Refactor OpenTelemetryEnvironment to use respsect specific endpoint variables for logs and traces.

Author: neistow

src/Serilog.Sinks.OpenTelemetry/Sinks/OpenTelemetry/Configuration/OpenTelemetryEnvironment.cs

@@ -16,49 +16,81 @@ namespace Serilog.Sinks.OpenTelemetry.Configuration;
 
 static class OpenTelemetryEnvironment
 {
-    const string ProtocolVarName = "OTEL_EXPORTER_OTLP_PROTOCOL";
-    const string EndpointVarName = "OTEL_EXPORTER_OTLP_ENDPOINT";
-    const string HeaderVarName = "OTEL_EXPORTER_OTLP_HEADERS";
-    const string ResourceAttributesVarName = "OTEL_RESOURCE_ATTRIBUTES";
-    const string ServiceNameVarName = "OTEL_SERVICE_NAME";
-
     public static void Configure(BatchedOpenTelemetrySinkOptions options, Func<string, string?> getConfigurationVariable)
     {
-        options.Protocol = getConfigurationVariable(ProtocolVarName) switch
-        {
-            "http/protobuf" => OtlpProtocol.HttpProtobuf,
-            "grpc" => OtlpProtocol.Grpc,
-            _ => options.Protocol
-        };
+        if (ParseProtocol(getConfigurationVariable(OpenTelemetryEnvironmentVariables.DefaultProtocol)) is { } protocol)
+            options.Protocol = protocol;
 
-        if (getConfigurationVariable(EndpointVarName) is { Length: > 1 } endpoint)
+        if (getConfigurationVariable(OpenTelemetryEnvironmentVariables.DefaultEndpoint) is { Length: > 1 } endpoint)
             options.Endpoint = endpoint;
 
-        FillHeadersIfPresent(getConfigurationVariable(HeaderVarName), options.Headers);
+        FillLogsConfigUsingSpecificationEnvVars(options, getConfigurationVariable);
 
-        FillHeadersResourceAttributesIfPresent(getConfigurationVariable(ResourceAttributesVarName), options.ResourceAttributes);
+        FillTracesConfigUsingSpecificationEnvVars(options, getConfigurationVariable);
 
-        if (getConfigurationVariable(ServiceNameVarName) is { Length: > 1 } serviceName)
+        FillDictionary(
+            options.Headers,
+            getConfigurationVariable,
+            OpenTelemetryEnvironmentVariables.DefaultHeaders);
+
+        FillDictionary(
+            options.ResourceAttributes,
+            getConfigurationVariable,
+            OpenTelemetryEnvironmentVariables.ResourceAttributes);
+
+        if (getConfigurationVariable(OpenTelemetryEnvironmentVariables.ServiceName) is { Length: > 1 } serviceName)
         {
             options.ResourceAttributes[SemanticConventions.AttributeServiceName] = serviceName;
         }
     }
 
-    static void FillHeadersIfPresent(string? config, IDictionary<string, string> headers)
+    static OtlpProtocol? ParseProtocol(string? protocol)
+    {
+        return protocol switch
+        {
+            "http/protobuf" => OtlpProtocol.HttpProtobuf,
+            "grpc" => OtlpProtocol.Grpc,
+            _ => null
+        };
+    }
+
+    static void FillLogsConfigUsingSpecificationEnvVars(
+        BatchedOpenTelemetrySinkOptions options,
+        Func<string, string?> getConfigurationVariable)
+    {
+        options.LogsEndpoint = getConfigurationVariable(OpenTelemetryEnvironmentVariables.LogsEndpoint);
+    }
+
+    static void FillTracesConfigUsingSpecificationEnvVars(
+        BatchedOpenTelemetrySinkOptions options,
+        Func<string, string?> getConfigurationVariable)
+    {
+        options.TracesEndpoint = getConfigurationVariable(OpenTelemetryEnvironmentVariables.TracesEndpoint);
+    }
+
+    static void FillDictionary(
+        IDictionary<string, string> dictionary,
+        Func<string, string?> getConfigurationVariable,
+        string environmentVariableName)
     {
+        var config = getConfigurationVariable(environmentVariableName);
         if (config == null) return;
-        foreach (var (key, value) in BaggageFormat.DecodeBaggageString(config, HeaderVarName))
+        foreach (var (key, value) in BaggageFormat.DecodeBaggageString(config, environmentVariableName))
         {
-            headers[key] = value;
+            dictionary[key] = value;
         }
     }
 
-    static void FillHeadersResourceAttributesIfPresent(string? config, IDictionary<string, object> resourceAttributes)
+    static void FillDictionary(
+        IDictionary<string, object> dictionary,
+        Func<string, string?> getConfigurationVariable,
+        string environmentVariableName)
     {
+        var config = getConfigurationVariable(environmentVariableName);
         if (config == null) return;
-        foreach (var (key, value) in BaggageFormat.DecodeBaggageString(config, ResourceAttributesVarName))
+        foreach (var (key, value) in BaggageFormat.DecodeBaggageString(config, environmentVariableName))
         {
-            resourceAttributes[key] = value;
+            dictionary[key] = value;
         }
     }
-}
+}

src/Serilog.Sinks.OpenTelemetry/Sinks/OpenTelemetry/Configuration/OpenTelemetryEnvironmentVariables.cs

@@ -0,0 +1,15 @@
+namespace Serilog.Sinks.OpenTelemetry.Configuration;
+
+static class OpenTelemetryEnvironmentVariables
+{
+    public const string DefaultEndpoint = "OTEL_EXPORTER_OTLP_ENDPOINT";
+    public const string DefaultHeaders = "OTEL_EXPORTER_OTLP_HEADERS";
+    public const string DefaultProtocol = "OTEL_EXPORTER_OTLP_PROTOCOL";
+
+    public const string LogsEndpoint = "OTEL_EXPORTER_OTLP_LOGS_ENDPOINT";
+ 
+    public const string TracesEndpoint = "OTEL_EXPORTER_OTLP_TRACES_ENDPOINT";
+ 
+    public const string ServiceName = "OTEL_SERVICE_NAME";
+    public const string ResourceAttributes = "OTEL_RESOURCE_ATTRIBUTES";
+}

test/Serilog.Sinks.OpenTelemetry.Tests/OpenTelemetryEnvironmentTests.cs

@@ -5,6 +5,31 @@ namespace Serilog.Sinks.OpenTelemetry.Tests;
 
 public class OpenTelemetryEnvironmentTests
 {
+    [Fact]
+    public void ConfigureRespectsSpecificEndpointEnvironmentVariableValues()
+    {
+        BatchedOpenTelemetrySinkOptions options = new();
+        
+        var generalEndpoint = "http://general";
+        var logSpecificEndpoint = "http://log-specific";
+        var tracesSpecificEndpoint = "http://traces-specific";
+        
+        OpenTelemetryEnvironment.Configure(options, GetEnvVar);
+        
+        Assert.Equal(generalEndpoint, options.Endpoint);
+        Assert.Equal(logSpecificEndpoint, options.LogsEndpoint);
+        Assert.Equal(tracesSpecificEndpoint, options.TracesEndpoint);
+        return;
+
+        string? GetEnvVar(string name) => name switch
+        {
+            OpenTelemetryEnvironmentVariables.DefaultEndpoint => generalEndpoint,
+            OpenTelemetryEnvironmentVariables.LogsEndpoint => logSpecificEndpoint,
+            OpenTelemetryEnvironmentVariables.TracesEndpoint => tracesSpecificEndpoint,
+            _ => null
+        };
+    }
+    
     [Fact]
     public void ConfigureFillsOptionsWithEnvironmentVariableValues()
     {
@@ -30,11 +55,11 @@ public void ConfigureFillsOptionsWithEnvironmentVariableValues()
 
         string? GetEnvVar(string name) => name switch
         {
-            "OTEL_EXPORTER_OTLP_ENDPOINT" => endpoint,
-            "OTEL_EXPORTER_OTLP_HEADERS" => headers,
-            "OTEL_RESOURCE_ATTRIBUTES" => resourceAttributes,
-            "OTEL_EXPORTER_OTLP_PROTOCOL" => "grpc",
-            "OTEL_SERVICE_NAME" => serviceName,
+            OpenTelemetryEnvironmentVariables.DefaultEndpoint => endpoint,
+            OpenTelemetryEnvironmentVariables.DefaultHeaders => headers,
+            OpenTelemetryEnvironmentVariables.ResourceAttributes => resourceAttributes,
+            OpenTelemetryEnvironmentVariables.DefaultProtocol => "grpc",
+            OpenTelemetryEnvironmentVariables.ServiceName => serviceName,
             _ => null
         };
     }
@@ -54,8 +79,8 @@ public void ExplicitServiceNameOverridesResourceAttribute()
 
         string? GetEnvVar(string name) => name switch
         {
-            "OTEL_RESOURCE_ATTRIBUTES" => resourceAttributes,
-            "OTEL_SERVICE_NAME" => serviceName,
+            OpenTelemetryEnvironmentVariables.ResourceAttributes => resourceAttributes,
+            OpenTelemetryEnvironmentVariables.ServiceName => serviceName,
             _ => null
         };
     }
@@ -76,8 +101,8 @@ public void ConfigureAppendPathToEndpointIfProtocolIsHttpProtobufAndEndpointDoes
         string? GetEnvVar(string name)
              => name switch
              {
-                 "OTEL_EXPORTER_OTLP_ENDPOINT" => endpoint,
-                 "OTEL_EXPORTER_OTLP_PROTOCOL" => "http/protobuf",
+                 OpenTelemetryEnvironmentVariables.DefaultEndpoint => endpoint,
+                 OpenTelemetryEnvironmentVariables.DefaultProtocol => "http/protobuf",
                  _ => null
              };
     }
@@ -95,7 +120,7 @@ public void ConfigureThrowsIfHeaderEnvIsInvalidFormat()
         string? GetEnvVar(string name)
              => name switch
              {
-                 "OTEL_EXPORTER_OTLP_HEADERS" => headers,
+                 OpenTelemetryEnvironmentVariables.DefaultHeaders => headers,
                  _ => null
              };
     }
@@ -113,7 +138,7 @@ public void ConfigureThrowsIfResourceAttributesEnvIsInvalidFormat()
         string? GetEnvVar(string name)
              => name switch
              {
-                 "OTEL_RESOURCE_ATTRIBUTES" => resourceAttributes,
+                 OpenTelemetryEnvironmentVariables.ResourceAttributes => resourceAttributes,
                  _ => null
              };
     }