plat-16 using enterprise content in grails

Using Enterprise Content in Grails!

Robin Bramley, Ixxus!

Agenda!

•  Who I am!•  Setting the scene!•  Grails!•  CMIS!

•  Sample application styles!•  Document Management!•  Managed web content!

•  CMIS clients!•  Roll your own!•  OpenCMIS!

•  Practicalities!•  Alfresco extensions to CMIS!•  Performance!

•  Grails OpenCMIS Plugin!•  Alternatives!

My Background!

•  Senior Architect @ Ixxus!•  The UK Platinum partner!

•  Worked at consultancies for 13 years!•  Developing solutions with Alfresco since 0.6!•  First UK Alfresco Gold partner!

•  Around the edges I also write!•  GroovyMag author – inc. 4 hands-on Grails articles!•  DZone Most Valuable Blogger!

•  Re-published my series on Grails & Hudson / Jenkins!•  Open source contributions!

•  OpenID support for Acegi / Spring Security!•  Codenarc support for Hudson / Jenkins CI Violations plugin!

•  Presented at the London GGUG!

Grails!

•  Full-stack web framework!•  Embedded Tomcat & database!•  Allows for rapid development!

•  > grails create-application test •  > cd test •  > grails run-app

•  Scaffolding from domain classes!•  Convention over configuration!•  Builds on the shoulders of Giants!

•  Groovy!•  Spring Framework!•  Spring MVC!•  Hibernate!

•  Rich plugin ecosystem!•  Backed by SpringSource!

CMIS!

Content Management Interoperability Services standard!• Open standard published by OASIS!

•  Version 1.0 – 1st May 2010!•  Alfresco 3.3 was first CMIS 1.0 compliant product launched!

• ̒SQL for contentʼ!•  Query language!•  Virtual tables!

•  Folder!•  Document!•  Relationship!•  Policy!

• Bindings (ʻJDBC/ODBC equivalentʼ)!•  REST / AtomPub!•  SOAP Web Services!•  Browser binding in CMIS 1.1!

Documents & Folders!

Document •  Has a set of metadata

properties !•  Columns!•  Custom extensions!

•  May have a content stream (e.g. an actual file)!

•  May have renditions!

Folder •  Has a set of metadata

properties!•  Can have zero or more

children!•  Documents or Folders!

CMIS Repository Information !

Service Document •  3.x CMIS AtomPub binding: /alfresco/service/cmis •  4.x CMIS AtomPub binding: /alfresco/cmisatom

<cmisra:repositoryInfo> <cmis:repositoryId>ea9c2b9e-2892-4370-8791-4b0049f917f3</cmis:repositoryId> <cmis:repositoryName>Main Repository</cmis:repositoryName> <cmis:repositoryDescription>Main Repository</cmis:repositoryDescription> <cmis:vendorName>Alfresco</cmis:vendorName> <cmis:productName>Alfresco Repository (Community)</cmis:productName> <cmis:productVersion>4.0.0 (a 3755)</cmis:productVersion> <cmis:rootFolderId>workspace://SpacesStore/784b5b19-61ee-4963-a367-db6164ed43af</cmis:rootFolderId>

CMIS Query Syntax!SQL like •  Subset of SQL-92 with some extensions !

•  SELECT * FROM cmis:document •  SELECT * FROM cmis:folder

WHERE IN_FOLDER(‘folder-id’) •  SELECT * FROM cmis:document

WHERE IN_TREE(‘folder-id’) •  SELECT cmis:objectId, cmis:name, cmis:contentStreamLength

FROM cmis:DOCUMENT WHERE contains(‘fox’) OR cmis:name like ‘%fox%’

•  The complete BNF grammar is included in the specification at http://docs.oasis-open.org/cmis/CMIS/v1.0/os/cmis-spec-v1.0.html#_Toc243905422 !

CMIS Query Submission!•  Queries are submitted by POSTing application/cmisquery+xml

•  Accepted response format e.g. application/atom+xml;type=feed

<cmis:query xmlns:cmis=’http://docs.oasis-open.org/ns/cmis/core/200908/’>

<cmis:statement>SELECT * FROM cmis:document</cmis:statement>

<cmis:searchAllVersions>false</cmis:searchAllVersions>

<cmis:includeAllowableActions>false<cmis:includeAllowableActions>

<cmis:includeRelationships>none</cmis:includeRelationships>

<cmis:renditionFilter>*</cmis:renditionFilter>

<cmis:maxItems>-1</cmis:maxItems>

<cmis:pageSize>-1</cmis:pageSize>

<cmis:skipCount>0</cmis:skipCount>

</cmis:query>

Atom response!

Atom response – feed metadata!

<author><name>System</name></author> <generator version="4.0.0">Alfresco</generator> <icon>http://localhost:8080/alfresco/images/logo/AlfrescoLogo16.ico</icon> <id>urn:uuid:784b5b19-61ee-4963-a367-db6164ed43af-children</id> <title>Company Home Children</title> <updated>2011-11-01T18:54:14.541Z</updated> <opensearch:totalResults>5</opensearch:totalResults> <opensearch:startIndex>0</opensearch:startIndex> <opensearch:itemsPerPage>-1</opensearch:itemsPerPage> <cmisra:numItems>5</cmisra:numItems>

Atom response – entry!

<author><name>admin</name></author> <content src="http://localhost:8080/alfresco/service/cmis/s/workspace:SpacesStore/i/140c55fc-c8ca-4491-96ee-3c9d72214238/content"/><id>urn:uuid:140c55fc-c8ca-4491-96ee-3c9d72214238</id> <published>2011-11-01T18:54:14.529Z</published> <summary></summary> <title>Projects</title> <updated>2011-11-01T18:54:38.831Z</updated> <app:edited>2011-11-01T18:54:38.831Z</app:edited> <alf:icon>http://localhost:8080/alfresco/images/icons/space-icon-star-16.gif</alf:icon> <cmisra:object> <cmis:properties> <cmis:propertyId propertyDefinitionId="cmis:allowedChildObjectTypeIds" displayName="Allowed Child Object Types Ids" queryName="cmis:allowedChildObjectTypeIds"/> <cmis:propertyId propertyDefinitionId="cmis:objectTypeId" displayName="Object Type Id" queryName="cmis:objectTypeId"><cmis:value>cmis:folder</cmis:value></cmis:propertyId> <cmis:propertyString propertyDefinitionId="cmis:path" displayName="Path" queryName="cmis:path"><cmis:value>/Projects</cmis:value></cmis:propertyString> <cmis:propertyString propertyDefinitionId="cmis:name" displayName="Name" queryName="cmis:name"><cmis:value>Projects</cmis:value></cmis:propertyString> <cmis:propertyDateTime propertyDefinitionId="cmis:creationDate" displayName="Creation Date" queryName="cmis:creationDate"><cmis:value>2011-11-01T18:54:14.529Z</cmis:value></cmis:propertyDateTime> <cmis:propertyString propertyDefinitionId="cmis:lastModifiedBy" displayName="Last Modified By" queryName="cmis:lastModifiedBy"><cmis:value>admin</cmis:value></cmis:propertyString> <cmis:propertyString propertyDefinitionId="cmis:createdBy" displayName="Created by" queryName="cmis:createdBy"><cmis:value>admin</cmis:value></cmis:propertyString> <cmis:propertyId propertyDefinitionId="cmis:objectId" displayName="Object Id" queryName="cmis:objectId"><cmis:value>workspace://SpacesStore/140c55fc-c8ca-4491-96ee-3c9d72214238</cmis:value></cmis:propertyId> <cmis:propertyDateTime propertyDefinitionId="cmis:lastModificationDate" displayName="Last Modified Date" queryName="cmis:lastModificationDate"><cmis:value>2011-11-01T18:54:38.831Z</cmis:value></cmis:propertyDateTime> <cmis:propertyId propertyDefinitionId="cmis:parentId" displayName="Parent Id" queryName="cmis:parentId"><cmis:value>workspace://SpacesStore/784b5b19-61ee-4963-a367-db6164ed43af</cmis:value></cmis:propertyId> </cmis:properties> </cmisra:object> <cmisra:pathSegment>Projects</cmisra:pathSegment>

Links!Folder Tree Navigation

•  Can be achieved through queries!•  Specifying attributes means you can pull back less data!•  Can also apply criteria!

•  Atom entries also feature links including:!•  children (immediate)!

•  <link rel=”down” href=”http://cmis.alfresco. com:80/service/cmis/s/workspace:SpacesStore/ i/2dfb66de-9cb5-4e60-a786-5ea2ad8740d6/children” type=”application/atom+xml;type=feed”/> !

Links!Folder Tree Navigation

•  Atom entries links also including:!•  descendants (note type is cmistree)

•  <link rel=”down” href=”http://cmis.alfresco. com:80/service/cmis/s/workspace:SpacesStore/ i/2dfb66de-9cb5-4e60-a786-5ea2ad8740d6/descendants” type=”application/cmistree+xml”/> !

•  tree •  <link rel=”http://docs.oasis-open.org/ns/cmis/ link/200908/

foldertree” href=”http://cmis.alfresco. com:80/service/cmis/s/workspace:SpacesStore/ i/2dfb66de-9cb5-4e60-a786-5ea2ad8740d6/tree” type=”application/atom+xml;type=feed”/> !

•  Can apply depth control to these two!

Enough Theory?!

Application styles: Document Management!Simple repository client

•  First phase provided browse-search-retrieve!•  Intended for mobile usage (as featured in Alfresco 3 Business

Solutions by Martin Bergljung of Ixxus)!•  Uses an in-house roll your own Grails CMIS plugin!•  Authenticates users against Alfresco!

Application styles: Document Management!Simple repository client

Application styles: Web Content!

Blurb-style WCM •  Featured in!

•  Code requested by NASA !•  Taglib to embed identified

content!•  Backed by a service!

•  Uses OpenCMIS!•  Application level

credentials!

Application styles: Web Content!Associated documents

•  Web applications commonly have a need for associated documents!

•  E.g. case studies!•  This can be achieved by linking a

record to an Alfresco node reference!•  To zero to many documents!•  Or a folder!

•  An application built for one customer featured a folder picker for the admins!

•  Built as a taglib using AJAX with jQuery and jQuery UI components:!

•  dialog!•  treeview + treeview.async!

CMIS clients!

Roll your own •  Easy with

•  Commons HttpClient!•  XmlSlurper / GPath!•  MarkupBuilder!

•  Can add caching in Grails using Spring Modules Caching!

•  Flexible!•  Can easily get alf:icon etc.!

•  Arguably higher maintenance!

•  Minimal changes from 3.1.1/3.2 3.3/3.4 and then to 4.0!

OpenCMIS •  Java CMIS client and server

libraries!•  Part of!

•  Graduated from incubator in February!

•  Currently at version 0.5!•  Provides session-level

caching!•  Used by Alfresco!•  Doesnʼt support Alfresco

CMIS extensions*!

Practicalities: Alfresco CMIS extensions!

Aspects •  Alfresco uses the CMIS extension mechanism to allow for usage of

Aspects!•  E.g.!

<alf:aspects> <alf:appliedAspects>P:cm:titled</alf:appliedAspects>

<alf:properties>

<cmis:propertyString propertyDefinitionId="cm:description" displayName="Description" queryName="cm:description">

<cmis:value></cmis:value></cmis:propertyString> <cmis:propertyString propertyDefinitionId="cm:title" displayName="Title" queryName="cm:title">

<cmis:value></cmis:value></cmis:propertyString> </alf:properties>

</alf:aspects>

•  There is also an Alfresco OpenCMIS Extension!•  http://code.google.com/a/apache-extras.org/p/alfresco-opencmis-extension/ !•  Custom aspect-aware ObjectFactory implementation!•  0.2 POM depends on OpenCMIS Client Impl 0.3!

Practicalities: Performance!Tips

•  Filter!•  Donʼt ask for more data than you need!

•  Specify columns on queries (the wildcard is lazy)!•  Use the OperationContext filter!

•  Cache!•  Donʼt repeat yourself requests!

•  Use OpenCMIS session-level caching!•  Use Spring Modules application level caching if appropriate!•  Consider reverse proxy caches such as Varnish!

•  Compress!•  Donʼt waste bandwidth!

•  Compress the XML data types if the clients can handle it(see http://wiki.alfresco.com/wiki/CMIS#Compression) !

Time to crack open the code!

Grails OpenCMIS Plugin!•  What happened to it?!•  I jokingly blame Marc Palmer and his advice to plugin authors…!

•  Distilled guidance: “Make it work, make it simple, make it magic”!•  Though he didnʼt want people to not put a 0.1 out there!

•  But in reality the sponsoring project got delayed!•  So what magic is being considered for the road map?!•  Content-centric DSL !

•  Primarily around OpenCMIS API!•  GORM domain mapWith / mapping magic!

•  Could join the data mapping project as datastore-cmis!•  static mapWith = “cmis” •  Dynamic finders / criteria could use CMIS QL!•  But need to work out how feasible associative documents are!

•  E.g. only persist certain properties to CMISbyte[] document static mapping = { document mapWith:’cmis’ }

•  Plus taglibs, service, implementing the Alfresco extensions as a child plugin etc.!

Alternative Plugins!

Other possible solutions

•  Plugins that use the RivetLogic APIs!• http://www.grails.org/plugin/alfresco!

•  Last release 0.4 for Grails 1.1.1 in Feb 2010!•  Bundles old Alfresco core/repository jars and CMA 1.11!

• https://github.com/fix/grails-alfresco-plugin - uses Remote Access API rivet !

• RivetLogicʼs Crafter rivet for Grails!•  June 2010!

•  GORM JCR datastore!• Had dependencies on Jackrabbit!

Twitter: @rbramleyGitHub: https://github.com/rbramley

Blog: http://leanjavaengineering.com/ Web: http://www.ixxus.com !