5分で始める OpenTelemetry .NET ログ - コンソールアプリケーション

dotnet new console --output getting-started
cd getting-started
dotnet run

Hello World!

dotnet add package OpenTelemetry.Exporter.Console

using Microsoft.Extensions.Logging;
using OpenTelemetry;
using OpenTelemetry.Logs;

// OpenTelemetry を使用してロガーファクトリーを作成する
using var loggerFactory = LoggerFactory.Create(builder =>
{
    builder.AddOpenTelemetry(options =>
    {
        options.AddConsoleExporter();
    });
});

// ロガーインスタンスを取得する
var logger = loggerFactory.CreateLogger<Program>();

// シンプルなメッセージをログに記録する
logger.LogInformation("Hello from OpenTelemetry .NET Logs!");

// 構造化データを使ってログを記録する
logger.FoodPriceChanged("artichoke", 9.99);

// より複雑な例をログに記録する
logger.FoodRecallNotice(
    "Food & Beverages",
    "Contoso",
    "Salads",
    "Contoso Fresh Vegetables, Inc.",
    "due to a possible health risk from Listeria monocytogenes");

// 構造化ロギングのための拡張メソッドを定義する
internal static partial class LoggerExtensions
{
    [LoggerMessage(LogLevel.Information, "Food `{name}` price changed to `{price}`.")]
    public static partial void FoodPriceChanged(this ILogger logger, string name, double price);

    [LoggerMessage(LogLevel.Critical, "A `{productType}` recall notice was published for `{brandName} {productDescription}` produced by `{companyName}` ({recallReasonDescription}).")]
    public static partial void FoodRecallNotice(
        this ILogger logger,
        string productType,
        string brandName,
        string productDescription,
        string companyName,
        string recallReasonDescription);
}

LogRecord.Timestamp:               2023-09-15T06:07:03.5502083Z
LogRecord.CategoryName:            Program
LogRecord.Severity:                Info
LogRecord.SeverityText:            Information
LogRecord.Body:                    Food `{name}` price changed to `{price}`.
LogRecord.Attributes (Key:Value):
    name: artichoke
    price: 9.99
    OriginalFormat (a.k.a Body): Food `{name}` price changed to `{price}`.
LogRecord.EventId:                 344095174
LogRecord.EventName:               FoodPriceChanged

...

LogRecord.Timestamp:               2023-09-15T06:07:03.5683511Z
LogRecord.CategoryName:            Program
LogRecord.Severity:                Fatal
LogRecord.SeverityText:            Critical
LogRecord.Body:                    A `{productType}` recall notice was published for `{brandName} {productDescription}` produced by `{companyName}` ({recallReasonDescription}).
LogRecord.Attributes (Key:Value):
    brandName: Contoso
    productDescription: Salads
    productType: Food & Beverages
    recallReasonDescription: due to a possible health risk from Listeria monocytogenes
    companyName: Contoso Fresh Vegetables, Inc.
    OriginalFormat (a.k.a Body): A `{productType}` recall notice was published for `{brandName} {productDescription}` produced by `{companyName}` ({recallReasonDescription}).
LogRecord.EventId:                 1338249384
LogRecord.EventName:               FoodRecallNotice