Preface

In the previous article, we talked about AspNetCore Application of multi environment configuration file , We configure multiple according to our various environments appsettings.$EnvironmentName.json file .
In actual development, we may encounter more than one configuration file , Such as when we use log4net Log library error , Prefer to use separate log4net.config The configuration file . And we also encounter... In different environments log4net There are also differences in the configuration file . At this time, we may be able to follow appsettings.json The style of multi environment configuration realizes multi environment configuration file .

To configure log4net

newly build Web project

install Microsoft.Extensions.Logging.Log4Net.AspNetCore

Create two environment configuration files, as shown in Figure , And set the file properties so that it can be copied to the root directory when publishing

The contents of the two configuration files are as follows , For example, we add one more to the configuration file of the production environment KafkaAppender Send logs to kafka The message is lost in the column , then kafka Of consumers consume logs to ES colony , However, there is no need to upload locally developed logs ES.

<!--log4net.config-->
<?xml version="1.0" encoding="utf-8" ?>
<log4net>
  <!-- If you are looking here and want more output, first thing to do is change root/priority/@value to "INFO" or "ALL". -->
  <root>
    Value of priority may be ALL, DEBUG, INFO, WARN, ERROR, FATAL, OFF.
    <priority value="ALL" />
    <appender-ref ref="error-file" />
    <appender-ref ref="debug-file" />
    <appender-ref ref="KafkaAppender" />
  </root>

  <!-- Example of turning on the output from a component or namespace. -->
  <logger name="Common">
    <appender-ref ref="debugger"/>
    <priority value="DEBUG" />
  </logger>
  
  <appender name="KafkaAppender" type="log4net.Kafka.Appender.KafkaAppender, log4net.Kafka.Appender">
    <KafkaSettings>
      <brokers>
        <add value="127.0.0.1:9092" />
      </brokers>
      <topic type="log4net.Layout.PatternLayout">
        <conversionPattern value="kafka.logstash" />
      </topic>
    </KafkaSettings>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date %level% [%t] %logger - %message" />
    </layout>
  </appender>
  
  <appender name="debugger" type="log4net.Appender.DebugAppender">
    <!-- Sends log messages to Visual Studio if attached. -->
    <immediateFlush value="true" />
    <layout type="log4net.Layout.SimpleLayout" />
  </appender>

  <appender name="debug-file" type="log4net.Appender.RollingFileAppender">
    <param name="Encoding" value="utf-8" />
    <file value="Logs/debug" />
    <appendToFile value="true" />
    <!-- Immediate flush on error log, to avoid data loss with sudden termination. -->
    <immediateFlush value="true" />
    <staticLogFileName value="false" />
    <rollingStyle value="Date" />
    <datepattern value="-yyyy.MM.dd'.log'" />
    <!-- Prevents Orchard.exe from displaying locking debug messages. -->
    <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date %level% [%property{trace}] %logger - %message%newline" />
    </layout>
  </appender>

  <appender name="error-file" type="log4net.Appender.RollingFileAppender">
    <param name="Encoding" value="utf-8" />
    <file value="Logs/error" />
    <appendToFile value="true" />
    <!-- Immediate flush on error log, to avoid data loss with sudden termination. -->
    <immediateFlush value="true" />
    <staticLogFileName value="false" />
    <rollingStyle value="Date" />
    <datepattern value="-yyyy.MM.dd'.log'" />
    <!-- Prevents Orchard.exe from displaying locking debug messages. -->
    <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
    <filter type="log4net.Filter.LevelRangeFilter">
      <!-- Only ERROR and FATAL log messages end up in this target, even if child loggers accept lower priority. -->
      <levelMin value="ERROR" />
    </filter>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%t] %logger - %message [%P{Url}]%newline" />
    </layout>
  </appender>

</log4net>

<!--log4net.Development.config-->
<?xml version="1.0" encoding="utf-8" ?>
<log4net>
  <!-- If you are looking here and want more output, first thing to do is change root/priority/@value to "INFO" or "ALL". -->
  <root>
    Value of priority may be ALL, DEBUG, INFO, WARN, ERROR, FATAL, OFF.
    <priority value="ALL" />
    <appender-ref ref="error-file" />
    <appender-ref ref="debug-file" />
  </root>

  <!-- Example of turning on the output from a component or namespace. -->
  <logger name="Common">
    <appender-ref ref="debugger"/>
    <priority value="DEBUG" />
  </logger>
  
  <appender name="debugger" type="log4net.Appender.DebugAppender">
    <!-- Sends log messages to Visual Studio if attached. -->
    <immediateFlush value="true" />
    <layout type="log4net.Layout.SimpleLayout" />
  </appender>

  <appender name="debug-file" type="log4net.Appender.RollingFileAppender">
    <param name="Encoding" value="utf-8" />
    <file value="Logs/debug" />
    <appendToFile value="true" />
    <!-- Immediate flush on error log, to avoid data loss with sudden termination. -->
    <immediateFlush value="true" />
    <staticLogFileName value="false" />
    <rollingStyle value="Date" />
    <datepattern value="-yyyy.MM.dd'.log'" />
    <!-- Prevents Orchard.exe from displaying locking debug messages. -->
    <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date %level% [%property{trace}] %logger - %message%newline" />
    </layout>
  </appender>

  <appender name="error-file" type="log4net.Appender.RollingFileAppender">
    <param name="Encoding" value="utf-8" />
    <file value="Logs/error" />
    <appendToFile value="true" />
    <!-- Immediate flush on error log, to avoid data loss with sudden termination. -->
    <immediateFlush value="true" />
    <staticLogFileName value="false" />
    <rollingStyle value="Date" />
    <datepattern value="-yyyy.MM.dd'.log'" />
    <!-- Prevents Orchard.exe from displaying locking debug messages. -->
    <lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
    <filter type="log4net.Filter.LevelRangeFilter">
      <!-- Only ERROR and FATAL log messages end up in this target, even if child loggers accept lower priority. -->
      <levelMin value="ERROR" />
    </filter>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%t] %logger - %message [%P{Url}]%newline" />
    </layout>
  </appender>

</log4net>

stay Program.cs Add log4net The configuration is as follows

// =============== Multiple environments log4net To configure ===============
IWebHostEnvironment environment = builder.Environment;
var configName = "log4net" + (environment.IsProduction() ? string.Empty : "." + environment.EnvironmentName) + ".config";
builder.Logging.AddLog4Net(configName, watch: true);
// =============== Multiple environments log4net To configure ===============

Now all the configuration is complete .