GAE: how to migrate appengine.api for Java8 to google cloud datastore for Java11

[Han Ju Kim]

Hi all,

I'm trying to keep up with my GAE standard webserver solution to latest one. Mainly Java8 to Java11. One of my package use the standard google appengine as described 

https://cloud.google.com/appengine/docs/standard/java/javadoc/com/google/appengine/api/datastore/DatastoreService

When I try to migrate my solution to Java11, my solution encountered many errors indicating some of Java file is not compatible with new Java11 binary as following

[INFO] -------------------------------------------------------------

[ERROR] COMPILATION ERROR : 

[INFO] -------------------------------------------------------------

[ERROR] /D:/workspace/FastGPS_Webapp_J11/vosao/api/src/main/java/org/vosao/global/SystemService.java:[31,34] cannot find symbol

  symbol:   class DatastoreService

  location: package com.google.cloud.datastore

[ERROR] /D:/workspace/FastGPS_Webapp_J11/vosao/api/src/main/java/org/vosao/global/SystemService.java:[66,9] cannot find symbol

  symbol:   class DatastoreService

  location: interface org.vosao.global.SystemService

[ERROR] /D:/workspace/FastGPS_Webapp_J11/vosao/api/src/main/java/org/vosao/entity/TemplateEntity.java:[28,34] cannot find symbol

  symbol:   class Text

  location: package com.google.cloud.datastore

[ERROR] /D:/workspace/FastGPS_Webapp_J11/vosao/api/src/main/java/org/vosao/entity/StructureEntity.java:[38,34] cannot find symbol

  symbol:   class Text

  location: package com.google.cloud.datastore

[ERROR] /D:/workspace/FastGPS_Webapp_J11/vosao/api/src/main/java/org/vosao/entity/FormConfigEntity.java:[26,34] cannot find symbol

  symbol:   class Text

  location: package com.google.cloud.datastore

[ERROR] /D:/workspace/FastGPS_Webapp_J11/vosao/api/src/main/java/org/vosao/utils/EntityUtil.java:[38,34] cannot find symbol

  symbol:   class Text

  location: package com.google.cloud.datastore

[INFO] 6 errors 

My solution is quite old and use appengine.api and objectify 5, but I would like to move to google cloud storage API and objectify 6. These are the classes generate compile errors or used in com.google.appengine.api.*, but removed latest google cloud datastore api. If there are any tip or workaround, it will be appreciated.

com.google.appengine.api.DatastoreServicecom.google.appengine.api.Textcom.google.appengine.api.PreparedQuerycom.google.appengine.api.FilterOperatorcom.google.appengine.api.SortDirectioncom.google.appengine.api.DatastoreServiceFactorycom.google.appengine.api.EntityNotFoundExceptioncom.google.appengine.api.FetchOptionscom.google.appengine.api.QueryResultListcom.google.appengine.api.AsyncDatastoreServicecom.google.appengine.api.CachingDatastoreServiceFactorycom.google.appengine.api.QueryResultIteratorcom.google.appengine.api.GeoPtcom.google.appengine.api.Entitiescom.google.appengine.api.CompositeFilterOperatorcom.google.appengine.api.Filtercom.google.appengine.api.FilterPredicatecom.google.appengine.api.DatastoreAttributescom.google.appengine.api.Indexcom.google.appengine.api.KeyRangecom.google.appengine.api.TransactionOptionscom.google.appengine.api.IndexState

com.google.appengine.api.CachingTransaction

Thanks in advanced,

[Elliott (Cloud Platform Support)]

Hello Han,

Please note that Google Groups are reserved for general Google Cloud Platform and product discussions and not for technical issues, which is why I suggest moving the troubleshooting to Stackoverflow, where you may receive advice from our programming community.

[Han Ju Kim]

Hi Elliott,

I appreciate your guide, however this is is not clearly described even stackoverflow [appengine] quite well. My solution run quite well in Java8, however I love to migrate that to latest on for Java11 and google cloud. It's a library provided from Google Cloud without any kind description on migration. When I deployed Java11, it generated lots of error like above. The google document for Java 11 and Datastore just say that it will be automatically migrated internally. However, nothing can be found anywhere.

There may be many developer experiencing same stuff. Is it too early to consider to migrate Java11? 

[Linus Larsen]

Hi

The gcloud sdk has different package names for the datastore classes, ex: com.google.cloud.datastore.Cursor.

I think you'll need to import the cloud datastore classes / client api. Check the bookshelf example app pom / parent pom.

[Han Ju Kim]

Hi Linus,

I appreciate kind advice. I also tried to look the example project. The issue is that my existing app engine built on datastore since 2011 and Google announce that datastore will automatically migrate to Firestore. So there are no user's requirement to do. When I try to deploy existing code after modifying compatible with Open JDK 11, it generate lots of error regarding datatore service and more. I can not find any material in google app engine document to resolve this. 

[Remko Tronçon]

I appreciate kind advice. I also tried to look the example project. The issue is that my existing app engine built on datastore since 2011 and Google announce that datastore will automatically migrate to Firestore. So there are no user's requirement to do. When I try to deploy existing code after modifying compatible with Open JDK 11, it generate lots of error regarding datatore service and more. I can not find any material in google app engine document to resolve this. 

AFAIK, Java 11 is a 2nd gen runtime, and the internal APIs are no longer available on these runtimes.

See https://cloud.google.com/appengine/docs/standard/java11/java-differences 

Remko