We're targeting conceptual models with thousands of entity types. This is definitely beyond a single metadata document, and also beyond "read all metadata up-front".
So we will partition this conceptual model into hundreds of services, each with dozens of entity types, and dozens of references to "neighboring" services. Thus the need for lazy loading of referenced metadata documents. -----Original Message----- From: Francesco Chicchiriccò [mailto:[email protected]] Sent: Monday, 26. May 2014 16:28 To: [email protected] Subject: Re: 4.0: references in edm On 26/05/2014 14:00, Klevenz, Stephan wrote: > Hi Francesco, > > What do you think about to resolve references lazy? That would allow to > know top level resources without following the reference. Types are > qualified and and referenced documents can be resolved only if needed. Lazy resolution could be a nice enhancement but not straightforward to implement: EdmClientImpl would need to generate metadata requests "on-demand", e.g. only when accessing an element whose namespace wasn't fetched yet. > Otherwise documents could be very large in case of each reference is > resolved directly. Well, it's hard to me to figure out a "very large" document to include via reference, anyway... > I think an option not to follow references makes no sense. You are right > at the end the document will be incomplete. > > Regards, > Stephan > > On 26.05.14 12:44, "Francesco Chicchiriccò" <[email protected]> wrote: > >> On 26/05/2014 12:14, Klevenz, Stephan wrote: >>> Hi, >>> >>> I have implemented a first integration test [1] using the client code >>> to read service document and metadata from the server side >>> implementation. It works pretty cool except one issue. >>> >>> The metadata contains a reference uri and during deserialization this >>> link is requested and results in an exception due to incomplete proxy >>> settings. Well, I can correct my proxy settings of course but want also >>> to ask if there is a way to configure client not to follow links in >>> metadata? >> Hi Stephan, >> there is currently no such option, but it could be done by: >> >> 1. adding setFollowEdmReferences(boolean) / isFollowEmdReferences() to >> V4's Configuration [2] >> >> 2. checking Configuration#isFollowEdmReferences() before processing >> external references in XMLMetadataRequestImpl#execute [3] >> >> Anyway, I am actually not sure it would be correct: after all, an Edm >> document that declares external reference(s) is likely to have some >> unresolved elements in it, if client is not following the external >> references. >> >> WDYT? >> >> Regards. >> >>> <edmx:Edmx Version="4.0"> >>> <Reference >>> Uri="http://docs.oasis-open.org/odata/odata/v4.0/cs02/vocabularies/Org.OD >>> ata.Core.V1.xml"> >>> <Include Namespace="Org.OData.Core.V1" Alias="Core"/> >>> </Reference> >>> <edmx:DataServices> >>> >>> [1] >>> https://git-wip-us.apache.org/repos/asf?p=olingo-odata4.git;a=tree;f=fit/ >>> src/test/java/org/apache/olingo/fit/tecsvc;h=dadbedfacccbb63e0575c5112e91 >>> d21d41a6ae9e;hb=olingo-266-tecsvc >> [2] >> https://git-wip-us.apache.org/repos/asf?p=olingo-odata4.git;a=blob;f=lib/c >> lient-api/src/main/java/org/apache/olingo/client/api/v4/Configuration.java >> [3] >> https://git-wip-us.apache.org/repos/asf?p=olingo-odata4.git;a=blob;f=lib/c >> lient-core/src/main/java/org/apache/olingo/client/core/communication/reque >> st/retrieve/v4/XMLMetadataRequestImpl.java -- Francesco Chicchiriccò Tirasa - Open Source Excellence http://www.tirasa.net/ Involved at The Apache Software Foundation: member, Syncope PMC chair, Cocoon PMC, Olingo PMC http://people.apache.org/~ilgrosso/
