Add package-2018-12-preview

[anusapan]

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[AutorestCI]

Automation for azure-sdk-for-python

The initial PR has been merged into your service PR:
Azure/azure-sdk-for-python#3206

[AutorestCI]

Automation for azure-sdk-for-js

The initial PR has been merged into your service PR:
Azure/azure-sdk-for-js#547

[AutorestCI]

Automation for azure-sdk-for-ruby

Nothing to generate for azure-sdk-for-ruby

[AutorestCI]

Automation for azure-sdk-for-go

Encountered a Subprocess error: (azure-sdk-for-go)

Command: ['/usr/local/bin/autorest', '/tmp/tmpsc86_whn/rest/specification/iothub/resource-manager/readme.md', '--go', '--go-sdk-folder=/tmp/tmpsc86_whn/src/github.com/Azure/azure-sdk-for-go', '--multiapi', '--preview-chk', '--use=@microsoft.azure/autorest.go@~2.1.127', '--use-onever', '--verbose']
Finished with return code 1
and output:

AutoRest code generation utility [version: 2.0.4283; node: v8.12.0]
(C) 2018 Microsoft Corporation.
https://aka.ms/autorest
   Loading AutoRest core      '/root/.autorest/@microsoft.azure_autorest-core@2.0.4289/node_modules/@microsoft.azure/autorest-core/dist' (2.0.4289)
   Including configuration file 'file:///tmp/tmpsc86_whn/rest/specification/iothub/resource-manager/readme.go.md'
   Loading AutoRest extension '@microsoft.azure/autorest.go' (~2.1.127->2.1.127)
   Loading AutoRest extension '@microsoft.azure/autorest.modeler' (2.3.38->2.3.38)
Processing batch task - {"tag":"package-2018-12-preview"} .
   Including configuration file 'file:///tmp/tmpsc86_whn/rest/specification/iothub/resource-manager/readme.go.md'
FATAL: System.InvalidOperationException: codegen for preview swagger Microsoft.Devices/preview/2018-12-01-preview/iothub.json must be under a preview subdirectory
   at AutoRest.Go.CodeGeneratorGo.<Generate>d__6.MoveNext() in /home/vsts/work/1/s/src/CodeGeneratorGo.cs:line 51
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at AutoRest.Go.Program.<ProcessInternal>d__3.MoveNext() in /home/vsts/work/1/s/src/Program.cs:line 107
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at NewPlugin.<Process>d__20.MoveNext() in /home/vsts/work/1/s/autorest.common/src/Plugins/NewPlugin.cs:line 163
FATAL: go/generate - FAILED
FATAL: Error: Plugin go reported failure.
Process() cancelled due to exception : Plugin go reported failure.
Failure during batch task - {"tag":"package-2018-12-preview"} -- Error: Plugin go reported failure..
  Error: Plugin go reported failure.

[AutorestCI]

Automation for azure-sdk-for-node

Nothing to generate for azure-sdk-for-node

[AutorestCI]

Automation for azure-sdk-for-java

Nothing to generate for azure-sdk-for-java

[azuresdkci]

Can one of the admins verify this patch?

[jianghaolu]

must have preview as suffix like this: https://github.com/Azure/azure-rest-api-specs/tree/master/specification/consumption/resource-manager#tag-package-2017-04-preview-and-java

[jianghaolu]

same for namespace. I would recommend having -preview on the tag as well.

[anusapan]

Fixed