Simply scrapers to reduce duplicate code and make it easy to add… (#839)

* Reduce duplicate code in scraper

Signed-off-by: Tom Kerkhove <[email protected]>

* Use correct instance name and refactor resource definition

Signed-off-by: Tom Kerkhove <[email protected]>

src/Promitor.Core.Scraping/AppServiceScraper.cs

@@ -0,0 +1,63 @@
+using System.Collections.Generic;
+using Promitor.Core.Scraping.Configuration.Model.Metrics;
+
+// ReSharper disable All
+
+namespace Promitor.Core.Scraping
+{
+    /// <summary>
+    ///     Azure Monitor Scraper
+    /// </summary>
+    /// <typeparam name="TResourceDefinition">Type of metric definition that is being used</typeparam>
+    public abstract class AppServiceScraper<TResourceDefinition> : AzureMonitorScraper<TResourceDefinition>
+      where TResourceDefinition : class, IAppServiceResourceDefinition
+    {
+        /// <summary>
+        ///     Constructor
+        /// </summary>
+        protected AppServiceScraper(ScraperConfiguration scraperConfiguration) :
+            base(scraperConfiguration)
+        {
+        }
+
+        /// <summary>
+        /// Builds the URI without deployment slots of the App Service resource to scrape
+        /// </summary>
+        /// <param name="subscriptionId">Subscription id in which the resource lives</param>
+        /// <param name="scrapeDefinition">Contains all the information needed to scrape the resource.</param>
+        /// <param name="resource">Contains the resource cast to the specific resource type.</param>
+        /// <returns>Uri of Azure resource</returns>
+        protected abstract string BuildResourceUriWithoutDeploymentSlot(string subscriptionId, ScrapeDefinition<IAzureResourceDefinition> scrapeDefinition, TResourceDefinition resource);
+
+        /// <inheritdoc />
+        protected override string BuildResourceUri(string subscriptionId, ScrapeDefinition<IAzureResourceDefinition> scrapeDefinition, TResourceDefinition resource)
+        {
+            var slotName = DetermineSlotName(resource);
+            var resourceUri = BuildResourceUriWithoutDeploymentSlot(subscriptionId, scrapeDefinition, resource);
+
+            // Production slot should not be suffixed in resource URI
+            if (slotName != "production")
+            {
+                resourceUri += $"/slots/{slotName}";
+            }
+
+            return resourceUri;
+        }
+
+        /// <inheritdoc />
+        protected override Dictionary<string, string> DetermineMetricLabels(TResourceDefinition resourceDefinition)
+        {
+            var metricLabels = base.DetermineMetricLabels(resourceDefinition);
+
+            var slotName = DetermineSlotName(resourceDefinition);
+            metricLabels?.TryAdd("slot_name", slotName);
+
+            return metricLabels;
+        }
+
+        private static string DetermineSlotName(TResourceDefinition resource)
+        {
+            return string.IsNullOrWhiteSpace(resource.SlotName) ? "production" : resource.SlotName;
+        }
+    }
+}

src/Promitor.Core.Scraping/AzureMonitorScraper.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.Azure.Management.Monitor.Fluent.Models;
+using Promitor.Core.Scraping.Configuration.Model.Metrics;
+
+namespace Promitor.Core.Scraping
+{
+    /// <summary>
+    ///     Azure Monitor Scraper
+    /// </summary>
+    /// <typeparam name="TResourceDefinition">Type of metric definition that is being used</typeparam>
+    public abstract class AzureMonitorScraper<TResourceDefinition> : Scraper<TResourceDefinition>
+        where TResourceDefinition : class, IAzureResourceDefinition
+    {
+        /// <summary>
+        ///     Constructor
+        /// </summary>
+        protected AzureMonitorScraper(ScraperConfiguration scraperConfiguration) :
+            base(scraperConfiguration)
+        {
+        }
+
+        /// <inheritdoc />
+        protected override async Task<ScrapeResult> ScrapeResourceAsync(string subscriptionId, ScrapeDefinition<IAzureResourceDefinition> scrapeDefinition, TResourceDefinition resourceDefinition, AggregationType aggregationType, TimeSpan aggregationInterval)
+        {
+            var resourceUri = BuildResourceUri(AzureMetadata.SubscriptionId, scrapeDefinition, resourceDefinition);
+
+            var metricFilter = DetermineMetricFilter(resourceDefinition);
+            var metricName = scrapeDefinition.AzureMetricConfiguration.MetricName;
+            var dimensionName = scrapeDefinition.AzureMetricConfiguration.Dimension?.Name;
+            var foundMetricValue = await AzureMonitorClient.QueryMetricAsync(metricName, dimensionName, aggregationType, aggregationInterval, resourceUri, metricFilter);
+
+            var instanceName = resourceDefinition.GetResourceName();
+            var metricLabels = DetermineMetricLabels(resourceDefinition);
+
+            return new ScrapeResult(subscriptionId, scrapeDefinition.ResourceGroupName, instanceName, resourceUri, foundMetricValue, metricLabels);
+        }
+
+        /// <summary>
+        ///     Determines the metric filter to use
+        /// </summary>
+        /// <param name="resourceDefinition">Contains the resource cast to the specific resource type.</param>
+        protected virtual string DetermineMetricFilter(TResourceDefinition resourceDefinition)
+        {
+            return null;
+        }
+
+        /// <summary>
+        ///     Determines the metric labels to include in the reported metric
+        /// </summary>
+        /// <param name="resourceDefinition">Contains the resource cast to the specific resource type.</param>
+        protected virtual Dictionary<string, string> DetermineMetricLabels(TResourceDefinition resourceDefinition)
+        {
+            return new Dictionary<string, string>();
+        }
+    }
+}

src/Promitor.Core.Scraping/Configuration/Model/Metrics/AzureResourceDefinition.cs

@@ -1,11 +1,16 @@
 namespace Promitor.Core.Scraping.Configuration.Model.Metrics
 {
     /// <summary>
-    /// Describes a resource in Azure that can be scraped. Inheriting classes can add whatever
-    /// additional information is required to scrape a particular Azure resource.
+    ///     Describes a resource in Azure that can be scraped. Inheriting classes can add whatever
+    ///     additional information is required to scrape a particular Azure resource.
     /// </summary>
-    public abstract class AzureResourceDefinition
+    public abstract class AzureResourceDefinition : IAzureResourceDefinition
     {
+        /// <summary>
+        ///     Constructor
+        /// </summary>
+        /// <param name="resourceType">Type of resource that is configured</param>
+        /// <param name="resourceGroupName">Specify a resource group to scrape that defers from the default resource group.</param>
         protected AzureResourceDefinition(ResourceType resourceType, string resourceGroupName)
         {
             ResourceType = resourceType;
@@ -22,5 +27,8 @@ protected AzureResourceDefinition(ResourceType resourceType, string resourceGrou
         ///     This enables you to do multi-resource group scraping with one configuration file.
         /// </summary>
         public string ResourceGroupName { get; }
+
+        /// <inheritdoc />
+        public abstract string GetResourceName();
     }
-}
+}

src/Promitor.Core.Scraping/Configuration/Model/Metrics/IAppServiceResourceDefinition.cs

@@ -0,0 +1,7 @@
+namespace Promitor.Core.Scraping.Configuration.Model.Metrics
+{
+    public interface IAppServiceResourceDefinition : IAzureResourceDefinition
+    {
+        public string SlotName { get; }
+    }
+}

src/Promitor.Core.Scraping/Configuration/Model/Metrics/IAzureResourceDefinition.cs

@@ -0,0 +1,29 @@
+namespace Promitor.Core.Scraping.Configuration.Model.Metrics
+{
+    /// <summary>
+    ///     Describes a resource in Azure that can be scraped. Inheriting classes can add whatever
+    ///     additional information is required to scrape a particular Azure resource.
+    /// </summary>
+    public interface IAzureResourceDefinition
+    {
+        /// <summary>
+        ///     Type of resource that is configured
+        /// </summary>
+        public ResourceType ResourceType { get; }
+
+        /// <summary>
+        ///     Specify a resource group to scrape that defers from the default resource group.
+        ///     This enables you to do multi-resource group scraping with one configuration file.
+        /// </summary>
+        public string ResourceGroupName { get; }
+
+        /// <summary>
+        ///     Gets the name of the resource
+        /// </summary>
+        /// <remarks>This should return the name of the main resource</remarks>
+        /// <example>
+        ///     For an Azure SQL Database it should be the name of the DB, not the server
+        /// </example>
+        string GetResourceName();
+    }
+}

src/Promitor.Core.Scraping/Configuration/Model/Metrics/MetricDefinition.cs

@@ -12,7 +12,7 @@ public MetricDefinition(PrometheusMetricDefinition prometheusMetricDefinition,
             Scraping scraping,
             AzureMetricConfiguration azureMetricConfiguration,
             ResourceType resourceType,
-            List<AzureResourceDefinition> resources)
+            List<IAzureResourceDefinition> resources)
         {
             AzureMetricConfiguration = azureMetricConfiguration;
             PrometheusMetricDefinition = prometheusMetricDefinition;
@@ -44,17 +44,17 @@ public MetricDefinition(PrometheusMetricDefinition prometheusMetricDefinition,
         /// <summary>
         /// Gets or sets the list of resources to scrape.
         /// </summary>
-        public List<AzureResourceDefinition> Resources { get; set; }
+        public List<IAzureResourceDefinition> Resources { get; set; }
 
         /// <summary>
         /// Creates a <see cref="ScrapeDefinition{TResourceDefinition}"/> object for the specified resource.
         /// </summary>
         /// <param name="resource">The resource to scrape.</param>
         /// <param name="azureMetadata">The Azure global metadata.</param>
         /// <returns>The scrape definition.</returns>
-        public ScrapeDefinition<AzureResourceDefinition> CreateScrapeDefinition(AzureResourceDefinition resource, AzureMetadata azureMetadata)
+        public ScrapeDefinition<IAzureResourceDefinition> CreateScrapeDefinition(IAzureResourceDefinition resource, AzureMetadata azureMetadata)
         {
-            return new ScrapeDefinition<AzureResourceDefinition>(
+            return new ScrapeDefinition<IAzureResourceDefinition>(
                 AzureMetricConfiguration,
                 PrometheusMetricDefinition,
                 Scraping,

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/AppPlanResourceDefinition.cs

@@ -12,5 +12,8 @@ public AppPlanResourceDefinition(string resourceGroupName, string appPlanName)
         /// The name of the Azure App Plan to get metrics for.
         /// </summary>
         public string AppPlanName { get; set; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => AppPlanName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/ContainerInstanceResourceDefinition.cs

@@ -9,5 +9,8 @@ public ContainerInstanceResourceDefinition(string resourceGroupName, string cont
         }
 
         public string ContainerGroup { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => ContainerGroup;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/ContainerRegistryResourceDefinition.cs

@@ -9,5 +9,8 @@ public ContainerRegistryResourceDefinition(string resourceGroupName, string regi
         }
 
         public string RegistryName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => RegistryName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/CosmosDbResourceDefinition.cs

@@ -9,5 +9,8 @@ public CosmosDbResourceDefinition(string resourceGroupName, string dbName)
         }
 
         public string DbName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => DbName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/FunctionAppResourceDefinition.cs

@@ -1,6 +1,6 @@
 namespace Promitor.Core.Scraping.Configuration.Model.Metrics.ResourceTypes
 {
-    public class FunctionAppResourceDefinition : AzureResourceDefinition
+    public class FunctionAppResourceDefinition : AzureResourceDefinition, IAppServiceResourceDefinition
     {
         public FunctionAppResourceDefinition(string resourceGroupName, string functionAppName)
             : base(ResourceType.FunctionApp, resourceGroupName)
@@ -17,5 +17,8 @@ public FunctionAppResourceDefinition(string resourceGroupName, string functionAp
         /// The name of the deployment slot.
         /// </summary>
         public string SlotName { get; set; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => FunctionAppName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/GenericAzureResourceDefinition.cs

@@ -11,5 +11,8 @@ public GenericAzureResourceDefinition(string resourceGroupName, string filter, s
 
         public string Filter { get; }
         public string ResourceUri { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => null;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/NetworkInterfaceResourceDefinition.cs

@@ -9,5 +9,8 @@ public NetworkInterfaceResourceDefinition(string resourceGroupName, string netwo
         }
 
         public string NetworkInterfaceName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => NetworkInterfaceName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/PostgreSqlResourceDefinition.cs

@@ -9,5 +9,8 @@ public PostgreSqlResourceDefinition(string resourceGroupName, string serverName)
         }
 
         public string ServerName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => ServerName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/RedisCacheResourceDefinition.cs

@@ -9,5 +9,8 @@ public RedisCacheResourceDefinition(string resourceGroupName, string cacheName)
         }
 
         public string CacheName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => CacheName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/ServiceBusQueueResourceDefinition.cs

@@ -11,5 +11,8 @@ public ServiceBusQueueResourceDefinition(string resourceGroupName, string ns, st
 
         public string Namespace { get; }
         public string QueueName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => QueueName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/SqlDatabaseResourceDefinition.cs

@@ -27,5 +27,8 @@ public SqlDatabaseResourceDefinition(string resourceGroupName, string serverName
         /// The name of the database.
         /// </summary>
         public string DatabaseName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => DatabaseName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/SqlManagedInstanceResourceDefinition.cs

@@ -20,5 +20,8 @@ public SqlManagedInstanceResourceDefinition(string resourceGroupName, string ins
         /// The name of the Azure SQL Managed Instance resource.
         /// </summary>
         public string InstanceName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => InstanceName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/StorageQueueResourceDefinition.cs

@@ -13,5 +13,8 @@ public StorageQueueResourceDefinition(string resourceGroupName, string accountNa
         public string AccountName { get; }
         public string QueueName { get; }
         public Secret SasToken { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => AccountName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/VirtualMachineResourceDefinition.cs

@@ -9,5 +9,8 @@ public VirtualMachineResourceDefinition(string resourceGroupName, string virtual
         }
 
         public string VirtualMachineName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => VirtualMachineName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/VirtualMachineScaleSetsResourceDefinition.cs

@@ -9,5 +9,8 @@ public VirtualMachineScaleSetResourceDefinition(string resourceGroupName, string
         }
 
         public string ScaleSetName { get; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => ScaleSetName;
     }
 }

src/Promitor.Core.Scraping/Configuration/Model/Metrics/ResourceTypes/WebAppResourceDefinition.cs

@@ -1,6 +1,6 @@
 namespace Promitor.Core.Scraping.Configuration.Model.Metrics.ResourceTypes
 {
-    public class WebAppResourceDefinition : AzureResourceDefinition
+    public class WebAppResourceDefinition : AzureResourceDefinition, IAppServiceResourceDefinition
     {
         public WebAppResourceDefinition(string resourceGroupName, string webAppName, string slotName)
             : base(ResourceType.WebApp, resourceGroupName)
@@ -18,5 +18,8 @@ public WebAppResourceDefinition(string resourceGroupName, string webAppName, str
         /// The name of the deployment slot.
         /// </summary>
         public string SlotName { get; set; }
+
+        /// <inheritdoc />
+        public override string GetResourceName() => WebAppName;
     }
 }