[FileBasedConfiguration] Resources

src/OpenTelemetry.AutoInstrumentation/Configurations/ConfigurationKeys.cs

@@ -51,6 +51,33 @@ internal partial class ConfigurationKeys
     /// </summary>
     public const string EnabledResourceDetectorTemplate = "OTEL_DOTNET_AUTO_{0}_RESOURCE_DETECTOR_ENABLED";
 
+    /// <summary>
+    /// Configuration key template for resource attributes.
+    /// </summary>
+    public const string ResourceAttributes = "OTEL_RESOURCE_ATTRIBUTES";
+
+    /// <summary>
+    /// Configuration key for setting the service name.
+    /// </summary>
+    public const string ServiceName = "OTEL_SERVICE_NAME";
+
+    /// <summary>
+    /// Configuration keys for file based configuration.
+    /// </summary>
+    public static class FileBasedConfiguration
+    {
+        /// <summary>
+        /// Configuration key for enabling file based configuration.
+        /// </summary>
+        public const string Enabled = "OTEL_EXPERIMENTAL_FILE_BASED_CONFIGURATION_ENABLED";
+
+        /// <summary>
+        /// Configuration key for the path to the configuration file.
+        /// Default is <c>"config.yaml"</c>.
+        /// </summary>
+        public const string FileName = "OTEL_EXPERIMENTAL_CONFIG_FILE";
+    }
+
     /// <summary>
     /// Configuration keys for traces.
     /// </summary>

src/OpenTelemetry.AutoInstrumentation/Configurations/FailFastSettings.cs

@@ -7,7 +7,7 @@ internal class FailFastSettings : Settings
 {
     public bool FailFast { get; private set; }
 
-    protected override void OnLoad(Configuration configuration)
+    protected override void OnLoadEnvVar(Configuration configuration)
     {
         FailFast = configuration.GetBool(ConfigurationKeys.FailFast) ?? false;
     }

src/OpenTelemetry.AutoInstrumentation/Configurations/FileBasedConfiguration/Parser/ConditionalDeserializer.cs

@@ -1,7 +1,6 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-using System.Reflection;
 using Vendors.YamlDotNet.Core;
 using Vendors.YamlDotNet.Core.Events;
 using Vendors.YamlDotNet.Serialization;

src/OpenTelemetry.AutoInstrumentation/Configurations/FileBasedConfiguration/Parser/EmptyObjectOnEmptyYamlAttribute.cs

@@ -4,6 +4,4 @@
 namespace OpenTelemetry.AutoInstrumentation.Configurations.FileBasedConfiguration.Parser;
 
 [AttributeUsage(AttributeTargets.Class)]
-internal sealed class EmptyObjectOnEmptyYamlAttribute : Attribute
-{
-}
+internal sealed class EmptyObjectOnEmptyYamlAttribute : Attribute;

src/OpenTelemetry.AutoInstrumentation/Configurations/FileBasedConfiguration/Parser/Parser.cs

@@ -0,0 +1,23 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+using Vendors.YamlDotNet.Serialization;
+using Vendors.YamlDotNet.Serialization.NodeDeserializers;
+
+namespace OpenTelemetry.AutoInstrumentation.Configurations.FileBasedConfiguration.Parser;
+
+internal static class Parser
+{
+    public static YamlConfiguration ParseYaml(string filePath)
+    {
+        var deserializer = new DeserializerBuilder()
+            .WithNodeDeserializer(existing => new ConditionalDeserializer(existing), s => s.InsteadOf<NullNodeDeserializer>())
+            .WithTypeConverter(new EnvVarTypeConverter())
+            .IgnoreUnmatchedProperties()
+            .Build();
+
+        var yaml = File.ReadAllText(filePath);
+        var config = deserializer.Deserialize<YamlConfiguration>(yaml);
+        return config;
+    }
+}

src/OpenTelemetry.AutoInstrumentation/Configurations/FileBasedConfiguration/ResourceAttribute.cs

@@ -0,0 +1,27 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+using Vendors.YamlDotNet.Serialization;
+
+namespace OpenTelemetry.AutoInstrumentation.Configurations.FileBasedConfiguration;
+
+internal class ResourceAttribute
+{
+    /// <summary>
+    /// Gets or sets the name of the resource attribute.
+    /// </summary>
+    [YamlMember(Alias = "name")]
+    public string Name { get; set; } = null!;
+
+    /// <summary>
+    /// Gets or sets the value of the resource attribute.
+    /// </summary>
+    [YamlMember(Alias = "value")]
+    public object Value { get; set; } = null!;
+
+    /// <summary>
+    /// Gets or sets the type of the resource attribute.
+    /// </summary>
+    [YamlMember(Alias = "type")]
+    public string Type { get; set; } = "string";
+}

src/OpenTelemetry.AutoInstrumentation/Configurations/FileBasedConfiguration/ResourceConfiguration.cs

@@ -0,0 +1,63 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+using Vendors.YamlDotNet.Serialization;
+
+namespace OpenTelemetry.AutoInstrumentation.Configurations.FileBasedConfiguration;
+
+internal class ResourceConfiguration
+{
+    /// <summary>
+    /// Gets or sets the list of resource attributes.
+    /// </summary>
+    [YamlMember(Alias = "attributes")]
+    public List<ResourceAttribute>? Attributes { get; set; }
+
+    /// <summary>
+    /// Gets or sets the attributes list for the resource.
+    /// </summary>
+    [YamlMember(Alias = "attributes_list")]
+    public string? AttributesList { get; set; }
+
+    public List<KeyValuePair<string, object>> ParseAttributes()
+    {
+        var resourceAttributesWithPriority = new Dictionary<string, object>();
+
+        if (Attributes != null)
+        {
+            foreach (var attr in Attributes)
+            {
+                if (!resourceAttributesWithPriority.ContainsKey(attr.Name))
+                {
+                    // TODO parse type and converting the value accordingly.
+                    resourceAttributesWithPriority.Add(attr.Name, attr.Value);
+                }
+            }
+        }
+
+        if (AttributesList != null)
+        {
+            const char attributeListSplitter = ',';
+            char[] attributeKeyValueSplitter = ['='];
+
+            var rawAttributes = AttributesList.Split(attributeListSplitter);
+            foreach (var rawKeyValuePair in rawAttributes)
+            {
+                var keyValuePair = rawKeyValuePair.Split(attributeKeyValueSplitter, 2);
+                if (keyValuePair.Length != 2)
+                {
+                    continue;
+                }
+
+                var key = keyValuePair[0].Trim();
+
+                if (!resourceAttributesWithPriority.ContainsKey(key))
+                {
+                    resourceAttributesWithPriority.Add(key, keyValuePair[1].Trim());
+                }
+            }
+        }
+
+        return resourceAttributesWithPriority.ToList();
+    }
+}

src/OpenTelemetry.AutoInstrumentation/Configurations/FileBasedConfiguration/YamlConfiguration.cs

@@ -0,0 +1,25 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+using Vendors.YamlDotNet.Serialization;
+
+namespace OpenTelemetry.AutoInstrumentation.Configurations.FileBasedConfiguration;
+
+internal class YamlConfiguration
+{
+    /// <summary>
+    /// Gets or sets the file format version.
+    /// The yaml format is documented at
+    /// https://github.com/open-telemetry/opentelemetry-configuration/tree/main/schema
+    /// </summary>
+    [YamlMember(Alias = "file_format")]
+    public string? FileFormat { get; set; }
+
+    /// <summary>
+    /// Gets or sets the resource configuration.
+    /// Configure resource for all signals.
+    /// If omitted, the default resource is used.
+    /// </summary>
+    [YamlMember(Alias = "resource")]
+    public ResourceConfiguration? Resource { get; set; }
+}

src/OpenTelemetry.AutoInstrumentation/Configurations/GeneralSettings.cs

@@ -10,11 +10,6 @@ internal class GeneralSettings : Settings
     /// </summary>
     public IList<string> Plugins { get; } = new List<string>();
 
-    /// <summary>
-    /// Gets the list of enabled resource detectors.
-    /// </summary>
-    public IReadOnlyList<ResourceDetector> EnabledResourceDetectors { get; private set; } = new List<ResourceDetector>();
-
     /// <summary>
     /// Gets a value indicating whether the <see cref="AppDomain.UnhandledException"/> event should trigger
     /// the flushing of telemetry data.
@@ -32,7 +27,7 @@ internal class GeneralSettings : Settings
     /// </summary>
     public bool ProfilerEnabled { get; private set; }
 
-    protected override void OnLoad(Configuration configuration)
+    protected override void OnLoadEnvVar(Configuration configuration)
     {
         var providerPlugins = configuration.GetString(ConfigurationKeys.ProviderPlugins);
         if (providerPlugins != null)
@@ -43,12 +38,6 @@ protected override void OnLoad(Configuration configuration)
             }
         }
 
-        var resourceDetectorsEnabledByDefault = configuration.GetBool(ConfigurationKeys.ResourceDetectorEnabled) ?? true;
-
-        EnabledResourceDetectors = configuration.ParseEnabledEnumList<ResourceDetector>(
-            enabledByDefault: resourceDetectorsEnabledByDefault,
-            enabledConfigurationTemplate: ConfigurationKeys.EnabledResourceDetectorTemplate);
-
         FlushOnUnhandledException = configuration.GetBool(ConfigurationKeys.FlushOnUnhandledException) ?? false;
         SetupSdk = configuration.GetBool(ConfigurationKeys.SetupSdk) ?? true;
 

src/OpenTelemetry.AutoInstrumentation/Configurations/LogSettings.cs

@@ -43,7 +43,7 @@ internal class LogSettings : Settings
     /// </summary>
     public OtlpSettings? OtlpSettings { get; private set; }
 
-    protected override void OnLoad(Configuration configuration)
+    protected override void OnLoadEnvVar(Configuration configuration)
     {
         LogsEnabled = configuration.GetBool(ConfigurationKeys.Logs.LogsEnabled) ?? true;
         LogExporters = ParseLogExporter(configuration);

src/OpenTelemetry.AutoInstrumentation/Configurations/MetricSettings.cs

@@ -38,7 +38,7 @@ internal class MetricSettings : Settings
     /// </summary>
     public OtlpSettings? OtlpSettings { get; private set; }
 
-    protected override void OnLoad(Configuration configuration)
+    protected override void OnLoadEnvVar(Configuration configuration)
     {
         MetricExporters = ParseMetricExporter(configuration);
         if (MetricExporters.Contains(MetricsExporter.Otlp))

src/OpenTelemetry.AutoInstrumentation/Configurations/ResourceConfigurator.cs

@@ -8,21 +8,24 @@ namespace OpenTelemetry.AutoInstrumentation.Configurations;
 
 internal static class ResourceConfigurator
 {
-    internal const string ServiceNameAttribute = "service.name";
-
-    public static ResourceBuilder CreateResourceBuilder(IReadOnlyList<ResourceDetector> enabledResourceDetectors)
+    public static ResourceBuilder CreateResourceBuilder(ResourceSettings resourceSettings)
     {
         var resourceBuilder = ResourceBuilder
-            .CreateEmpty() // Don't use CreateDefault because it puts service name unknown by default.
-            .AddEnvironmentVariableDetector()
-            .AddTelemetrySdk()
-            .AddAttributes(new KeyValuePair<string, object>[]
-            {
+            .CreateEmpty(); // Don't use CreateDefault because it puts service name unknown by default.
+
+        if (resourceSettings.EnvironmentalVariablesDetectorEnabled)
+        {
+            resourceBuilder.AddEnvironmentVariableDetector();
+        }
+
+        resourceBuilder.AddTelemetrySdk()
+            .AddAttributes([
                 new(Constants.DistributionAttributes.TelemetryDistroNameAttributeName, Constants.DistributionAttributes.TelemetryDistroNameAttributeValue),
                 new(Constants.DistributionAttributes.TelemetryDistroVersionAttributeName, AutoInstrumentationVersion.Version)
-            });
+            ])
+            .AddAttributes(resourceSettings.Resources);
 
-        foreach (var enabledResourceDetector in enabledResourceDetectors)
+        foreach (var enabledResourceDetector in resourceSettings.EnabledDetectors)
         {
             resourceBuilder = enabledResourceDetector switch
             {
@@ -39,10 +42,10 @@ public static ResourceBuilder CreateResourceBuilder(IReadOnlyList<ResourceDetect
         }
 
         var resource = resourceBuilder.Build();
-        if (!resource.Attributes.Any(kvp => kvp.Key == ServiceNameAttribute))
+        if (resource.Attributes.All(kvp => kvp.Key != Constants.ResourceAttributes.AttributeServiceName))
         {
             // service.name was not configured yet use the fallback.
-            resourceBuilder.AddAttributes(new KeyValuePair<string, object>[] { new(ServiceNameAttribute, ServiceNameConfigurator.GetFallbackServiceName()) });
+            resourceBuilder.AddAttributes([new(Constants.ResourceAttributes.AttributeServiceName, ServiceNameConfigurator.GetFallbackServiceName())]);
         }
 
         var pluginManager = Instrumentation.PluginManager;

src/OpenTelemetry.AutoInstrumentation/Configurations/ResourceSettings.cs

@@ -0,0 +1,42 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+using OpenTelemetry.AutoInstrumentation.Configurations.FileBasedConfiguration;
+
+namespace OpenTelemetry.AutoInstrumentation.Configurations;
+
+internal class ResourceSettings : Settings
+{
+    /// <summary>
+    /// Gets or sets the list of enabled resource detectors.
+    /// </summary>
+    public IReadOnlyList<ResourceDetector> EnabledDetectors { get; set; } = [];
+
+    /// <summary>
+    /// Gets or sets the list of enabled resources.
+    /// </summary>
+    public IReadOnlyList<KeyValuePair<string, object>> Resources { get; set; } = [];
+
+    /// <summary>
+    /// Gets or sets a value indicating whether environmental variables resource detector is enabled.
+    /// </summary>
+    public bool EnvironmentalVariablesDetectorEnabled { get; set; } = true;
+
+    protected override void OnLoadEnvVar(Configuration configuration)
+    {
+        var resourceDetectorsEnabledByDefault = configuration.GetBool(ConfigurationKeys.ResourceDetectorEnabled) ?? true;
+
+        EnabledDetectors = configuration.ParseEnabledEnumList<ResourceDetector>(
+            enabledByDefault: resourceDetectorsEnabledByDefault,
+            enabledConfigurationTemplate: ConfigurationKeys.EnabledResourceDetectorTemplate);
+    }
+
+    protected override void OnLoadFile(YamlConfiguration configuration)
+    {
+        EnvironmentalVariablesDetectorEnabled = false;
+
+        Resources = configuration.Resource?.ParseAttributes() ?? [];
+
+        // TODO initialize EnabledDetectors from file configuration
+    }
+}

src/OpenTelemetry.AutoInstrumentation/Configurations/SdkSettings.cs

@@ -1,7 +1,6 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-using System.Diagnostics.CodeAnalysis;
 using OpenTelemetry.AutoInstrumentation.Logging;
 
 namespace OpenTelemetry.AutoInstrumentation.Configurations;
@@ -18,7 +17,7 @@ internal class SdkSettings : Settings
     /// </summary>
     public IList<Propagator> Propagators { get; private set; } = new List<Propagator>();
 
-    protected override void OnLoad(Configuration configuration)
+    protected override void OnLoadEnvVar(Configuration configuration)
     {
         Propagators = ParsePropagator(configuration);
     }