Add --enable-os-disk-full-caching for create/nodepool add

[weiliu2dev]

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❌Azure CLI Extensions Breaking Change Test

❌aks-preview

rule	cmd_name	rule_message	suggest_message
❌ 1007 - ParaRemove	aks create	cmd aks create removed parameter control_plane_scaling_size	please add back parameter control_plane_scaling_size for cmd aks create
❌ 1010 - ParaPropUpdate	aks nodepool add	cmd aks nodepool add update parameter spot_max_price: updated property default from nan to nan	please change property default from nan to nan for parameter spot_max_price of cmd aks nodepool add
⚠️ 1006 - ParaAdd	aks create	cmd aks create added parameter enable_os_disk_full_caching
⚠️ 1006 - ParaAdd	aks nodepool add	cmd aks nodepool add added parameter enable_os_disk_full_caching

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Hi @weiliu2dev,
Please write the description of changes which can be perceived by customers into HISTORY.rst.
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[yonzhan]

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Hi @weiliu2dev

Release Suggestions

Module: aks-preview

• Update VERSION to 20.0.0b7 in src/aks-preview/setup.py

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• For more info about extension versioning, please refer to Extension version schema

[Copilot]

Pull request overview

Adds support for enabling “full-cache ephemeral OS disk” on AKS nodepools (create + nodepool add) in the aks-preview extension.

Changes:

• Adds --enable-os-disk-full-caching (preview) to az aks create and az aks nodepool add.
• Wires the new flag through the agentpool decorator context and agentpool profile construction.
• Adds unit tests and help/changelog documentation for the new flag.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/aks-preview/azext_aks_preview/tests/latest/test_agentpool_decorator.py	Adds unit tests for new context getter and decorator setup behavior.
src/aks-preview/azext_aks_preview/custom.py	Adds enable_os_disk_full_caching param to command function signatures (but also drops control_plane_scaling_size).
src/aks-preview/azext_aks_preview/agentpool_decorator.py	Implements getter + agentpool field setup and plugs it into profile construction.
src/aks-preview/azext_aks_preview/_params.py	Adds CLI arguments for the new flag (but removes control_plane_scaling_size argument).
src/aks-preview/azext_aks_preview/_help.py	Documents the new flag (but removes --control-plane-scaling-size help/examples).
src/aks-preview/HISTORY.rst	Adds changelog entry for new flag; still mentions --control-plane-scaling-size.

Comments suppressed due to low confidence (1)

src/aks-preview/azext_aks_preview/_params.py:1274

• The aks create argument definition for control_plane_scaling_size was removed here, but managed_cluster_decorator.py still reads raw_param['control_plane_scaling_size'] and there are existing tests and HISTORY entries for this flag. This looks like an accidental regression that will make --control-plane-scaling-size/--cp-scaling-size unavailable. Please restore the c.argument(...) block (or, if intentionally removed, also clean up the decorator/tests/HISTORY accordingly).

        c.argument(
            "enable_gateway_api",
            action="store_true",
            help="Enable managed installation of Gateway API CRDs from the standard release channel."
        )
        c.argument(
            "enable_app_routing_istio",
            options_list=["--enable-app-routing-istio", "--enable-ari"],
            action="store_true",
            is_preview=True,
            help="Enable Gateway API based ingress on App Routing via Istio"
        )
        c.argument("enable_hosted_system", action="store_true", is_preview=True)
        c.argument(
            "enable_continuous_control_plane_and_addon_monitor",
            action="store_true",
            is_preview=True,
            help="Enable continuous control plane and addon monitor for the cluster.",
        )

[FumingZhang]

/azp run

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Azure Pipelines successfully started running 2 pipeline(s).

[FumingZhang]

highly recommend adding a scenario test to cover the change

[weiliu2dev]

highly recommend adding a scenario test to cover the change

Added in latest push (531dffb):

• test_aks_create_with_os_disk_full_caching and test_aks_nodepool_add_with_os_disk_full_caching
  in tests/latest/test_aks_commands.py
• Used @live_only() decorator following the enable_artifact_streaming pattern, since the feature
  is gated by Microsoft.ContainerService/FullCachePreview AFEC and an RP-side toggle
• Removed the missing_parameter_test_coverage linter exclusions — no longer needed