refactor: extract Defaults

Author: phnx47

src/Defaults.cs

@@ -0,0 +1,7 @@
+namespace Prometheus.Client.MetricServer;
+
+internal static class Defaults
+{
+    internal const string MapPath = "/metrics";
+    internal const string ContentType = "text/plain; version=0.0.4";
+}

src/MetricServer.cs

@@ -106,10 +106,9 @@ public IServiceProvider ConfigureServices(IServiceCollection services)
 
         public void Configure(IApplicationBuilder app)
         {
-            var contentType = "text/plain; version=0.0.4";
-
-            if (_options.ResponseEncoding != null)
-                contentType += $"; charset={_options.ResponseEncoding.BodyName}";
+            var contentType = _options.ResponseEncoding != null
+                ? $"{Defaults.ContentType}; charset={_options.ResponseEncoding.BodyName}"
+                : Defaults.ContentType;
 
             app.Map(_options.MapPath, coreapp =>
             {

src/MetricServerOptions.cs

@@ -23,7 +23,7 @@ public class MetricServerOptions
     /// <summary>
     ///     Endpoint path
     /// </summary>
-    public string MapPath { get; set; } = "/metrics";
+    public string MapPath { get; set; } = Defaults.MapPath;
 
     /// <summary>
     ///     Https certificate

src/Prometheus.Client.MetricServer.csproj

@@ -10,4 +10,7 @@
     <FrameworkReference Include="Microsoft.AspNetCore.App" />
     <PackageReference Include="Prometheus.Client" Version="[5.2.0,6.0.0)" />
   </ItemGroup>
+  <ItemGroup>
+    <InternalsVisibleTo Include="$(MSBuildProjectName).Tests, PublicKey=002400000480000094000000060200000024000052534131000400000100010035b85a8ca7e3391c4ac9123c6e51491977a1229b85e572e70350884579334c7d44e3c00de913f684eaab330ceeaba6eb41bbb359b7157ff17542a4e112856c4a18ab521eb7acb4f5a03f3d0a7e849e5406bae28d6780bb2453122e60b52aa76ae10611a1d4a0ffba682558c05ae2b5a0709c260b8a0c3afb15cf2ca0eed949ee" />
+  </ItemGroup>
 </Project>

tests/MetricServerTests.cs

@@ -40,7 +40,6 @@ public void Start_Stop_IsRunning()
         Assert.False(_metricServer.IsRunning);
     }
 
-
     [Fact]
     public void Start_DoubleStop_IsRunning()
     {
@@ -73,7 +72,6 @@ public void Start_Stop_WithDefaultPort_IsRunning()
         Assert.False(_metricServer.IsRunning);
     }
 
-
     [Fact]
     public void Start_Stop_WithDefaultRegisry_IsRunning()
     {
@@ -93,7 +91,7 @@ public async Task BaseMapPath_FindMetrics()
             var counter = Metrics.DefaultFactory.CreateCounter("test_counter", "help");
             counter.Inc();
             using var httpClient = new HttpClient();
-            string response = await httpClient.GetStringAsync($"http://localhost:{_port}/metrics");
+            string response = await httpClient.GetStringAsync($"http://localhost:{_port}{Defaults.MapPath}");
             Assert.False(string.IsNullOrEmpty(response));
             Assert.Contains("process_private_memory_bytes", response);
             Assert.Contains("dotnet_total_memory_bytes", response);
@@ -136,8 +134,8 @@ public async Task SetMapPath_FindMetricsWithEndSlash()
     }
 
     [Theory]
+    [InlineData(Defaults.MapPath)]
     [InlineData("metrics")]
-    [InlineData("/metrics")]
     [InlineData("metrics12")]
     [InlineData("/metrics965")]
     public async Task SetMapPath_FindMetrics(string mapPath)
@@ -181,7 +179,7 @@ public async Task CustomCounter_FindMetric()
             counter.Inc();
 
             using var httpClient = new HttpClient();
-            string response = await httpClient.GetStringAsync($"http://localhost:{_port}/metrics");
+            string response = await httpClient.GetStringAsync($"http://localhost:{_port}{Defaults.MapPath}");
             Assert.Contains(metricName, response);
         }
         catch (Exception ex)
@@ -202,7 +200,7 @@ public async Task AddLegacyMetrics_False_FindMetrics()
         {
             _metricServer.Start();
             using var httpClient = new HttpClient();
-            string response = await httpClient.GetStringAsync($"http://localhost:{_port}/metrics");
+            string response = await httpClient.GetStringAsync($"http://localhost:{_port}{Defaults.MapPath}");
             Assert.Contains("process_private_memory_bytes", response);
             Assert.Contains("dotnet_total_memory_bytes", response);
             Assert.DoesNotContain("process_private_bytes", response);
@@ -228,7 +226,7 @@ public async Task AddLegacyMetrics_True_FindMetrics()
         {
             _metricServer.Start();
             using var httpClient = new HttpClient();
-            string response = await httpClient.GetStringAsync($"http://localhost:{_port}/metrics");
+            string response = await httpClient.GetStringAsync($"http://localhost:{_port}{Defaults.MapPath}");
             Assert.Contains("process_private_memory_bytes", response);
             Assert.Contains("dotnet_total_memory_bytes", response);
             Assert.Contains("process_private_bytes", response);
@@ -285,7 +283,7 @@ public async Task CustormEncoding_FindHelp()
             counter.Inc();
 
             using var httpClient = new HttpClient();
-            string response = await httpClient.GetStringAsync($"http://localhost:{_port}/metrics");
+            string response = await httpClient.GetStringAsync($"http://localhost:{_port}{Defaults.MapPath}");
             Assert.Contains(help, response);
         }
         catch (Exception ex)