chore(): Decoupling OTEL_EXPORTER_OTLP_CERTIFICATE from mTLS

Author: sandy2008

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/OpenTelemetryProtocolExporterEventSource.cs

@@ -325,5 +325,28 @@ internal void MtlsHttpClientCreationFailed(Exception ex)
         Level = EventLevel.Error)]
     internal void MtlsHttpClientCreationFailed(string exception) =>
         this.WriteEvent(34, exception);
+
+    [Event(
+        35,
+        Message = "CA certificate configured for server validation. Subject: '{0}'.",
+        Level = EventLevel.Informational)]
+    internal void CaCertificateConfigured(string subject) =>
+        this.WriteEvent(35, subject);
+
+    [NonEvent]
+    internal void SecureHttpClientCreationFailed(Exception ex)
+    {
+        if (Log.IsEnabled(EventLevel.Error, EventKeywords.All))
+        {
+            this.SecureHttpClientCreationFailed(ex.ToInvariantString());
+        }
+    }
+
+    [Event(
+        36,
+        Message = "Failed to create secure HttpClient. Exception: {0}",
+        Level = EventLevel.Error)]
+    internal void SecureHttpClientCreationFailed(string exception) =>
+        this.WriteEvent(36, exception);
 #endif
 }

…ementation/OtlpMtlsCertificateManager.cs …Implementation/OtlpCertificateManager.cssrc/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/OtlpMtlsCertificateManager.cs renamed to src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/OtlpCertificateManager.cs src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/OtlpMtlsCertificateManager.cs renamed to src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/OtlpCertificateManager.cs

@@ -10,9 +10,13 @@
 namespace OpenTelemetry.Exporter.OpenTelemetryProtocol.Implementation;
 
 /// <summary>
-/// Manages certificate loading, validation, and security checks for mTLS connections.
+/// Manages certificate loading, validation, and security checks for TLS connections.
 /// </summary>
-internal static class OtlpMtlsCertificateManager
+/// <remarks>
+/// This class provides functionality for both simple server certificate trust
+/// (for self-signed certificates) and mTLS client authentication scenarios.
+/// </remarks>
+internal static class OtlpCertificateManager
 {
     internal const string CaCertificateType = "CA certificate";
     internal const string ClientCertificateType = "Client certificate";
@@ -21,8 +25,8 @@ internal static class OtlpMtlsCertificateManager
     /// <summary>
     /// Loads a CA certificate from a PEM file.
     /// </summary>
-    /// <param name="caCertificatePath">Path to the CA certificate file.</param>
-    /// <returns>The loaded CA certificate.</returns>
+    /// <param name="caCertificatePath">Path to the certificate file.</param>
+    /// <returns>The loaded certificate.</returns>
     /// <exception cref="FileNotFoundException">Thrown when the certificate file is not found.</exception>
     /// <exception cref="InvalidOperationException">Thrown when the certificate cannot be loaded.</exception>
     public static X509Certificate2 LoadCaCertificate(string caCertificatePath)
@@ -218,6 +222,10 @@ public static bool ValidateCertificateChain(
     /// <param name="sslPolicyErrors">The SSL policy errors.</param>
     /// <param name="caCertificate">The CA certificate to validate against.</param>
     /// <returns>True if the certificate is valid; otherwise, false.</returns>
+    /// <remarks>
+    /// This method is used to validate server certificates against a CA certificate.
+    /// Common use case: connecting to a server with a self-signed certificate.
+    /// </remarks>
     internal static bool ValidateServerCertificate(
         X509Certificate2 serverCert,
         X509Chain chain,
@@ -232,7 +240,7 @@ internal static bool ValidateServerCertificate(
                 return true;
             }
 
-            // If the only error is an untrusted root, validate against our CA
+            // If the only error is an untrusted root, validate against our CA certificate
             if (sslPolicyErrors.HasFlag(SslPolicyErrors.RemoteCertificateChainErrors))
             {
                 // Add our CA certificate to the chain
@@ -248,7 +256,7 @@ internal static bool ValidateServerCertificate(
 
                 if (isValid)
                 {
-                    // Verify that the chain terminates with our CA
+                    // Verify that the chain terminates with our CA certificate
                     var rootCert = chain.ChainElements[^1].Certificate;
                     if (
                         string.Equals(