (latest)". It shows another advanced feature - an Exclusion Rule.
- the objective of the sample repo is to provide convenient setup of Buckminster with Subversive support. Since Buckminster's Subclipse and Subversive support are mutually exclusive, the features relevant for Subclipse can be excluded from the aggregated repo
- this is done using an Exclusion Rule defined for each Installable Unit that should be excluded
- At the bottom of the model editor view a list of all included repos is displayed.
- this list allows browsing the contents of all repos
- this part of the model is not editable
The aggregation can be run by right-clicking any node in the model and selecting Build Repository. This example was setup to use a mirroring approach for all contributed repos. Hence, the complete contents of all included can be found in the aggregated repos target location specified under Build Root.
INSERT OVERVIEW OF RESULTING STRUCTURE AND ARTIFACTS ... TBD !!!
Check the next section for a slightly different approach.
Providing a repo indirection
Mirroring all repo artifacts of your aggregated contributions may neither seem prudent nor necessary. This can be avoided by changing one property for the defined contributions.
Each Mapped Repository has property called Mirror Artifacts which can be set to
false in order to prevent copying all artifacts of the contributed repo to the aggregated repo.
The following Media:buckminster_galileo_i.build is a variation of the first example with the Mirror Artifacts property set to
false for all contributed repos. Running this aggregation will result in a composite repository that provides an indirection to the contributed repos.
INSERT OVERVIEW OF RESULTING STRUCTURE AND ARTIFACTS ... TBD !!!
Creating a Maven-conformant p2 repo
A powerful feature of the Aggregator is the ability to create aggregated repos that can be consumed as Maven repos, that is providing the structure and artifacts required by Maven. Those repos can in fact be consumed both as p2 and Maven repos. This flexibility is provided due to p2's separation of meta-data about dependencies and the actual location of the referenced artifacts.
In order to create a Maven-conformant aggregate repo all that is required is to set the property Maven Result property of the Aggregator to
true. The aggregation deployed to the Build Root location will be a Maven repo.
The sample Media:buckminster_galileo_maven.build is a variation of the previous aggregations configured to produce a Maven repo.
INSERT OVERVIEW OF RESULTING STRUCTURE AND ARTIFACTS ... TBD !!!
You will need a headless installation of Buckminster with the Aggregator feature installed.
Running from the command lineJust type:
buckminster aggregate <options>
For a detailed listing of the available options consult the next section.
Command line options
|--buildModel||<path to build model>||This value is required||Appoints the aggregation definition that drives the execution|
|BUILD|| Specifies the type of the execution.
|--buildId||<string>||build-<timestamp in the format yyyyMMddHHmm>||Assigns a build identifier to the aggregation. The identifier is used to identify the build in notification emails. Defaults to: build-<timestamp> where <timestamp> is formatted according as yyyyMMddHHmm, i.e. build-200911031527|
|--buildRoot||<path to directory>||buildRoot declared in the aggregation model||Controls the output. Defaults to the build root defined in the aggregation definition.|
|--production||N/A||N/A||Indicates that the build is running in real production. That means that no mock emails will be sent. Instead, the contacts listed for each contribution will get emails when things go wrong.|
|--emailFrom||<email>||Address of build master||Becomes the sender of the emails sent from the aggregator.|
|--mockEmailTo||<email>||?||Becomes the receiver of the mock-emails sent from the aggregator.|
|--mockEmailCC||<email>||?||Becomes the CC receiver of the mock-emails sent from the aggregator.|
|--logURL||<url>||N/A||The URL that will be pasted into the emails. Should normally point to the a public URL for output log for the aggregator so that the receiver can browse the log for details on failures.|
|--subjectPrefix||<string>||?||The prefix to use for the subject when sending emails. Defaults to the label defined in the aggregation definition. The subject is formatted as: "[<subjectPrefix>] Failed for build <buildId>"|
|--smtpHost||<host name>||localhost||The SMTP host to talk to when sending emails. Defaults to "localhost".|
|--smtpPort||<port number>||25||The SMTP port number to use when talking to the SMTP host. Default is 25.|
Aggregator model components and specific actions
This section provides an in-depth description and reference of the Aggregator model, listing all model components, properties and available actions.
When referring to ... TBD (conventions)
The following aggregator-specific actions are available via the context menu that can be invoked on any node in the Aggregator model editor:
- Clean Repository - cleans all traces of previous aggregations in the specified target location (Build Root)
- Verify Repository - verifies model validity and resolves dependencies; no artifacts are copied or created
- Build Repository - performs the aggregation and creates the aggregated repository in the target location (Build Root)
- Clean then Build Repository - performs a Clean followed by a Build
The root node of any aggregation model is the Aggregator node. It specifies a number of global properties including the Build Root (the target location of the aggregated repository) as well as the repo structure (maven-conformant or classic p2 setup). There are several child components some of which can be reference in other parts of the model: Configuration, Contribution, Contact, Custom Category, Validation Repository, Maven Mapping.
|Buildmaster||<Contact>?||-||Specifies an optional build master that will be notified of progress and problems if sending of mail is enabled. This is a reference to any Contact that has been added to this Aggregator model.|
|Build Root||<urn>||-||This is a required property specifying the target location of the aggregated repository.|
|Description||<string>||-||An optional description of the aggregated repository that would be visible if accessing the aggregated repository via the p2 update manager.|
|Label||<string>||-||A required label that will be used for the aggregated repository. This would be visible as the repo label if accessing the aggregated repository via the p2 update manager.|
|Maven Result|| true
|false|| Controls the output structure of the aggregated repo. If true, the aggregated repo will be Maven-conformant. Both the structure and meta-data of the aggregated repository will follow the conventions required by Maven.
NOTE that due to the flexibility of p2 (separation of meta-data about dependencies and location of artifacts) the aggregated repo will also function as a valid p2 repository.
|Packed Strategy|| Copy
Unpack as Sibling
|Copy|| This property controls how packed artifacts found in contributed repositories are handled when building the Aggregation:
|S|| Indicates the Aggregation type. This is an annotation merely for the benefit of the build master. It is not visible in the resulting repo.
An Aggregation may have one or more Configuration definitions. The aggregated repo will be verified for all added configurations. If dependencies for any of the given configurations fails the aggregation as a whole fails. It is however possible to specify exceptions for individual Contributions.
A Configuration is a combination of the following properties:
|-||Specifies the architecture for which this configuration should be verified.|
|-||Specifies the operating system for which this configuration should be verified.|
|-||Specifies the windowing system for which this configuration should be verified.|
Contributions are the key element of any aggregation. Contributions specify which repositories, or parts thereof (category, feature, product, IU), and according to which constraints they should be included in the aggregated repository. A contribution definition may consist of several Mapped Repository and Maven Mapping components.
|Contacts||<Contact>*||-||Zero or more references to Contacts defined in the given Aggregator model.|
|Description||<string>||-||Optional description of the contribution.|
|true||Disables (false) or enables (true) the contribution for the aggregation process. Note that this may lead to missing dependencies and hence verification errors.|
|Label||<string>||-||Mandatory label for this contribution.|
|Maven Mappings||<Maven Mapping>*||-||See Maven Mapping for details ...|
|Category Prefix||<string>||-||A prefix added to this repositories' label when displayed in the p2 update manager. In the absence of custom categories this allows a useful grouping of repositories in an aggregated repository.|
|Location||<URL>||This specifies the location of the repository that should be added to the enclosing Contribution and is a required property.|
|Metadata Repository||N/A||N/A||Specifies the type of repository. This property is inferred from the repository meta-data and is NOT editable.|
|Mirror Artifacts|| true
|true||Controls whether the contents (artifacts) of the specified repository will be copied to the target location of the aggregated repository.|
Validation Configuration Rule
The Aggregator supports the creation of Maven-conformant repositories. Those require a structure and naming conventions that may have to be achieved by a transformation of the Bundle-SymbolicName (BSN) when working with Eclipse bundles found at contributed repositories. Custom transformations are supported by the definition of one or more Maven Mappings which can be defined at the Aggregator and the Contribution level.