Docker buildkit support

When building a new container using the buildkit feature i.e..:

DOCKER_BUILDKIT=1 docker build .

The built image gets stuck in the _uploads folder in Artifactory.

The config layer of docker cannot be moved to the image folder since in it's content's history section, one of the members does not have the "created" key as follows:
"history": [
        

{             "created": "2019-08-20T20:19:55.062606894Z",             "created_by": "/bin/sh -c #(nop) ADD file:fe64057fbb83dccb960efabbf1cd8777920ef279a7fa8dbca0a8801c651bdf7c in / "         }

,
        

{             "created": "2019-08-20T20:19:55.211423266Z",             "created_by": "/bin/sh -c #(nop)  CMD [\"/bin/sh\"]",             "empty_layer": true         }

,
{
            "created_by": "CMD [\"sh\"]",
            "comment": "buildkit.dockerfile.v0",
            "empty_layer": true
        }
    ]
 
When pushing the image, the following error will be thrown in Artifactory:
 
2019-10-06 14:14:02,243 [http-nio-8081-exec-2] [INFO ] (o.j.r.d.v.r.h.DockerV2LocalRepoHandler:257) - Deploying docker manifest for repo 'buildkit' and tag 'yes' into repo 'docker-local'
2019-10-06 14:14:02,244 [http-nio-8081-exec-2] [DEBUG] (o.j.r.d.u.DockerUtils:134) - Searching manifest config blob in: 'buildkit/yes/sha256__fc587b796e67f3e4713fbe7752d27a7cf65958da3d80126a747919c8c49f01a5'
2019-10-06 14:14:02,245 [http-nio-8081-exec-2] [DEBUG] (o.j.r.d.u.DockerUtils:153) - Searching blob in 'buildkit/uploads/sha256_fc587b796e67f3e4713fbe7752d27a7cf65958da3d80126a747919c8c49f01a5'
2019-10-06 14:14:02,245 [http-nio-8081-exec-2] [DEBUG] (o.j.r.d.u.DockerUtils:155) - Blob found in: 'buildkit/uploads/sha256_fc587b796e67f3e4713fbe7752d27a7cf65958da3d80126a747919c8c49f01a5'
2019-10-06 14:14:02,252 [http-nio-8081-exec-2] [ERROR] (o.j.r.d.v.r.h.DockerV2LocalRepoHandler:783) - Error uploading manifest: 'null'
2019-10-06 14:14:02,252 [http-nio-8081-exec-2] [DEBUG] (o.j.r.d.v.r.h.DockerV2LocalRepoHandler:784) - Error uploading manifest:
java.lang.NullPointerException: null
at org.jfrog.repomd.docker.manifest.ManifestSchema2Deserializer.applyAttributesFromContent(ManifestSchema2Deserializer.java:95)
at org.jfrog.repomd.docker.manifest.ManifestSchema2Deserializer.deserialize(ManifestSchema2Deserializer.java:42)
at org.jfrog.repomd.docker.manifest.ManifestDeserializer.deserialize(ManifestDeserializer.java:32)
at org.jfrog.repomd.docker.v2.rest.handler.DockerV2LocalRepoHandler.processUploadedManifestType(DockerV2LocalRepoHandler.java:294)
at org.jfrog.repomd.docker.v2.rest.handler.DockerV2LocalRepoHandler.uploadManifest(DockerV2LocalRepoHandler.java:268)
at org.artifactory.addon.docker.rest.v2.repo.virtual.DockerV2VirtualRepoHandler.lambda$uploadManifest$5(DockerV2VirtualRepoHandler.java:110)
at org.artifactory.addon.docker.rest.v2.repo.virtual.DockerV2VirtualRepoHandler.delegateToLocalIfPossible(DockerV2VirtualRepoHandler.java:176)
at org.artifactory.addon.docker.rest.v2.repo.virtual.DockerV2VirtualRepoHandler.uploadManifest(DockerV2VirtualRepoHandler.java:110)
at org.jfrog.repomd.docker.v2.rest.DockerV2Resource.uploadManifest(DockerV2Resource.java:81)
at sun.reflect.GeneratedMethodAccessor504.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory.lambda$static$0(ResourceMethodInvocationHandlerFactory.java:76)
at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher$1.run(AbstractJavaResourceMethodDispatcher.java:148)
at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:191)
at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$ResponseOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:200)
at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:103)
at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:493)
at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:415)
at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:104)
at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:277)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:272)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:268)
at org.glassfish.jersey.internal.Errors.process(Errors.java:316)
at org.glassfish.jersey.internal.Errors.process(Errors.java:298)
at org.glassfish.jersey.internal.Errors.process(Errors.java:268)
at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:289)
at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:256)
at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:703)
at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:416)
at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:370)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:389)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:342)
at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:229)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.artifactory.webapp.servlet.RepoFilter.execute(RepoFilter.java:191)
at org.artifactory.webapp.servlet.RepoFilter.doFilter(RepoFilter.java:97)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.artifactory.webapp.servlet.AccessFilter.useAuthentication(AccessFilter.java:427)
at org.artifactory.webapp.servlet.AccessFilter.authenticateAndExecute(AccessFilter.java:305)
at org.artifactory.webapp.servlet.AccessFilter.doFilterInternal(AccessFilter.java:208)
at org.artifactory.webapp.servlet.AccessFilter.doFilter(AccessFilter.java:167)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.artifactory.webapp.servlet.RequestFilter.doFilter(RequestFilter.java:77)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.artifactory.webapp.servlet.ArtifactoryCsrfFilter.doFilter(ArtifactoryCsrfFilter.java:86)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.session.web.http.SessionRepositoryFilter.doFilterInternal(SessionRepositoryFilter.java:164)
at org.springframework.session.web.http.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:80)
at org.artifactory.webapp.servlet.SessionFilter.doFilter(SessionFilter.java:62)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.artifactory.webapp.servlet.ArtifactoryFilter.doFilter(ArtifactoryFilter.java:124)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493)
at org.apache.catalina.valves.rewrite.RewriteValve.invoke(RewriteValve.java:304)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:798)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:808)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1498)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:748)
 
When monitoring the push request using charles, it seems that the push for the v2 scheme fails and the client then pushed using v1 scheme and succeeds.
 
Steps to reproduce:
1) Build a docker image using the buildkit.
2) Push the image to Artifactory.