Difference between revisions of "Service Archive Specification"

Revision as of 15:34, 7 May 2008

Introduction

A 'Service' in DILIGENT is a software system that delivers functionalities, it is composed by a set of related 'Packages'.

In the DILIGENT context, a 'Package' is a 'piece of software' that can be deployed in a DHN. Packages are single files, compliant with the Package Model, that contain the files to be installed, along with rules describing software/packages dependencies, deployment instructions, etc.

Each service is described by a 'Profile' document, the 'Service Profile'.

For each Service Profile a corresponding 'Service Archive' should be delivered.

Structure

A Service Archive is a single TAR GZ file, which contains all the files declared on the Service Profile and has the following structure:

/-profile.xml
|
/-<PackageName>
|    |
|    |-<LibraryFile/GARArchive>
|    |-<additional files>
|
/-<PackageName>
|    |
|    |-<LibraryFile/GARArchive>
|    |-<additional files>
|
|-<PackageName>
|    |
|    |-<LibraryFile/GARArchive>
|    |-<additional files>
|
/.....

where:

• at the root level, the archive contains the Service Profile of the service itself. All the file names included in the archive have to be reported with a relative path starting from their <PackageName> folder (not included) *as defined on the Service Profile*.
• for every Package declared inside the Service Profile, the archive contains a directory (called with the same name of the PackageName field of the profile) including the corresponding jar/gar file:
  • for a WSRF service the name reported into the GARArchive field;
  • for a library/stubs the name reported into the LibraryFile field.

and any other additional file declared in the service profile (e.g. installation or reboot scripts)

Creating Service Archives

Manually

An easy way to create a Service Archive is to do it manually.

1. Create a folder structure as described in previous section according to the corresponding Service Profile.
2. Create a TAR GZ file of the created folder structure.

Using ETICS to automatically create Service Archives

Create a new component in ETICS for each service profile you already defined in order to create the related Service Archive as artefact. Let see now how you should do this in ETICS.

1. name the component as <ServiceName>.SERVICEARCHIVE
2. declare a static dependency against each ETICS component that produces a package to be included in the Service Archive. In this way, the packages forming the whole service are available and they are built immediately before they are packaged. Link this configuration with the corresponding root configuration, es. HEAD, 0_2_0.
3. use the CVS Commands to download additional files related to the whole service, but not included in the packages (like the Service Profile)
4. use the Build Commands available in ETICS in the following way:

INIT:
The init command has to be used to create the ${prefix} directory and all the <PackageName> subdirs

INSTALL:
The install command has to be used to move the GAR/JAR files and other additional files from their
 ${moduleDir}directory to the appropriate <PackageName> directory previously created.

PACKAGING:
Leave this command blank. At the end of the build process the default ETICS package command will create a
tar.gz (the ServiceArchive!) of the ${prefix} folder

To better understand the final result of the process above, you can have a look to the *.SERVICEARCHIVE components already created in ETICS.

Creating Software Archives

In some cases, it could be useful to define a group of packages not directly bound to a specific service. This is typically the case of:

• external software
• external libraries
• common libraries developed as part of the gCube framework not logically related to a single service

A Software Archive is a Service Archive file that includes only packages of the above types, without any WSRF service defined inside. Differently from the others, it is not possible to generate a Running Instance profile from this Archives at deployment time. They have the only role to group packages.

Prepare the packages

The way in which each package of the Service Archive has to be prepared depends on its type:

• if the package is a gCube library it has to be built and packaged as any other package following the ETICS guidelines
• if the package is an external software or library the appropriate tarball (.tar.gz) has to be prepared and made available on an HTTP location (typically on the ETICS repository). Then, an ETICS subsystem under the "ext" project that refers this tarball file has to be created. The Collective Layer behaves with these two kind of package as follows:

→ external library

all the JAR archives included in the tarball are copied in the $GLOBUS_LOCATION/lib folder and made available to the services hosted in that container

→ external software

the tarball is uncompressed and the install scripts inside are executed, while the reboot scripts and uninstall scripts scripts are scheduled; these scripts have to be declared in the package definition with their relative path inside the tarball.

Prepare the archive

In order to compile such kind of Service profile, the following steps have to be followed:

• declare the service class as SoftwareArchive
• define the list of one or more packages as described here (no WSRFService and/or Portlet package is accepted in the SoftwareArchive class)
• define on ETICS a subsystem (named with _SERVICEARCHIVE extension) that creates the related Service Archive tarball (.tar.gz) to upload on the Package Repository service as result of its build activities (see here)

Example

The following profile defines a Service Archive profile including an external software (eXist) available on a HTTP location:

<DILIGENTResource>
    <UniqueID>gfhwofi-423432-fdsff2-324432</UniqueID>
    <ResourceType>Service</ResourceType>
    <AuthorizationPolicies />
    <Profile>
        <Class>SoftwareArchive</Class>
        <Name>eXist</Name>
        <DescriptiveParameters>
            <DescParameter />
        </DescriptiveParameters>
        <QoS />
        <DLDependencies />
        <SpecificData />
        <PackagesList>
           <Package>
                <PackageName>eXist</PackageName>
                <PackageType>ExternalSoftware</PackageType>
                <Version>1.1</Version>
                <DLMandatory value="false" />
                <DHNMandatory value="false" />
                <VOMandatory value="false" />
                <DLSharable value="true" />
                <DisposeInterfaceSupport value="false" />
                <MultiVersionSupport value="false" />
                <VOSharingSupport value="false" />
                <ManifestFile />
                <InstallScripts>
                    <File>scripts/install1.1.sh</File>
                </InstallScripts>
                <UninstallScripts />
                <RebootScripts>
                    <File>scripts/reboot.sh</File>
                </RebootScripts>
                <Dependencies />
                <DHNRequirements>
                    <Req category="RunTimeEnv" operator="eq" requirement="Variable" value="java1.5" />
                    <Req category="OperatingSystem" operator="eq" requirement="Name" value="Linux" />
                </DHNRequirements>
                <ConfigurationFiles />
                <ExternalSoftware>
                    <DownloadFrom>http://grids17.eng.it/engrepository/exist/1.1.1/noarch/eXist-1.1.1-newcore-build4311.tar.gz</DownloadFrom>
                    <Description>eXist XML database</Description>
                </ExternalSoftware>
                <OtherFiles />
                <OtherProperties />
            </Package>
        </PackagesList>
    </Profile>
</DILIGENTResource>

The following tarball file has to be produced as artifact by the *_SERVICEARCHIVE ETICS subsystem defined for such a purpose:

/eXist
   |-ServiceProfile_eXist_SoftwareArchive.xml
   |
   /scripts
      |
      |- install1.1.sh
      |- reboot.sh

A dependency against any package declared in a SoftwareArchive class has to be specified as usual.

--Henri 17:40, 27 March 2007 (EEST)

--Updated by Manuele Simi 18:43, 20 July 2007 (EET)