Observability

OpenTelemetry is the open-source standard for distributed tracing. SolrNet offers OpenTelemetry Tracing support out-of-the-box.

Tracing

ASP.NET Core application

This example is using the following packages:

• OpenTelemetry.Extensions.Hosting
• OpenTelemetry.Exporter.Console

var builder = WebApplication.CreateBuilder(args);

void ConfigureResource(ResourceBuilder r)
{
    r.AddService("Service Name",
        serviceVersion: "Version",
        serviceInstanceId: Environment.MachineName);
}

builder.Services.AddOpenTelemetry()
    .ConfigureResource(ConfigureResource)
    .WithTracing(b => b
        .AddSource(SolrNet.DiagnosticHeaders.DefaultSourceName) // SolrNet ActivitySource
        .AddConsoleExporter() // Any OTEL supportable exporter can be used here
    );

Console application

This example is using the following packages:

• OpenTelemetry
• OpenTelemetry.Exporter.Console

void ConfigureResource(ResourceBuilder r)
{
    r.AddService("Service Name",
        serviceVersion: "Version",
        serviceInstanceId: Environment.MachineName);
}

using var tracerProvider = Sdk.CreateTracerProviderBuilder()
    .ConfigureResource(ConfigureResource)
    .AddSource(SolrNet.DiagnosticHeaders.DefaultSourceName) // SolrNet ActivitySource
    .AddConsoleExporter() // Any OTEL supportable exporter can be used here
    .Build();

SolrNet spans contain the following attributes:

Attribute	Description	Examples
db.system	The database product identifier	solr
db.collection.name	The solr core being targeted (optional)	techproducts
db.query.text	The request parameters as a json string (optional)	[{"q":"ipad"},{"rows":"100"},{"fq":"price:[0 TO 8]"},{"facet":"true"},{"facet.field":"cat"},{"sort":"price asc"}]
db.operation.name	The name of the operation or command being executed	query, commit, add, delete, ...
http.request.method	The underlying HTTP request method	GET, POST
server.address	Host name of the solr server	localhost
server.port	Port of the solr server	8983
url.full	The full underlying request URL	http://localhost:8983/solr/techproducts/select?q=ipad&rows=100&fq=price%3A%5B0+TO+8%5D&facet=true&facet.field=cat&sort=price+asc&version=2.2&wt=xml
solr.status	Status header from the solr response (optional)	0 means success
solr.qtime	Query time header from the solr response (optional)	42
error.type	Error message (optional)	The remote server returned an error: (404) Not Found.