[Exporter.Prometheus] - enable analysis

.editorconfig

@@ -160,6 +160,9 @@ dotnet_diagnostic.RS0041.severity = suggestion
 # CA1515: Disable making types internal for Tests classes. It is required by xunit
 dotnet_diagnostic.CA1515.severity = none
 
+# CA2007: Disable Consider calling ConfigureAwait on the awaited task. It is not working with xunit
+dotnet_diagnostic.CA2007.severity = none
+
 [**/obj/**.cs]
 generated_code = true
 

src/OpenTelemetry.Exporter.Prometheus.AspNetCore/OpenTelemetry.Exporter.Prometheus.AspNetCore.csproj

@@ -7,6 +7,7 @@
     <PackageTags>$(PackageTags);prometheus;metrics</PackageTags>
     <MinVerTagPrefix>coreunstable-</MinVerTagPrefix>
     <DefineConstants>$(DefineConstants);PROMETHEUS_ASPNETCORE</DefineConstants>
+    <AnalysisLevel>latest-all</AnalysisLevel>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(RunningDotNetPack)' != 'true'">

src/OpenTelemetry.Exporter.Prometheus.AspNetCore/PrometheusExporterApplicationBuilderExtensions.cs

@@ -99,6 +99,8 @@ public static IApplicationBuilder UseOpenTelemetryPrometheusScrapingEndpoint(
         Action<IApplicationBuilder>? configureBranchedPipeline,
         string? optionsName)
     {
+        Guard.ThrowIfNull(app);
+
         // Note: Order is important here. MeterProvider is accessed before
         // GetOptions<PrometheusAspNetCoreOptions> so that any changes made to
         // PrometheusAspNetCoreOptions in deferred AddPrometheusExporter
@@ -114,7 +116,7 @@ public static IApplicationBuilder UseOpenTelemetryPrometheusScrapingEndpoint(
                 path = options.ScrapeEndpointPath ?? PrometheusAspNetCoreOptions.DefaultScrapeEndpointPath;
             }
 
-            if (!path.StartsWith("/"))
+            if (!path.StartsWith('/'))
             {
                 path = $"/{path}";
             }

src/OpenTelemetry.Exporter.Prometheus.AspNetCore/PrometheusExporterEndpointRouteBuilderExtensions.cs

@@ -69,6 +69,8 @@ public static IEndpointConventionBuilder MapPrometheusScrapingEndpoint(
         Action<IApplicationBuilder>? configureBranchedPipeline,
         string? optionsName)
     {
+        Guard.ThrowIfNull(endpoints);
+
         var builder = endpoints.CreateApplicationBuilder();
 
         // Note: Order is important here. MeterProvider is accessed before
@@ -84,7 +86,7 @@ public static IEndpointConventionBuilder MapPrometheusScrapingEndpoint(
             path = options.ScrapeEndpointPath ?? PrometheusAspNetCoreOptions.DefaultScrapeEndpointPath;
         }
 
-        if (!path.StartsWith("/"))
+        if (!path.StartsWith('/'))
         {
             path = $"/{path}";
         }

src/OpenTelemetry.Exporter.Prometheus.AspNetCore/PrometheusExporterMeterProviderBuilderExtensions.cs

@@ -62,9 +62,11 @@ public static MeterProviderBuilder AddPrometheusExporter(
         });
     }
 
-    private static MetricReader BuildPrometheusExporterMetricReader(PrometheusAspNetCoreOptions options)
+    private static BaseExportingMetricReader BuildPrometheusExporterMetricReader(PrometheusAspNetCoreOptions options)
     {
+#pragma warning disable CA2000 // Dispose objects before losing scope
         var exporter = new PrometheusExporter(options.ExporterOptions);
+#pragma warning restore CA2000 // Dispose objects before losing scope
 
         return new BaseExportingMetricReader(exporter)
         {

src/OpenTelemetry.Exporter.Prometheus.AspNetCore/PrometheusExporterMiddleware.cs

@@ -74,7 +74,7 @@ public async Task InvokeAsync(HttpContext httpContext)
                         ? "application/openmetrics-text; version=1.0.0; charset=utf-8"
                         : "text/plain; charset=utf-8; version=0.0.4";
 
-                    await response.Body.WriteAsync(dataView.Array!, 0, dataView.Count).ConfigureAwait(false);
+                    await response.Body.WriteAsync(dataView.Array.AsMemory(0, dataView.Count)).ConfigureAwait(false);
                 }
                 else
                 {

src/OpenTelemetry.Exporter.Prometheus.HttpListener/Internal/PrometheusCollectionManager.cs

@@ -34,8 +34,8 @@ public PrometheusCollectionManager(PrometheusExporter exporter)
         this.exporter = exporter;
         this.scrapeResponseCacheDurationMilliseconds = this.exporter.ScrapeResponseCacheDurationMilliseconds;
         this.onCollectRef = this.OnCollect;
-        this.metricsCache = new Dictionary<Metric, PrometheusMetric>();
-        this.scopes = new HashSet<string>();
+        this.metricsCache = [];
+        this.scopes = [];
     }
 
 #if NET
@@ -68,10 +68,7 @@ public Task<CollectionResponse> EnterCollect(bool openMetricsRequested)
         // If a collection is already running, return a task to wait on the result.
         if (this.collectionRunning)
         {
-            if (this.collectionTcs == null)
-            {
-                this.collectionTcs = new TaskCompletionSource<CollectionResponse>(TaskCreationOptions.RunContinuationsAsynchronously);
-            }
+            this.collectionTcs ??= new TaskCompletionSource<CollectionResponse>(TaskCreationOptions.RunContinuationsAsynchronously);
 
             Interlocked.Increment(ref this.readerCount);
             this.ExitGlobalLock();
@@ -148,6 +145,22 @@ public void ExitCollect()
         Interlocked.Decrement(ref this.readerCount);
     }
 
+    private static bool IncreaseBufferSize(ref byte[] buffer)
+    {
+        var newBufferSize = buffer.Length * 2;
+
+        if (newBufferSize > 100 * 1024 * 1024)
+        {
+            return false;
+        }
+
+        var newBuffer = new byte[newBufferSize];
+        buffer.CopyTo(newBuffer, 0);
+        buffer = newBuffer;
+
+        return true;
+    }
+
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     private void EnterGlobalLock()
     {
@@ -230,7 +243,7 @@ private ExportResult OnCollect(in Batch<Metric> metrics)
                             }
                             catch (IndexOutOfRangeException)
                             {
-                                if (!this.IncreaseBufferSize(ref buffer))
+                                if (!IncreaseBufferSize(ref buffer))
                                 {
                                     // there are two cases we might run into the following condition:
                                     // 1. we have many metrics to be exported - in this case we probably want
@@ -268,7 +281,7 @@ private ExportResult OnCollect(in Batch<Metric> metrics)
                     }
                     catch (IndexOutOfRangeException)
                     {
-                        if (!this.IncreaseBufferSize(ref buffer))
+                        if (!IncreaseBufferSize(ref buffer))
                         {
                             throw;
                         }
@@ -285,7 +298,7 @@ private ExportResult OnCollect(in Batch<Metric> metrics)
                 }
                 catch (IndexOutOfRangeException)
                 {
-                    if (!this.IncreaseBufferSize(ref buffer))
+                    if (!IncreaseBufferSize(ref buffer))
                     {
                         throw;
                     }
@@ -307,11 +320,11 @@ private ExportResult OnCollect(in Batch<Metric> metrics)
         {
             if (this.exporter.OpenMetricsRequested)
             {
-                this.previousOpenMetricsDataView = new ArraySegment<byte>(Array.Empty<byte>(), 0, 0);
+                this.previousOpenMetricsDataView = new ArraySegment<byte>([], 0, 0);
             }
             else
             {
-                this.previousPlainTextDataView = new ArraySegment<byte>(Array.Empty<byte>(), 0, 0);
+                this.previousPlainTextDataView = new ArraySegment<byte>([], 0, 0);
             }
 
             return ExportResult.Failure;
@@ -332,7 +345,7 @@ private int WriteTargetInfo(ref byte[] buffer)
                 }
                 catch (IndexOutOfRangeException)
                 {
-                    if (!this.IncreaseBufferSize(ref buffer))
+                    if (!IncreaseBufferSize(ref buffer))
                     {
                         throw;
                     }
@@ -343,22 +356,6 @@ private int WriteTargetInfo(ref byte[] buffer)
         return this.targetInfoBufferLength;
     }
 
-    private bool IncreaseBufferSize(ref byte[] buffer)
-    {
-        var newBufferSize = buffer.Length * 2;
-
-        if (newBufferSize > 100 * 1024 * 1024)
-        {
-            return false;
-        }
-
-        var newBuffer = new byte[newBufferSize];
-        buffer.CopyTo(newBuffer, 0);
-        buffer = newBuffer;
-
-        return true;
-    }
-
     private PrometheusMetric GetPrometheusMetric(Metric metric)
     {
         // Optimize writing metrics with bounded cache that has pre-calculated Prometheus names.

src/OpenTelemetry.Exporter.Prometheus.HttpListener/Internal/PrometheusMetric.cs

@@ -16,10 +16,10 @@ Histogram becomes histogram
        UpDownCounter becomes gauge
      * https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/data-model.md#otlp-metric-points-to-prometheus
     */
-    private static readonly PrometheusType[] MetricTypes = new PrometheusType[]
-    {
+    private static readonly PrometheusType[] MetricTypes =
+    [
         PrometheusType.Untyped, PrometheusType.Counter, PrometheusType.Gauge, PrometheusType.Summary, PrometheusType.Histogram, PrometheusType.Histogram, PrometheusType.Histogram, PrometheusType.Histogram, PrometheusType.Gauge,
-    };
+    ];
 
     public PrometheusMetric(string name, string unit, PrometheusType type, bool disableTotalNameSuffixForCounters)
     {
@@ -40,7 +40,7 @@ public PrometheusMetric(string name, string unit, PrometheusType type, bool disa
             // [OpenMetrics UNIT metadata](https://github.com/prometheus/OpenMetrics/blob/v1.0.0/specification/OpenMetrics.md#metricfamily)
             // and as a suffix to the metric name. The unit suffix comes before any type-specific suffixes.
             // https://github.com/open-telemetry/opentelemetry-specification/blob/3dfb383fe583e3b74a2365c5a1d90256b273ee76/specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1
-            if (!sanitizedName.EndsWith(sanitizedUnit))
+            if (!sanitizedName.EndsWith(sanitizedUnit, StringComparison.Ordinal))
             {
                 sanitizedName += $"_{sanitizedUnit}";
                 openMetricsName += $"_{sanitizedUnit}";
@@ -51,14 +51,14 @@ public PrometheusMetric(string name, string unit, PrometheusType type, bool disa
         // Exporters SHOULD provide a configuration option to disable the addition of `_total` suffixes.
         // https://github.com/open-telemetry/opentelemetry-specification/blob/b2f923fb1650dde1f061507908b834035506a796/specification/compatibility/prometheus_and_openmetrics.md#L286
         // Note that we no longer append '_ratio' for units that are '1', see: https://github.com/open-telemetry/opentelemetry-specification/issues/4058
-        if (type == PrometheusType.Counter && !sanitizedName.EndsWith("_total") && !disableTotalNameSuffixForCounters)
+        if (type == PrometheusType.Counter && !sanitizedName.EndsWith("_total", StringComparison.Ordinal) && !disableTotalNameSuffixForCounters)
         {
             sanitizedName += "_total";
         }
 
         // For counters requested using OpenMetrics format, the MetricFamily name MUST be suffixed with '_total', regardless of the setting to disable the 'total' suffix.
         // https://github.com/prometheus/OpenMetrics/blob/v1.0.0/specification/OpenMetrics.md#counter-1
-        if (type == PrometheusType.Counter && !openMetricsName.EndsWith("_total"))
+        if (type == PrometheusType.Counter && !openMetricsName.EndsWith("_total", StringComparison.Ordinal))
         {
             openMetricsName += "_total";
         }
@@ -127,7 +127,7 @@ internal static string SanitizeMetricName(string metricName)
 
         return sb?.ToString() ?? metricName;
 
-        static StringBuilder CreateStringBuilder(string name) => new StringBuilder(name.Length);
+        static StringBuilder CreateStringBuilder(string name) => new(name.Length);
     }
 
     internal static string RemoveAnnotations(string unit)
@@ -179,7 +179,7 @@ internal static string RemoveAnnotations(string unit)
 
     private static string SanitizeOpenMetricsName(string metricName)
     {
-        if (metricName.EndsWith("_total"))
+        if (metricName.EndsWith("_total", StringComparison.Ordinal))
         {
             return metricName.Substring(0, metricName.Length - 6);
         }

src/OpenTelemetry.Exporter.Prometheus.HttpListener/Internal/PrometheusSerializer.cs

@@ -17,8 +17,6 @@ internal static partial class PrometheusSerializer
 {
 #pragma warning disable SA1310 // Field name should not contain an underscore
     private const byte ASCII_QUOTATION_MARK = 0x22; // '"'
-    private const byte ASCII_FULL_STOP = 0x2E; // '.'
-    private const byte ASCII_HYPHEN_MINUS = 0x2D; // '-'
     private const byte ASCII_REVERSE_SOLIDUS = 0x5C; // '\\'
     private const byte ASCII_LINEFEED = 0x0A; // `\n`
 #pragma warning restore SA1310 // Field name should not contain an underscore

src/OpenTelemetry.Exporter.Prometheus.HttpListener/OpenTelemetry.Exporter.Prometheus.HttpListener.csproj

@@ -5,6 +5,7 @@
     <Description>Stand-alone HttpListener for hosting OpenTelemetry .NET Prometheus Exporter</Description>
     <PackageTags>$(PackageTags);prometheus;metrics</PackageTags>
     <MinVerTagPrefix>coreunstable-</MinVerTagPrefix>
+    <AnalysisLevel>latest-all</AnalysisLevel>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(RunningDotNetPack)' != 'true'">

src/OpenTelemetry.Exporter.Prometheus.HttpListener/PrometheusHttpListener.cs

@@ -30,12 +30,20 @@ public PrometheusHttpListener(PrometheusExporter exporter, PrometheusHttpListene
 
         string path = options.ScrapeEndpointPath ?? PrometheusHttpListenerOptions.DefaultScrapeEndpointPath;
 
-        if (!path.StartsWith("/"))
+#if NET
+        if (!path.StartsWith('/'))
+#else
+        if (!path.StartsWith("/", StringComparison.Ordinal))
+#endif
         {
             path = $"/{path}";
         }
 
-        if (!path.EndsWith("/"))
+#if NET
+        if (!path.EndsWith('/'))
+#else
+        if (!path.EndsWith("/", StringComparison.Ordinal))
+#endif
         {
             path = $"{path}/";
         }
@@ -164,7 +172,11 @@ private async Task ProcessRequestAsync(HttpListenerContext context)
                         ? "application/openmetrics-text; version=1.0.0; charset=utf-8"
                         : "text/plain; charset=utf-8; version=0.0.4";
 
-                    await context.Response.OutputStream.WriteAsync(dataView.Array!, 0, dataView.Count).ConfigureAwait(false);
+#if NET
+                    await context.Response.OutputStream.WriteAsync(dataView.Array.AsMemory(0, dataView.Count)).ConfigureAwait(false);
+#else
+                    await context.Response.OutputStream.WriteAsync(dataView.Array, 0, dataView.Count).ConfigureAwait(false);
+#endif
                 }
                 else
                 {

src/OpenTelemetry.Exporter.Prometheus.HttpListener/PrometheusHttpListenerMeterProviderBuilderExtensions.cs

@@ -62,7 +62,7 @@ public static MeterProviderBuilder AddPrometheusHttpListener(
         });
     }
 
-    private static MetricReader BuildPrometheusHttpListenerMetricReader(
+    private static BaseExportingMetricReader BuildPrometheusHttpListenerMetricReader(
         PrometheusHttpListenerOptions options)
     {
         var exporter = new PrometheusExporter(new PrometheusExporterOptions
@@ -78,8 +78,10 @@ private static MetricReader BuildPrometheusHttpListenerMetricReader(
 
         try
         {
+#pragma warning disable CA2000 // Dispose objects before losing scope
             var listener = new PrometheusHttpListener(exporter, options);
-            exporter.OnDispose = () => listener.Dispose();
+#pragma warning restore CA2000 // Dispose objects before losing scope
+            exporter.OnDispose = listener.Dispose;
             listener.Start();
         }
         catch (Exception ex)

src/OpenTelemetry/Metrics/Reader/BaseExportingMetricReader.cs

@@ -17,7 +17,6 @@ public class BaseExportingMetricReader : MetricReader
     /// </summary>
     protected readonly BaseExporter<Metric> exporter;
 
-    private readonly ExportModes supportedExportModes = ExportModes.Push | ExportModes.Pull;
     private readonly string exportCalledMessage;
     private readonly string exportSucceededMessage;
     private readonly string exportFailedMessage;
@@ -38,12 +37,12 @@ public BaseExportingMetricReader(BaseExporter<Metric> exporter)
         if (attributes.Length > 0)
         {
             var attr = (ExportModesAttribute)attributes[attributes.Length - 1];
-            this.supportedExportModes = attr.Supported;
+            this.SupportedExportModes = attr.Supported;
         }
 
         if (exporter is IPullMetricExporter pullExporter)
         {
-            if (this.supportedExportModes.HasFlag(ExportModes.Push))
+            if (this.SupportedExportModes.HasFlag(ExportModes.Push))
             {
                 pullExporter.Collect = this.Collect;
             }
@@ -69,7 +68,7 @@ public BaseExportingMetricReader(BaseExporter<Metric> exporter)
     /// <summary>
     /// Gets the supported <see cref="ExportModes"/>.
     /// </summary>
-    protected ExportModes SupportedExportModes => this.supportedExportModes;
+    protected ExportModes SupportedExportModes { get; } = ExportModes.Push | ExportModes.Pull;
 
     internal override void SetParentProvider(BaseProvider parentProvider)
     {
@@ -106,12 +105,12 @@ internal override bool ProcessMetrics(in Batch<Metric> metrics, int timeoutMilli
     /// <inheritdoc />
     protected override bool OnCollect(int timeoutMilliseconds)
     {
-        if (this.supportedExportModes.HasFlag(ExportModes.Push))
+        if (this.SupportedExportModes.HasFlag(ExportModes.Push))
         {
             return base.OnCollect(timeoutMilliseconds);
         }
 
-        if (this.supportedExportModes.HasFlag(ExportModes.Pull) && PullMetricScope.IsPullAllowed)
+        if (this.SupportedExportModes.HasFlag(ExportModes.Pull) && PullMetricScope.IsPullAllowed)
         {
             return base.OnCollect(timeoutMilliseconds);
         }

test/OpenTelemetry.Exporter.Prometheus.AspNetCore.Tests/OpenTelemetry.Exporter.Prometheus.AspNetCore.Tests.csproj

@@ -4,6 +4,7 @@
     <Description>Unit test project for Prometheus Exporter AspNetCore for OpenTelemetry</Description>
     <TargetFrameworks>$(TargetFrameworksForAspNetCoreTests)</TargetFrameworks>
     <DefineConstants>$(DefineConstants);PROMETHEUS_ASPNETCORE</DefineConstants>
+    <AnalysisLevel>latest-all</AnalysisLevel>
   </PropertyGroup>
 
   <ItemGroup>
@@ -28,7 +29,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Compile Include="$(RepoRoot)\test\OpenTelemetry.Exporter.Prometheus.HttpListener.Tests\EventSourceTest.cs" Link="Includes\EventSourceTest.cs" />
+    <Compile Include="$(RepoRoot)\test\OpenTelemetry.Exporter.Prometheus.HttpListener.Tests\EventSourceTests.cs" Link="Includes\EventSourceTests.cs" />
     <Compile Include="$(RepoRoot)\test\OpenTelemetry.Exporter.Prometheus.HttpListener.Tests\PrometheusCollectionManagerTests.cs" Link="Includes\PrometheusCollectionManagerTests.cs" />
     <Compile Include="$(RepoRoot)\test\OpenTelemetry.Exporter.Prometheus.HttpListener.Tests\PrometheusSerializerTests.cs" Link="Includes\PrometheusSerializerTests.cs" />