Logfmt.net

Project Intro

logfmt.net is intended to be a simple & lightweight structured logging library for .net applications.

Goals:

• Support the logfmt output format.
• Enable the practice of structured logging.
• Provide space delimited or json encoding of output.
• Sending output to default console stream or any other provided stream.

Non-Goals:

• Managing file rollovers
• Data routing rules & filters
• Output templates

Installation

Binary distribution of this library is available in a nuget package. Run the following command to install it:

dotnet add package logfmt.net --version 0.0.4-alpha

Note: this requires the .NET CLI tool. Other installation methods for nuget packages are available on the package page @ https://www.nuget.org/packages/logfmt.net

Building the source

Running make all in a shell from the root directory of this repository will build the library and execute the tests. It uses the dotnet command, so the .NET CLI tool must be installed.

Using the library

To use the logfmt logger, create a new instance of the Logger class:

var log = new logfmt.Logger();
log.Info("hello logs!");

The default contructor will send the log output to the console output stream. There is an overload for the constructor to provide a different stream to send output to.

All of the severity log methods (Debug,Info,Warn,Error) accept KeyValuePair<string,string> params in addition to the log message. This enables the logging of structured data outside of the log message string.

var log = new logfmt.Logger();
log.Info("hello logs!", new KeyValuePair<string,string>("foo","bar"),new KeyValuePair<string,string>("bar","foo"));

If there is a key value pair that is needed on every logging call, the WithData method can register it for all future calls in the instance.

var log = new logfmt.Logger().WithData(new KeyValuePair<string,string>("foo","bar"));
// the Info call below will have foo=bar added to the output 
log.Info("hello logs!");

Contributions

Contributions are welcomed & encouraged! If there is something missing or broken please feel free to write an issue, or submit a PR.