Azure Monitor - List available Diagnostic Log and Metric Categories for all Resource Types.ps1

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# PowerShell Snippet for calling Azure Provider REST API to list diagnostic categories for all supported resource types for all resource providers

# Authenticate to Azure - can automate with Azure AD Service Principal credentials

    Connect-AzAccount 

# Get list of all Azure resource providers

    $providerNames = 
        (Get-AzResourceProvider).ProviderNamespace

# Get token and create authorization header

    $azContext = Get-AzContext
    $azProfile = [Microsoft.Azure.Commands.Common.Authentication.Abstractions.AzureRmProfileProvider]::Instance.Profile
    $profileClient = New-Object -TypeName Microsoft.Azure.Commands.ResourceManager.Common.RMProfileClient -ArgumentList ($azProfile)
    $token = $profileClient.AcquireAccessToken($azContext.Subscription.TenantId)
    $authHeader = @{
        'Authorization'='Bearer ' + $token.AccessToken
    }

# Set other REST API parameters

    $action = "GET"
    $contentType = "application/json"
    $uriPrefix = "https://management.azure.com/providers/"
    $uriSuffix = "/operations?api-version="

# Enumerate diagnostic categories for supported resource types for all resource providers

    $providerNames | ForEach-Object {

        $providerName = $_

        $apiVersions = @()

        $apiVersions += 
           ((Get-AzResourceProvider -ProviderNamespace $providerName).ResourceTypes |
                Where-Object ResourceTypeName -eq "operations").ApiVersions

        $apiVersion = $apiVersions[0]

        if ($apiVersion -ne $null) {
                
           $uri = $uriPrefix + $providerName + $uriSuffix + $apiVersion

           $results = $null

           try {

                $results = 
                    Invoke-RestMethod `
                        -ContentType $contentType `
                        -Uri $uri `
                        -Method $action `
                        -Headers $authHeader 

            } catch [System.Net.WebException] { 

                if ( 
            
                    ($error[0].ErrorDetails.Message | ConvertFrom-Json).Error.Code `
                    -notin 
                    @("AuthorizationFailed","ResourceNotSupported") 

                ) 
                {
                
                    Write-Error $error[0].ErrorDetails.Message

                }

            }

            $results.value |
                Where-Object name -Like "*/logDefinitions/*" |
                Select-Object `
                    @{n='resourceType';e={%{ (($_.name.replace("/Microsoft.Insights",$null)).split("/") | ? {$_ -notIn @("providers", "logDefinitions", "read") }) -join "/" }}},
                    @{n='categoryType';e={"log"}},
                    @{n='categoryNames';e={$_.properties.serviceSpecification.logSpecifications.name}} 

            $results.value |
                Where-Object name -Like "*/metricDefinitions/*" |
                Select-Object `
                    @{n='resourceType';e={%{ (($_.name.replace("/Microsoft.Insights",$null)).split("/") | ? {$_ -notIn @("providers", "metricDefinitions", "read") }) -join "/" }}},
                    @{n='categoryType';e={"metric"}},
                    @{n='categoryNames';e={$_.properties.serviceSpecification.metricSpecifications.name}} 
        }

    } | 

    Where-Object categoryNames -ne $null |

    Sort-Object -Property categoryType, resourceType | 

    ConvertTo-Json