[博客迁移]探索Windows Azure 监控和自动伸缩系列2

luobo2ni

　　上一篇博文介绍了如何连接Windows Azure: http://www.cnblogs.com/teld/p/5113063.html
　　本篇我们继续上次的示例代码，获取虚拟机的监控定义和监控数据。
　　有人会问，Azure Portal上已经有了监控数据，通过代码获取有意思吗？我们计划基于性能计数器的监控数据来实现应用的自动伸缩，因此可以获取到监控指标定义和监控数据应该是第一步。
　　在Azure的管理Portal中我们可以看到虚拟机的监控数据，目前，提供的主要有以下监控指标：
　　CPU Percentage；Disk Read; Disk Write; Network in；NetWork Out。
　　Azure中监控的Nuget主要是这个：Microsoft Azure Management Libraries
　　核心的几个namespace有：

　　我们本篇用的是Metric这个命名空间，核心类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>
/// 监控客户端
/// </summary>
class MonitorClient
{
private SubscriptionCloudCredentials credentials;
public MonitorClient(SubscriptionCloudCredentials credentials)
{
this.credentials = credentials;
}
/// <summary>
/// 获取所有的监控指标
/// </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);34
MetricDefinitionCollection metricDefinitions = metricListResponse.MetricDefinitionCollection;           
// Display the metric definitions.
int count = 0;
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();
}
}
}
}
　　使用上一篇我们的Azure 凭据验证器，获取一个令牌凭据TokenCloudCredentials，然后构造一个MonitorClient，获取指定虚拟机的监控数据。



static void Main(string[] args)
{            
var credential = Authorizator.GetCredentials();
var client = new MonitorClient(credential);
client.GetMetricDefinitions();
Console.ReadLine();
}
　　第一块代码中：
　　var resourceId = ResourceIdBuilder.BuildVirtualMachineResourceId("cloudServiceName", "deploymentName");
　　这个地方通ResourceIDBuilder获取虚拟机的资源ID，对应的参数分别为：cloudServiceName和deploymentName，第一个是虚拟机使用的云服务名称，第二个是虚拟机名称即可。
　　Run...
　　出错了：
　　{"ForbiddenError: The server failed to authenticate the request. Verify that the certificate is valid and is associated with this subscription."}
　　一番Google后未果，咋整，再分析下错误信息：

　　可以看到，请求的Uri：
　　{https://management.core.windows.net/37*****-5107-*****-*******6/services/monitoring/metricdefinitions/query?&resourceId=%2Fhostedservices%2Fteldptapp%2Fdeployments%2Fteldptapp}
　　请求又跑到Azure Global那去了。
　　这个错误困扰了好久，还在StackOverflow上发了英文咨询贴，不知道洋人们如何回答了。在此多谢鞠强老大的指导，想办法将请求的Uri定位到中国区的Azure。
　　重新分析了代码，找到了Monitor的构造函数中，可以指定Uri，将中国区Azure的Uri指定一下：https://management.core.chinacloudapi.cn



MetricsClient metricsClient = new MetricsClient(credentials, new Uri("https://management.core.chinacloudapi.cn/"));
　　测试通过，ok。
　　获取到了监控指标定义，接下来我们获取监控数据：



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>
/// 监控客户端
/// </summary>
class MonitorClient
{
private SubscriptionCloudCredentials credentials;
public MonitorClient(SubscriptionCloudCredentials credentials)
{
this.credentials = credentials;
}
/// <summary>
/// 获取所有的监控指标数据
/// </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 = 0;
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(5);
DateTime startTime = DateTime.UtcNow.AddHours(-1);
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...
　　程序在metricsClient.MetricValues.List(resourceId, metricNames, metricNamespace, timeGrain, startTime, endTime);
　　出错了：
Additional information: <string xmlns="http://schemas.microsoft.com/2003/10/Serialization/">{"Code":"InvalidRequest","Message":"Could not retrieve metrics."}</string>
　　为啥不能获取监控指标呢？
　　这个错误，Google一番依旧未果，咨询了微软的技术工程师，给了如下指导，resouceID必须执行RoleName：



var resourceId = ResourceIdBuilder.BuildVirtualMachineResourceId("cloudService", "deploymentName", "roleName");
　　修改之后，问题解决。
　　至此，我们已经可以获取到监控指标和监控数据，下一步我们要获取自定义的性能计数器，基于自定义的性能计数器来实现自动伸缩。
　　周国庆
　　2016/3