Elastic.CommonSchema.Log4net 9.0.0

Elastic Common Schema log4net Layout

This Layout implementation formats a log4net event into a JSON representation that adheres to the Elastic Common Schema specification.

Packages

The .NET assemblies are published to NuGet under the package name Elastic.CommonSchema.Log4net

How to use from configuration

Specify layout type in appender's configuration:

<log4net>
    <root>
        <level value="INFO" />
        <appender-ref ref="ConsoleAppender" />
    </root>
    <appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
        <layout type="Elastic.CommonSchema.Log4net.EcsLayout, Elastic.CommonSchema.Log4net" />
    </appender>
</log4net>

How to use from API

var hierarchy = (Hierarchy)LogManager.CreateRepository(Guid.NewGuid().ToString());
var appender = new ConsoleAppender { Layout = new EcsLayout() }; // Use the ECS layout.
hierarchy.Root.AddAppender(appender);
hierarchy.Root.Level = Level.All;
hierarchy.Configured = true;

The Layout = new EcsLayout() line then instructs log4net to use ECS layout. The sample above uses the console appender, but you are free to use any appender of your choice, perhaps consider using a filesystem target and Elastic Filebeat for durable and reliable ingestion.

ECS Aware Properties

Any valid ECS log template properties that is available under LogTemplateProperties.* e.g LogTemplateProperties.TraceId is supported and will directly set the appropriate ECS field.

Output

Apart from mandatory fields, the output contains additional data:

• labels is taken from metadata (string and boolean properties)
• log.origin.file.name is taken from LocationInformation
• log.origin.file.line is taken from LocationInformation
• log.origin.function is taken from LocationInformation
• event.created is taken from timestamp
• event.timezone is equal to local timezone
• host.hostname is taken from HostName property
• process.thread.id is taken from ThreadName if it has numeric value
• process.thread.name is taken from ThreadName if it doesn't have numeric value
• service.name is taken from entry or calling assembly
• service.version is taken from entry or calling assembly
• error.message is taken from ExceptionObject
• error.type is taken from ExceptionObject
• error.stacktrace is taken from ExceptionObject
• metadata is taken from properties. It also contains message template and arguments in case a formatted message was logged

Sample log event output (formatted for readability):

{
    "@timestamp": "2022-08-28T14:06:28.5121651+02:00",
    "log.level": "INFO",
    "message": "Hi! Welcome to example!",
    "ecs.version": "9.0.0",
    "log": {
        "logger": "Elastic.CommonSchema.Log4net.Example.Program",
        "original": null,
        "origin": {
            "file": {
                "name": "C:\\Development\\Elastic.CommonSchema.Log4net.Example\\Program.cs",
                "line": 17
            },
            "function": "Main"
        }
    },
    "labels": {
        "MessageTemplate": "{0}! Welcome to example!"
        "0": "Hi"
    },
    "agent": {
        "type": "Elastic.CommonSchema.Log4net.Example",
        "version": "1.0.0.0"
    },
    "event": {
        "created": "2024-04-02T17:43:55.3829964+02:00",
        "timezone": "W. Europe Standard Time"
    },
    "host": {
        "os": {
            "full": "Microsoft Windows 10.0.22631",
            "platform": "Win32NT",
            "version": "10.0.22631.0"
        },
        "architecture": "X64",
        "hostname": "HGU780D3",
        "name": "HGU780D3"
    },
    "process": {
        "name": "Elastic.CommonSchema.Log4net.Example",
        "pid": 39652,
        "thread.id": 17,
        "thread.name": ".NET Long Running Task",
        "title": ""
    },
    "service": {
        "name": "Elastic.CommonSchema.Log4net.Example",
        "type": "dotnet",
        "version": "1.0.0.0"
    },
    "user": {
        "domain": "company",
        "name": "user"
    },
    "metadata": {
        "GlobalAmountProperty": 3.14
    }
}

Copyright and License

This software is Copyright (c) 2014-2020 by Elasticsearch BV.

This is free software, licensed under: The Apache License Version 2.0.