上一篇博文介紹瞭如何連線Windows Azure: http://www.cnblogs.com/teld/p/5113063.html
本篇我們繼續上次的示例程式碼，獲取虛擬機器的監控定義和監控資料。
有人會問，Azure Portal上已經有了監控資料，通過程式碼獲取有意思嗎？我們計劃基於效能計數器的監控資料來實現應用的自動伸縮，因此可以獲取到監控指標定義和監控資料應該是第一步。
在Azure的管理Portal中我們可以看到虛擬機器的監控資料，目前，提供的主要有以下監控指標：
CPU Percentage；Disk Read; Disk Write; Network in；NetWork Out。
Azure中監控的Nuget主要是這個：Microsoft Azure Management Libraries
核心的幾個namespace有：
我們本篇用的是Metric這個名稱空間，核心類MetricClient：
namespace AzureTest
{
using Microsoft.WindowsAzure;
using Microsoft.WindowsAzure.Management.Monitoring.Metrics;
using Microsoft.WindowsAzure.Management.Monitoring.Metrics.Models;
using Microsoft.WindowsAzure.Management.Monitoring.Utilities; /// <summary>
/// 監控客戶端
/// </summary>
class MonitorClient
{
private SubscriptionCloudCredentials credentials; public MonitorClient(SubscriptionCloudCredentials credentials)
{
this.credentials = credentials;
} /// <summary>
/// 獲取所有的監控指標
/// </summary>
public void GetMetricDefinitions()
{
var metricsClient = new MetricsClient(credentials);
// Build the resource ID string.
var resourceId = ResourceIdBuilder.BuildVirtualMachineResourceId("cloudServiceName", "deploymentName");
Console.WriteLine("Resource Id: {0}", resourceId); //Get the metric definitions.
var metricListResponse=
metricsClient.MetricDefinitions.List(resourceId, null, null);
MetricDefinitionCollection metricDefinitions = metricListResponse.MetricDefinitionCollection;
// Display the metric definitions.
int count = ;
foreach (MetricDefinition metricDefinition in metricDefinitions.Value)
{
Console.WriteLine("MetricDefinitio: " + count++);
Console.WriteLine("Display Name: " + metricDefinition.DisplayName);
Console.WriteLine("Metric Name: " + metricDefinition.Name);
Console.WriteLine("Metric Namespace: " + metricDefinition.Namespace);
Console.WriteLine("Is Altertable: " + metricDefinition.IsAlertable);
Console.WriteLine("Min. Altertable Time Window: " + metricDefinition.MinimumAlertableTimeWindow);
Console.WriteLine();
}
}
}
}
使用上一篇我們的Azure 憑據驗證器，獲取一個令牌憑據TokenCloudCredentials，然後構造一個MonitorClient，獲取指定虛擬機器的監控資料。
static void Main(string[] args)
{
var credential = Authorizator.GetCredentials();
var client = new MonitorClient(credential);
client.GetMetricDefinitions();
Console.ReadLine();
}
第一塊程式碼中：
var resourceId = ResourceIdBuilder.BuildVirtualMachineResourceId("cloudServiceName", "deploymentName");
這個地方通ResourceIDBuilder獲取虛擬機器的資源ID，對應的引數分別為：cloudServiceName和deploymentName，第一個是虛擬機器使用的雲服務名稱，第二個是虛擬機器名稱即可。
Run...
出錯了：
{"ForbiddenError: The server failed to authenticate the request. Verify that the certificate is valid and is associated with this subscription."}
一番Google後未果，咋整，再分析下錯誤資訊：
可以看到，請求的Uri：
{https://management.core.windows.net/37*****-5107-*****-*******6/services/monitoring/metricdefinitions/query?&resourceId=%2Fhostedservices%2Fteldptapp%2Fdeployments%2Fteldptapp}
請求又跑到Azure Global那去了。
這個錯誤困擾了好久，還在StackOverflow上發了英文諮詢貼，不知道洋人們如何回答了。在此多謝鞠強老大的指導，想辦法將請求的Uri定位到中國區的Azure。
重新分析了程式碼，找到了Monitor的建構函式中，可以指定Uri，將中國區Azure的Uri指定一下：https://management.core.chinacloudapi.cn
MetricsClient metricsClient = new MetricsClient(credentials, new Uri("https://management.core.chinacloudapi.cn/"));
測試通過，ok。
獲取到了監控指標定義，接下來我們獲取監控資料：
namespace AzureTest
{
using Microsoft.WindowsAzure;
using Microsoft.WindowsAzure.Management.Monitoring.Metrics;
using Microsoft.WindowsAzure.Management.Monitoring.Metrics.Models;
using Microsoft.WindowsAzure.Management.Monitoring.Utilities;
/// <summary>
/// 監控客戶端
/// </summary>
class MonitorClient
{
private SubscriptionCloudCredentials credentials; public MonitorClient(SubscriptionCloudCredentials credentials)
{
this.credentials = credentials;
} /// <summary>
/// 獲取所有的監控指標資料
/// </summary>
public void GetMetricData()
{
var metricsClient = new MetricsClient(credentials, new Uri("https://management.core.chinacloudapi.cn/")); // Build the resource ID string.
var resourceId = ResourceIdBuilder.BuildVirtualMachineResourceId("cloudServiceName", "deploymentName");
Console.WriteLine("Resource Id: {0}", resourceId); //Get the metric definitions.
var metricListResponse = metricsClient.MetricDefinitions.List(resourceId, null, null);
MetricDefinitionCollection metricDefinitions = metricListResponse.MetricDefinitionCollection; var metricNamespace = "";
var metricNames = new List<string>();
// Display the metric definitions.
int count = ;
foreach (MetricDefinition metricDefinition in metricDefinitions.Value)
{
Console.WriteLine("MetricDefinitio: " + count++);
Console.WriteLine("Display Name: " + metricDefinition.DisplayName);
Console.WriteLine("Metric Name: " + metricDefinition.Name);
if (!metricNames.Contains(metricDefinition.Name))
metricNames.Add(metricDefinition.Name);
Console.WriteLine("Metric Namespace: " + metricDefinition.Namespace);
metricNamespace = metricDefinition.Namespace;
Console.WriteLine("Is Altertable: " + metricDefinition.IsAlertable);
Console.WriteLine("Min. Altertable Time Window: " + metricDefinition.MinimumAlertableTimeWindow);
Console.WriteLine();
} // timeGrain must be 5, 60 or 720 minutes.
TimeSpan timeGrain = TimeSpan.FromMinutes();
DateTime startTime = DateTime.UtcNow.AddHours(-);
DateTime endTime = DateTime.UtcNow; MetricValueListResponse response = metricsClient.MetricValues.List(resourceId, metricNames, metricNamespace, timeGrain, startTime, endTime); foreach (MetricValueSet value in response.MetricValueSetCollection.Value)
{
String valueName = value.Name;
Console.WriteLine("MetricValue:{0}", valueName);
foreach (MetricValue metricValue in value.MetricValues)
{
Console.WriteLine("Maximum:{0}{1}", metricValue.Maximum, value.Unit);
Console.WriteLine("Average:{0}{1}", metricValue.Average, value.Unit);
Console.WriteLine("Minimum:{0}{1}", metricValue.Minimum, value.Unit);
}
}
}
}
}
Run...
程式在metricsClient.MetricValues.List(resourceId, metricNames, metricNamespace, timeGrain, startTime, endTime);
出錯了：
Additional information: <string xmlns="http://schemas.microsoft.com/2003/10/Serialization/">{"Code":"InvalidRequest","Message":"Could not retrieve metrics."}</string>
為啥不能獲取監控指標呢？
這個錯誤，Google一番依舊未果，諮詢了微軟的技術工程師，給瞭如下指導，resouceID必須執行RoleName：
var resourceId = ResourceIdBuilder.BuildVirtualMachineResourceId("cloudService", "deploymentName", "roleName");
修改之後，問題解決。
至此，我們已經可以獲取到監控指標和監控資料，下一步我們要獲取自定義的效能計數器，基於自定義的效能計數器來實現自動伸縮。
周國慶