Nlog: Not work FallbackGroup

[carkov1990]

Type : Bug

NLog version: 4.5.0-rc07

Platform: .NET Core 2.0

Hi! I created .net core console app. Added NuGet packages NLog

<PackageReference Include="NLog" Version="4.5.0-rc07" />
<PackageReference Include="NLog.Targets.ElasticSearch" Version="4.0.0-beta26" />

and config

<nlog autoReload="false" throwExceptions="true" internalLogFile="d:/0_logs/NLog.log" internalLogLevel="Warn" xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <extensions>
        <add assembly="NLog.Targets.ElasticSearch" />
    </extensions>
<variable name="logDirectory" value="${basedir}/logs/${shortdate}" />
    <variable name="typeVariable" value="" />
    <targets>
        <target name="BufferingWrapper" xsi:type="BufferingWrapper" bufferSize="1">
            <target name="FallbackFromElasticToFile" xsi:type="FallbackGroup" returnToFirstOnSuccess="true">
                <target name="ElasticSearch" xsi:type="ElasticSearch" uri="http://host:9200/" index="logs-${shortdate}" documentType="${typeVariable}" includeAllProperties="true" disableAutomaticProxyDetection="true" layout="${message}">
                    <field name="host" layout="${machinename}" layoutType="System.String" />
                    <field name="environment" layout="${env}" layoutType="System.String" />
                    <field name="processid" layout="${processid}" layoutType="System.Int32" />
                    <field name="threadid" layout="${threadid}" layoutType="System.Int32" />
                    <field name="logger" layout="${logger}" layoutType="System.String" />
                </target>
                <target name="File" xsi:type="File" fileName="${logDirectory}\${logger}.${machinename}.log" createDirs="true" keepFileOpen="false" encoding="utf-8" layout="${longdate} | [${level:uppercase=true}] ${message} ${all-event-properties} ${onexception:inner=${newline}${exception:format=ToString,StackTrace}${newline}}">
                </target>
            </target>
        </target>
    </targets>
    <rules>
        <logger name="*" writeTo="BufferingWrapper" minlevel="Trace" />
    </rules>
</nlog>

Application should write log every seconds, but it not work.
I changed config and my app started working. I just deleted FallbackGroup.
Worked config:
xml <nlog autoReload="false" throwExceptions="true" internalLogFile="d:/0_logs/NLog.log" internalLogLevel="Warn" xmlns="http://www.nlog-project.org/schemas/NLog.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <extensions> <add assembly="NLog.Targets.ElasticSearch" /> </extensions> <variable name="logDirectory" value="${basedir}/logs/${shortdate}" /> <variable name="typeVariable" value="" /> <targets> <target name="BufferingWrapper" xsi:type="BufferingWrapper" bufferSize="1"> <target name="ElasticSearch" xsi:type="ElasticSearch" uri="http://cg-esd.kad.local:9200/" index="logs-datalake-${shortdate}" documentType="${typeVariable}" includeAllProperties="true" disableAutomaticProxyDetection="true" layout="${message}"> <field name="host" layout="${machinename}" layoutType="System.String" /> <field name="environment" layout="${env}" layoutType="System.String" /> <field name="processid" layout="${processid}" layoutType="System.Int32" /> <field name="threadid" layout="${threadid}" layoutType="System.Int32" /> <field name="logger" layout="${logger}" layoutType="System.String" /> </target> </target> </targets> <rules> <logger name="*" writeTo="BufferingWrapper" minlevel="Trace" /> </rules> </nlog>

• What is the current result?
  Not write to Elastic every second
• What is the expected result?
  Write log every second
• Did you checked the Internal log?
  Yes, I checked. Internal log:
  In internal log:
  Trace BufferingWrapper 'BufferingWrapper': writing 1 events (Exceeding BufferSize)

Why FallbackGroup not work in .net core 2.0? It is my mistake or bug in NLog?

[snakefoot]

You are probably been affected by the following bug: https://github.com/ReactiveMarkets/NLog.Targets.ElasticSearch/issues/53 (You should add comment that you are also affected).

Maybe a workaround could be this:

<target name="FallbackFromElasticToFile" xsi:type="FallbackGroup" returnToFirstOnSuccess="true">
    <target name="ElasticSearchAsync" xsi:type="AsyncWrapper" timeToSleepBetweenBatches="0" overflowAction="Block" batchSize="10">
        <target name="ElasticSearch" xsi:type="ElasticSearch" uri="http://host:9200/" index="logs-${shortdate}" documentType="${typeVariable}" includeAllProperties="true" disableAutomaticProxyDetection="true" layout="${message}">
                    <field name="host" layout="${machinename}" layoutType="System.String" />
                    <field name="environment" layout="${env}" layoutType="System.String" />
                    <field name="processid" layout="${processid}" layoutType="System.Int32" />
                    <field name="threadid" layout="${threadid}" layoutType="System.Int32" />
                    <field name="logger" layout="${logger}" layoutType="System.String" />
        </target>
    </target>
    <target name="File" xsi:type="File" fileName="${logDirectory}\${logger}.${machinename}.log" createDirs="true" keepFileOpen="false" encoding="utf-8" layout="${longdate} | [${level:uppercase=true}] ${message} ${all-event-properties} ${onexception:inner=${newline}${exception:format=ToString,StackTrace}${newline}}">
    </target>
</target>

Remember to update the logging rule to use FallbackFromElasticToFile (instead of BufferingWrapper)

[carkov1990]

Thank you! Workaround worked for me. Maybe my app really been affected that bug.

[304NotModified]

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