feat: add new Options, set default port

- CollectorRegistryInstance for set ICollectorRegistry
- UseDefaultCollectors for add default metrics

Author: phnx47

src/Prometheus.Client.MetricServer/MetricServer.cs

@@ -16,36 +16,54 @@ namespace Prometheus.Client.MetricServer
     public class MetricServer : IMetricServer
     {
         private readonly MetricServerOptions _options;
-        private readonly ICollectorRegistry _registry;
         private IWebHost _host;
 
         /// <summary>
         ///     Constructor
         /// </summary>
+        /// <param name="registry">Collector registry </param>
         /// <param name="options">Http server configuration options</param>
-        public MetricServer(MetricServerOptions options)
-            : this(null, options)
+        [Obsolete("Use options.CollectorRegistryInstance for set CollectorRegistry")]
+        public MetricServer(ICollectorRegistry registry, MetricServerOptions options)
         {
+            options.CollectorRegistryInstance = registry;
+
+            if (string.IsNullOrEmpty(options.MapPath) || !options.MapPath.StartsWith("/"))
+                throw new ArgumentException($"mapPath '{options.MapPath}' should start with '/'");
+
+            _options = options;
+
+            _options.CollectorRegistryInstance ??= Metrics.DefaultCollectorRegistry;
+
+            if (_options.UseDefaultCollectors)
+                _options.CollectorRegistryInstance.UseDefaultCollectors();
         }
 
         /// <summary>
         ///     Constructor
         /// </summary>
-        /// <param name="registry">Collector registry </param>
-        /// <param name="options">Http server configuration options</param>
-        public MetricServer(ICollectorRegistry registry, MetricServerOptions options)
+        public MetricServer()
+            : this(new MetricServerOptions())
+        {
+        }
+
+        /// <summary>
+        ///     Constructor
+        /// </summary>
+        public MetricServer(MetricServerOptions options)
         {
             if (options == null)
                 throw new ArgumentNullException(nameof(options));
 
-            if (options.Port == 0)
-                throw new ArgumentException("Port should be specified");
-
             if (string.IsNullOrEmpty(options.MapPath) || !options.MapPath.StartsWith("/"))
                 throw new ArgumentException($"mapPath '{options.MapPath}' should start with '/'");
 
-            _registry = registry ?? Metrics.DefaultCollectorRegistry;
             _options = options;
+
+            _options.CollectorRegistryInstance ??= Metrics.DefaultCollectorRegistry;
+
+            if (_options.UseDefaultCollectors)
+                _options.CollectorRegistryInstance.UseDefaultCollectors();
         }
 
         /// <inheritdoc />
@@ -69,7 +87,7 @@ public void Start()
                         options.Listen(IPAddress.Any, _options.Port, listenOptions => { listenOptions.UseHttps(_options.Certificate); });
                 })
                 .UseUrls($"http{(_options.Certificate != null ? "s" : "")}://{_options.Host}:{_options.Port}")
-                .ConfigureServices(services => { services.AddSingleton<IStartup>(new Startup(_registry, _options.MapPath)); })
+                .ConfigureServices(services => { services.AddSingleton<IStartup>(new Startup(_options.CollectorRegistryInstance, _options.MapPath)); })
                 .UseSetting(WebHostDefaults.ApplicationKey, typeof(Startup).GetTypeInfo().Assembly.FullName)
                 .Build();
 

src/Prometheus.Client.MetricServer/MetricServerOptions.cs

@@ -1,4 +1,5 @@
 using System.Security.Cryptography.X509Certificates;
+using Prometheus.Client.Collectors;
 
 namespace Prometheus.Client.MetricServer
 {
@@ -15,7 +16,7 @@ public class MetricServerOptions
         /// <summary>
         ///     Port number to listen
         /// </summary>
-        public int Port { get; set; }
+        public int Port { get; set; } = 5000;
 
         /// <summary>
         ///     Endpoint path
@@ -26,5 +27,15 @@ public class MetricServerOptions
         ///     Https certificate
         /// </summary>
         public X509Certificate2 Certificate { get; set; }
+
+        /// <summary>
+        ///     Collector Registry instance.
+        /// </summary>
+        public ICollectorRegistry CollectorRegistryInstance { get; set; }
+
+        /// <summary>
+        ///     Use default collectors
+        /// </summary>
+        public bool UseDefaultCollectors { get; set; } = false;
     }
 }

tests/Prometheus.Client.MetricServer.Tests/MetricServerTests.cs

@@ -19,7 +19,7 @@ public MetricServerTests(ITestOutputHelper testOutputHelper)
         }
 
         [Fact]
-        public void Start_Stop_IsRunning()
+        public void Start_Stop_LegacyConstructor_IsRunning()
         {
             var metricServer = new MetricServer(new CollectorRegistry(), new MetricServerOptions { Port = _port });
             metricServer.Start();
@@ -28,6 +28,16 @@ public void Start_Stop_IsRunning()
             Assert.False(metricServer.IsRunning);
         }
 
+        [Fact]
+        public void Start_Stop_DefaultPort_IsRunning()
+        {
+            var metricServer = new MetricServer();
+            metricServer.Start();
+            Assert.True(metricServer.IsRunning);
+            metricServer.Stop();
+            Assert.False(metricServer.IsRunning);
+        }
+
         [Fact]
         public async Task Base_MapPath()
         {
@@ -80,7 +90,6 @@ public async Task MapPath_WithEndSlash()
         public void Wrong_MapPath()
         {
             Assert.Throws<ArgumentException>(() => new MetricServer(
-                new CollectorRegistry(),
                 new MetricServerOptions { Port = _port, MapPath = "temp" }));
         }
 
@@ -112,11 +121,11 @@ public async Task MapPath(string mapPath)
         }
 
         [Fact]
-        public async Task FindMetric()
+        public async Task Find_Metric()
         {
             var registry = new CollectorRegistry();
             var factory = new MetricFactory(registry);
-            var metricServer = new MetricServer(registry, new MetricServerOptions { Port = _port });
+            var metricServer = new MetricServer(new MetricServerOptions { Port = _port, CollectorRegistryInstance = registry});
 
             try
             {
@@ -144,7 +153,7 @@ public async Task FindMetric()
         [Fact]
         public async Task Url_NotFound()
         {
-            var metricServer = new MetricServer(new CollectorRegistry(), new MetricServerOptions { Port = _port });
+            var metricServer = new MetricServer(new MetricServerOptions { Port = _port });
             try
             {
                 metricServer.Start();
@@ -165,5 +174,36 @@ public async Task Url_NotFound()
                 metricServer.Stop();
             }
         }
+
+        [Fact]
+        public async Task Find_Default_Metric()
+        {
+            var registry = new CollectorRegistry();
+            var metricServer = new MetricServer(new MetricServerOptions
+            {
+                Port = _port,
+                CollectorRegistryInstance = registry,
+                UseDefaultCollectors = true
+            });
+
+            try
+            {
+                metricServer.Start();
+
+                using var httpClient = new HttpClient();
+                string response = await httpClient.GetStringAsync($"http://localhost:{_port}/metrics");
+                Assert.Contains("dotnet_collection_count_total", response);
+                Assert.Contains("process_cpu_seconds_total", response);
+            }
+            catch (Exception ex)
+            {
+                _testOutputHelper.WriteLine(ex.ToString());
+                throw;
+            }
+            finally
+            {
+                metricServer.Stop();
+            }
+        }
     }
 }