ako_config_diff

Instructions

Implementation Reference

• vmware_avi/ops/ako_config.py:28-48 (handler)

  Core handler: runs `helm diff upgrade ako avi/ako -n avi-system` to show pending Helm changes. Returns output via rich console which is captured by the MCP server.

  def diff_ako_config(namespace: str = "avi-system") -> None:
      """Show pending Helm changes via helm diff."""
      result = subprocess.run(
          ["helm", "diff", "upgrade", "ako", "avi/ako", "-n", namespace],
          capture_output=True,
          text=True,
          timeout=120,
      )
      if result.returncode != 0:
          console.print(
              "[yellow]helm-diff plugin may not be installed. "
              "Install: helm plugin install https://github.com/databus23/helm-diff[/yellow]"
          )
          console.print(f"[red]{result.stderr.strip()}[/red]")
          raise SystemExit(1)
  
      if not result.stdout.strip():
          console.print("[green]No pending changes.[/green]")
      else:
          console.print("\n[bold]Pending Changes[/bold]\n")
          console.print(result.stdout)

• mcp_server/server.py:333-341 (schema)

  MCP tool definition: decorated with @mcp.tool and @vmware_tool, annotated as read-only, low-risk. Calls diff_ako_config() and captures output.

  @mcp.tool(annotations={"readOnlyHint": True, "destructiveHint": False, "idempotentHint": True, "openWorldHint": True})
  @vmware_tool(risk_level="low")
  def ako_config_diff() -> str:
      """[READ] Show pending Helm value changes that haven't been applied yet.
  
      Use before ako_config_upgrade to review what will change.
      """
      from vmware_avi.ops.ako_config import diff_ako_config
      return _capture_output(diff_ako_config)

• mcp_server/server.py:333-341 (registration)

  Registration via @mcp.tool decorator with annotations and @vmware_tool. The function name 'ako_config_diff' becomes the tool name in MCP.

  @mcp.tool(annotations={"readOnlyHint": True, "destructiveHint": False, "idempotentHint": True, "openWorldHint": True})
  @vmware_tool(risk_level="low")
  def ako_config_diff() -> str:
      """[READ] Show pending Helm value changes that haven't been applied yet.
  
      Use before ako_config_upgrade to review what will change.
      """
      from vmware_avi.ops.ako_config import diff_ako_config
      return _capture_output(diff_ako_config)

• mcp_server/server.py:24-48 (helper)

  Helper function _capture_output() that runs a function and captures its Rich console output as plain text for MCP response.

  def _capture_output(func, *args, **kwargs) -> str:
      """Run a function and capture its Rich console output as plain text."""
      import importlib  # noqa: F401 — used via sys.modules lookup
      import sys
  
      buf = StringIO()
      from rich.console import Console
      capture_console = Console(file=buf, force_terminal=False, width=120)
  
      mod_name = func.__module__
      mod = sys.modules.get(mod_name)
      original_console = getattr(mod, "console", None) if mod else None
  
      if mod and original_console is not None:
          mod.console = capture_console
  
      try:
          func(*args, **kwargs)
      except SystemExit:
          pass
      finally:
          if mod and original_console is not None:
              mod.console = original_console
  
      return buf.getvalue()

• vmware_avi/cli.py:311-316 (registration)

  CLI command registration for 'ako config-diff' typer sub-command, also calling diff_ako_config().

  @ako_app.command("config-diff")
  def ako_config_diff_cmd() -> None:
      """Show pending Helm changes (diff)."""
      from vmware_avi.ops.ako_config import diff_ako_config
  
      diff_ako_config()