如何在PowerShell脚本中查询指定JSON响应的节点列表

Got it, let's walk through how to check your node states using PowerShell with that JSON data you have. Here's a practical, reusable approach:

First, you need to convert your JSON response into a PowerShell object—this makes it trivial to access and filter the node list. If your JSON is stored as a string (or coming from an API/file), here's how to parse it:

# Replace this with your actual JSON input (could also load from a file via Get-Content)
$jsonInput = @"
{ "properties": { "basic": { "nodes_table": [ { "node": "node1.prod.local:80", "state": "active", "weight": 1 }, { "node": "node2.prod.local:80", "state": "disabled", "weight": 1 }, { "node": "node3.prod.local:80", "state": "disabled", "weight": 1 }, { "node": "node4.prod.local:80", "state": "disabled", "weight": 1 }, { "node": "node5.prod.local:80", "state": "active", "weight": 1 } ] } } }
"@

# Convert JSON to a structured PowerShell object
$nodeTable = ($jsonInput | ConvertFrom-Json).properties.basic.nodes_table

Next, make a simple function to query any node's state. This keeps your code clean and lets you reuse the logic easily:

function Get-TargetNodeState {
    param(
        [Parameter(Mandatory=$true, HelpMessage="The node to check (e.g., node1.prod.local:80)")]
        [string]$NodeName,
        [Parameter(Mandatory=$true, HelpMessage="The parsed node table from your JSON")]
        [array]$NodeList
    )

    # Find the matching node entry
    $matchingNode = $NodeList | Where-Object { $_.node -eq $NodeName }

    if ($matchingNode) {
        Write-Output "Node *$NodeName* is currently **$($matchingNode.state)**"
    } else {
        Write-Warning "⚠️ Node '$NodeName' was not found in the node list"
    }
}

Now you can call the function to check any node's status:

# Check an active node
Get-TargetNodeState -NodeName "node1.prod.local:80" -NodeList $nodeTable

# Check a disabled node
Get-TargetNodeState -NodeName "node2.prod.local:80" -NodeList $nodeTable

# Test a node that doesn't exist
Get-TargetNodeState -NodeName "node6.prod.local:80" -NodeList $nodeTable

Quick Notes: #

• The ConvertFrom-Json cmdlet turns your raw JSON into a PowerShell object, so you can drill down to the nodes_table property easily.
• The function filters the node list to find your target, then returns a clear message with the state (bolded for visibility) or a warning if the node isn't present.
• You can adapt this to pull JSON directly from an API by replacing the hardcoded $jsonInput with a Invoke-RestMethod call, if needed.

内容的提问来源于stack exchange，提问作者Shahboz