Loggers in C#
Introduction
The majority of developers utilize any or all of the many logging libraries and frameworks that are available daily. Off the top of my head, here are a few examples. Serilog, NLog, Elmah, and Log4Net are all examples of net developers. For developers involved in debugging code, they are straightforward, simple, and effective. The use of just these instruments is insufficient. The logger management and error tracking product from Stackify includes many of the best practices we'll discuss in this post for dealing with common problems with log files.
Logging frameworks
Usually, logging frameworks encourage the following features:
- measuring levels
- logging objectives
- Structured, also referred to as "semantic" logging,
NLog
One of the most well-liked and effective entry frameworks for.NET is NLog. It is not too difficult to set up NLog. Dependencies can be downloaded using Nuget, and targets can be set up by editing the NLog.config file. For log data, targets are similar to receivers of information. The twelve-factor method that NLog can target can be used. The goals of File and Mail are additional. Target behaviors' are improved and modified by wrappers. For example, the AsyncWrapper boosts achievement by asynchronously sending logs. The target setup can be changed without changing the code or recompiling it by updating the NLog.config file.
NLog supports the following types of logging levels
- DEBUG: In addition, application usage details are required for situations where those details are required to identify issues.
- INFO: General-purpose application events
- WARN: Application events that might indicate a problem are flagged as WARN.
- ERROR: Generally logged in a try/catch block, an exception, and contextual information. A fatal mistake forces the cancellation of an application.
- TRACE: Used over-performance profiling for recording the beginning and departure of functions.
The log information is filtered using logging levels. Configuring an ordinary production environment to only log errors and fatalities is possible. The logging level can be raised to accommodate DEBUG and WARN events if issues arise.
Log4NET
The well-liked and potent Java logging framework, Log4J, was ported to Log4NET. Like NLog, Log4NET can be set up and configured, and like NLog, a file called configuration contains settings that control how Log4NET sends log data. If a file is changed, the configuration can be set to reload the settings
instinctively.
Log4NET uses appenders to transmit log information to a wide range of targets. Sending log data to various data targets can be set up to use multiple appenders. The verbiage, or quantity of information that results from entering level, can be set using appenders in conjunction with configuration. Except for having no built-in TRACE level, Log4NET encourages precisely the same number of logging levels as NLog.
Error Logging Modules and Handlers (ELMAH)
ELMAH was developed especially for ASP.NET applications. It has a dashboard that can be utilized for viewing errors and is reasonably simple to set up. Although ELMAH is widely recognized and has been around for a while, it does not follow the twelve-factor method. ELMAH records data into databases such as MySQL, SQL Server, Postgres, etc. This approach combines concerns about logging with concerns about log persistence. As we'll discuss briefly, storing log data in a relational database is not the best option.
What to log and how to log?
The application code is made more accessible by dividing log management from logging concerns. However, entering code must still be done by developers. A program can become much more feasible by using effective logging. For operations teams, poor logging can be a nightmare. Developers must be aware of the data they should log and employ patterns that can be applied uniformly throughout an application.
Levels of logging
Generally, the more you log in, the better off you'll be when issues arise. Although logging everything is helpful for troubleshooting, it may lead to problems with disk usage. It can be challenging to search through large logs. Logging levels are used for filtering logging output, adjusting the volume of data output to the circumstances at hand.
The category of data logged corresponds to each level of logging. Usually, non-error conditions, DEBUG, INFO, and TRACE incidents provide information about how an application behaves.
They are frequently turned on in environments other than production and turned off within real-world manufacturing settings, depending on how they're used. Error and warning levels are frequently allowed in manufacturing environments so that issues can be reported. Only crucial, urgent information that affects the accessibility of an application is logged during production as a result.
When using each logging level that a particular framework offers, developers benefit from some discretion. A standardized structure for what data is logged as well as what level should be established by development teams. While it might differ from one application to the next, it should be the same for all applications under one umbrella.
What are the Problems With Log Files?
If your application doesn't receive a lot of traffic, log files on your development machine are fantastic. When your application was finished being developed, did you ever need to interact with the log files? If so, you will soon encounter the following problems:
- More information is available.
- You must gain access to the information.
- It's dispersed among several servers.
- There could be multiple assistance boundaries for a single operation, meaning additional logs are needed to sift through.
- Even if you decide to include it in SQL, you will need to do a lot of indexing to make it useful because it is flat and difficult to query.
- Usually, you lack all the user context information.
- Perhaps missing from your explanation are some details that would be useful (you mean "log.Info('In the method')" isn't helpful?).
- In addition, despite all the valuable information regarding your app being generated, you aren't actively using it.
The Best Ways to Advance Logging
Logging communications (including exceptions) is typically the only choice once you've started working on an application outside of a development environment for quickly figuring out why something isn't working as it should. APM tools may alert you to memory breaches as well as performance bottlenecks. Still, they aren't sufficiently detailed to help you figure out why a particular issue occurs, such as why this individual can't log in or this record isn't processing.
The "way of logging" we've established aims to achieve the following four objectives:
- Basic logging around everything - Every key transaction in your code must include some basic logging, so you should do this around the entire perimeter of your code.
- Log contextual data – Record contextual data. Simply noting that "something happened" was not sufficient. Contextual, pertinent logs are required.
- Aggregate logs – Summarized logs Each of our logs should be gathered together in one place that is easily distillable and accessible to all developers.
- Proactively use logs – Proactively use logs- Check your logging for mistakes and other vital issues.
Structured versus contextual logging
Contextual and structured logging are the two types of logging that are supported in C#.
Data on the event context is provided by contextual logging, which usually includes data on timestamps, the message's origin, and log levels. Using contextual logging, users can comprehend the series of occurrences that lead to system errors or other problems
On the other hand, the use of a stated logging schema makes it easier for consumers to search for and evaluate data. Structured logging, on the other hand, is a contemporary method that offers an additional structured and effective way to log data. Each recorded message in structured logging has a set of characteristics that are used to filter and arrange the log data.
Conclusion
The feasibility of an application is significantly impacted by effective logging. It's critical to distinguish between issues related to logging and log storage. This division of concerns is offered by well-known logging frameworks for.NET. Additionally, they offer features that simplify filtering log data and log consistently.
Log aggregation tools, both free and paid, are crucial resources, mainly if there are a lot of applications logging a lot of data. The developers in your organization can create applications that your operations teams can support reasonably easily if they have the right tools and knowledge.
Although logging is an essential component of your development toolkit, it may be time-consuming and inaccurate if you need to find a solution quickly or much more rapid and precise debugging; logging should be used in addition to a malfunctioning reporting tool.