Google Endpoints V2 and Maven plugin version? - google-app-engine

We have a multi-module (war-packaged) project that uses com.google.appengine - appengine-maven-plugin target being ear file.
We have migrated succesfully to Java8 and EndpointsV2. It builds and runs fine in Cloud. However the following requirement is still a bit questionmark in the migration instructions. What is the reason behind this incompatibility and requirement? Or is it just related to for example "discovery docs" that we are not using anyway?
The old App Engine Maven plugin, with group com.google.appengine, is incompatible with the Endpoints Framework plugin. You must use the new version shown above
https://cloud.google.com/endpoints/docs/frameworks/java/migrating

If you aren't using discovery docs or generated client libraries and are only using Endpoints as a library dependency, you can remove the Endpoints plugin and the error should go away.

Related

NoClassDefFoundError: Could not initialize OauthRawGcsServiceFactory on production environment

I'm using appengine-sdk 1.9.3.
In devserver, works in Eclipse and Ant normally.
When I deploy (update) to appengine (production environment), I get this error:
event.getResults(): [<pre>Error for /p7/formPanelServlet
java.lang.NoClassDefFoundError: Could not initialize class
com.google.appengine.tools.cloudstorage.oauth.OauthRawGcsServiceFactory
at com.google.appengine.tools.cloudstorage.GcsServiceFactory.createRawGcsService(GcsServiceFactory.java:42)
at com.google.appengine.tools.cloudstorage.GcsServiceFactory.createGcsService(GcsServiceFactory.java:34)
at com.bitvisio.p7.server.FormPanelServlet.<init>(FormPanelServlet.java:27)
At FormPanelServlet.java:27, the code is:
private final GcsService gcsService = GcsServiceFactory
.createGcsService(new RetryParams.Builder()
.initialRetryDelayMillis(10)
.retryMaxAttempts(10)
.totalRetryPeriodMillis(15000)
.build());
I put the lib appengine-gcs-client-0.3.9.jar in war/WEB-INF/lib. I think there is a problem with this lib.
Thanks for help.
Always use tools like Maven or Ivy to resolve dependencies for you. Copying JARs to war/WEB-INF/lib/ directory and editing .classpath file manually will be painful and may not help you always. If you use Eclipse & Google App Engine plugin, use Add Google APIs... as mentioned here - Google Plugin for Eclipse. In my case, adding Cloud Storage API via Google Plugin for Eclipse helped resolve this NoClassDefFoundError.
I had the same problem. I use Ivy to resolve dependencies and always get the latest.integration (with Maven use RELEASE) for revisions.
However I usually ignore transitive libraries. It looks like Google is expanding the API family - at least splitting out discrete functionality.
There are now quite a few transitive dependencies and it seems they released a new version of the GCS client around the same time as 1.9.3.
Getting all dependencies and packaging them in my deployment fixed my issue. I did not have the issue in development which made it more confusing.
You are facing this issue because you are not adding the some of the jar like
google-api-services-storage-v1-rev78-1.22.0.jar download link
joda-time-2.94.jar download link
guava-19.0.jar link to download
you can use the different version of jar according to your appengine-gcs-client jar file.
Note : Add all these jar and build path with the project and problem will get solve.

Can't import library into Google App Engine project

I use the Google App Engine SDK 1.8.5 with Eclipse 3.8 on Ubuntu.
I want to add the Cloud Storage service to my app, so I downloaded guava-gwt-15.0.jar and appengine-gcs-client-0.3.jar, and put them in my apps /war/WEB-INF/lib/ folder. I also added these jars to the build path in Eclipse.
When I fire up my app in dev mode, it runs fine, at least until I try to access a page relevant to the GCS library. When I do that, I get the following error:
java.lang.NoClassDefFoundError: com/google/common/base/Preconditions
at com.google.appengine.tools.cloudstorage.GcsServiceImpl.<init>(GcsServiceImpl.java:35)
at com.google.appengine.tools.cloudstorage.GcsServiceFactory.createGcsService(GcsServiceFactory.java:32)
... etc
I cleaned my project and restarted Eclipse multiple times, and still the problem persists. What to do?
In addition to Guava for GWT, you also need the core Guava library (guava-15.0.jar). Download the .jar to war/WEB-INF/lib and add it to you build path as well.

Selecting GWT module to compile for deployment to App Engine

I introduced additional GWT modules where previously there's only been one in my GWT/GAE project. When deploying to App Engine via Google Plugin for Eclipse I noticed that the plugin compiles all the GWT modules in the project, which is not what I want. I wasn't able to find a way to tell GPE which GWT modules to compile for deployment. Is this at all possible?
Apparently GPE compiles GWT modules in the module list found in Project Properties --> Google --> Web Toolkit so removing modules from there did the trick. I was expecting to find either a way to select GWT modules from the GAE Deployment Dialog or to edit some configuration file.
It has to be admitted that relying on such GPE settings is not a great way to make consistent deployments. Maven-based builds and deployments made outside of Eclipse are likely a better way to go.

Datanucleus using wrong enhancer in Google App Engine 1.7

I'm having difficulty in getting Datanucleus 2 to work properly with enhancing classes on GAE 1.7.0 in Eclipse using the Datanucleus plugin. This worked fine in older versions of GAE when I'd follow the manual steps here:
http://www.datanucleus.org/products/accessplatform/guides/eclipse/index.html
But since upgrading, GAE now includes these libs (newer versions of them it looks like), and also GAE has a new "enhancer" flag you can set. I can't find anyway to set this flag in Eclipse though. It appears that GAE is still including the v1 libs when I want the V2 libs and Datanucleus is having conflicts according to this error:
Jul 1, 2012 5:59:55 PM org.datanucleus.enhancer.DataNucleusEnhancer <init>
INFO: DataNucleus Enhancer : Using ClassEnhancer "ASM" for API "JPA"
Exception in thread "main" java.lang.NoSuchFieldError: NUCLEUS_CONTEXT_LOADER
at org.datanucleus.NucleusContext.<clinit>(NucleusContext.java:73)
at org.datanucleus.enhancer.DataNucleusEnhancer.<init>(DataNucleusEnhancer.java:171)
at org.datanucleus.enhancer.DataNucleusEnhancer.main(DataNucleusEnhancer.java:1265)
I've tried many different things. I've tried using all the defaults. I've tried adding the v2 libs to the Datanucleus runtime Classpath Entries. I've tried deleting the v1 libs in the GAE 1.7.0 SDK in both the src and libs. But somehow GAE is still pulling over (or trying to pull over the V1 libs. I've even tried the older method of manually setting up the configuration as specified by the link above. It's a little frustrating as it seems like I'm now in a situation where I can't use these libs at all. At least with older versions of GAE I could manually set it up to work. Nothing seems to work now. Any suggestions?
I hit this same error and was able to resolve it in my project by:
Doing what DavidB suggested in the comments, without modifying the DataNucleus JPA settings in the preferences.
Deleting all of the "V1" jars from the war/WEB-INF/lib
To clarify DavidB's suggestion, open the directory that holds your project. There will be a folder named ".settings", open this and edit com.google.appengine.eclipse.core.prefs. Just change the third line from gaeDatanucleusVersion=v1 to gaeDatanucleusVersion=v2
Once you have done this, remove the following jars from you war/WEB-INF/lib directory:
datanucleus-appengine-1.0.10.final.jar
datanucleus-core-1.1.5.jar
datanucleus-jpa-1.1.5.jar
geronimo-jpa_3.0_spec-1.1.1.jar
geronimo-jta_1.1_spec-1.1.1.jar
jdo2-api-2.3-eb.jar
Restart eclipse and you should be good to go.

Gradle 0.9.2 with Appengine 1.4.2

Is there a Gradle plugin (compatible with Gradle 0.9.2) that'll let me deploy to Google App Engine 1.4.2?
If yes, how can I integrate it (build.gradle snippet)?
Axel,
today is your lucky day. ;-) I just released a Gradle GAE plugin that provides tasks for uploading, running and managing Google App Engine Java projects. Give it a shot. The
documentation describes setup and convention properties in detail. Let me know if you have feedback or feature requests.
The Spring Security build uses gradle to deploy a sample app to GAE. You could copy that (see the sample app gradle file), or clone the repo and use it in place as a guide. It uses a simple internal plugin.

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