SqlClient Instrumentation for OpenTelemetry

This is an Instrumentation Library, which instruments Microsoft.Data.SqlClient and System.Data.SqlClient and collects traces about database operations.

Steps to enable OpenTelemetry.Instrumentation.SqlClient

Step 1: Install Package

Add a reference to the OpenTelemetry.Instrumentation.SqlClient package. Also, add any other instrumentations & exporters you will need.

dotnet add package --prerelease OpenTelemetry.Instrumentation.SqlClient

Step 2: Enable SqlClient Instrumentation at application startup

SqlClient instrumentation must be enabled at application startup.

Traces

The following example demonstrates adding SqlClient traces instrumentation to a console application. This example also sets up the OpenTelemetry Console exporter, which requires adding the package OpenTelemetry.Exporter.Console to the application.

using OpenTelemetry.Trace;

public class Program
{
    public static void Main(string[] args)
    {
        using var tracerProvider = Sdk.CreateTracerProviderBuilder()
            .AddSqlClientInstrumentation()
            .AddConsoleExporter()
            .Build();
    }
}

Metrics

The following example demonstrates adding SqlClient metrics instrumentation to a console application. This example also sets up the OpenTelemetry Console exporter, which requires adding the package OpenTelemetry.Exporter.Console to the application.

using OpenTelemetry.Metrics;

public class Program
{
    public static void Main(string[] args)
    {
        using var tracerProvider = Sdk.CreateMeterProviderBuilder()
            .AddSqlClientInstrumentation()
            .AddConsoleExporter()
            .Build();
    }
}

List of metrics produced

The instrumentation is implemented based on metrics semantic conventions. Currently, the instrumentation supports the following metric.

ASP.NET Core

For an ASP.NET Core application, adding instrumentation is typically done in the ConfigureServices of your Startup class. Refer to documentation for OpenTelemetry.Instrumentation.AspNetCore.

ASP.NET

For an ASP.NET application, adding instrumentation is typically done in the Global.asax.cs. Refer to the documentation for OpenTelemetry.Instrumentation.AspNet.

Advanced configuration

This instrumentation can be configured to change the default behavior by using SqlClientTraceInstrumentationOptions.

SetDbStatementForText

SetDbStatementForText controls whether the db.statement attribute is emitted. The behavior of SetDbStatementForText depends on the runtime used, see below for more details.

Query text may contain sensitive data, so when SetDbStatementForText is enabled the raw query text is sanitized by automatically replacing literal values with a ? character.

.NET

On .NET, SetDbStatementForText controls whether or not this instrumentation will set the db.statement attribute to the CommandText of the SqlCommand being executed when the CommandType is CommandType.Text. The db.statement attribute is always captured for CommandType.StoredProcedure because the SqlCommand.CommandText only contains the stored procedure name.

SetDbStatementForText is false by default. When set to true, the instrumentation will set db.statement attribute to the text of the SQL command being executed.

To enable capturing of SqlCommand.CommandText for CommandType.Text use the following configuration.

using var tracerProvider = Sdk.CreateTracerProviderBuilder()
    .AddSqlClientInstrumentation(
        options => options.SetDbStatementForText = true)
    .AddConsoleExporter()
    .Build();

.NET Framework

On .NET Framework, there is no way to determine the type of command being executed, so the SetDbStatementForText property always controls whether or not this instrumentation will set the db.statement attribute to the CommandText of the SqlCommand being executed. The CommandText could be the name of a stored procedure (when CommandType.StoredProcedure is used) or the full text of a CommandType.Text query.

SetDbStatementForText is false by default. When set to true, the instrumentation will set db.statement attribute to the text of the SQL command being executed.

To enable capturing of SqlCommand.CommandText for CommandType.Text use the following configuration.

using var tracerProvider = Sdk.CreateTracerProviderBuilder()
    .AddSqlClientInstrumentation(
        options => options.SetDbStatementForText = true)
    .AddConsoleExporter()
    .Build();

Enrich

This option can be used to enrich the activity with additional information from the raw SqlCommand object. The Enrich action is called only when activity.IsAllDataRequested is true. It contains the activity itself (which can be enriched), the name of the event, and the actual raw object.

Currently there is only one event name reported, "OnCustom". The actual object is Microsoft.Data.SqlClient.SqlCommand for Microsoft.Data.SqlClient and System.Data.SqlClient.SqlCommand for System.Data.SqlClient.

The following code snippet shows how to add additional tags using Enrich.

using var tracerProvider = Sdk.CreateTracerProviderBuilder()
    .AddSqlClientInstrumentation(opt => opt.Enrich
        = (activity, eventName, rawObject) =>
    {
        if (eventName.Equals("OnCustom"))
        {
            if (rawObject is SqlCommand cmd)
            {
                activity.SetTag("db.commandTimeout", cmd.CommandTimeout);
            }
        };
    })
    .Build();

Processor, is the general extensibility point to add additional properties to any activity. The Enrich option is specific to this instrumentation, and is provided to get access to SqlCommand object.

RecordException

This option can be set to instruct the instrumentation to record SqlExceptions as Activity events.

The default value is false and can be changed by the code like below.

using var tracerProvider = Sdk.CreateTracerProviderBuilder()
    .AddSqlClientInstrumentation(
        options => options.RecordException = true)
    .AddConsoleExporter()
    .Build();

Filter

This option can be used to filter out activities based on the properties of the SqlCommand object being instrumented using a Func<object, bool>. The function receives an instance of the raw SqlCommand and should return true if the telemetry is to be collected, and false if it should not. The parameter of the Func delegate is of type object and needs to be cast to the appropriate type of SqlCommand, either Microsoft.Data.SqlClient.SqlCommand or System.Data.SqlClient.SqlCommand. The example below filters out all commands that are not stored procedures.

using var traceProvider = Sdk.CreateTracerProviderBuilder()
   .AddSqlClientInstrumentation(
       opt =>
       {
           opt.Filter = cmd =>
           {
               if (cmd is SqlCommand command)
               {
                   return command.CommandType == CommandType.StoredProcedure;
               }

               return false;
           };
       })
   .AddConsoleExporter()
   .Build();
{

Trace Context Propagation

Database trace context propagation can be enabled by setting OTEL_DOTNET_EXPERIMENTAL_SQLCLIENT_ENABLE_TRACE_CONTEXT_PROPAGATION environment variable to true. This uses the SET CONTEXT_INFO command to set traceparentinformation for the current connection, which results in an additional round-trip to the database.

References

• OpenTelemetry Project

• OpenTelemetry semantic conventions for database calls