SAP Logging Connector

Introduction

The SAP Logging connector allows a Mendix app to output logs in a format supported by the Kibana dashboard provided by the SAP Business Technology Platform Application Logging service. Without this connector, logs sent to Kibana will not have the correct structure and log level.

By using this connector, logs will be output in a JSON format with the following fields:

• msg – the actual log message
• level – the log level
• written_at – the log timestamp as reported by the Mendix app
• written_ts – the log timestamp which can be used for ordering the logs
• stacktrace – the stack trace attached to the log message (if it exists)

In addition, the Connector supports multiline log messages.

Getting the SAP Logging Connector

To use the SAP Logging connector, you need to import it into your app from the Marketplace. For more information on importing modules from the Marketplace, see How to Use Marketplace Content.

Using the Connector

To format all the log messages, the SAP Logging Connector needs to be initialized during the startup of the Mendix application^[1].

To initialize the connector, do the following:

1. Open App > Settings in the App Explorer.

2. Switch to the Runtime tab.

3. Go to the After startup microflow by clicking Show next to the After startup microflow:

   

   If there’s no existing microflow (as indicated by the text (none), instead of a microflow name), click Select… and create a new microflow by clicking New:
   

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       <img src="/attachments/appstore/platform-supported-content/modules/sap-logger/logger_project_runtime_nostartup.png"
            alt="Runtime no After Startup" class="no-border"/> 
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4. In the App Explorer, drag and drop the RegisterSubscriber action from the SapApplicationLogs > USE_ME folder at the end of the After startup microflow:

   

5. Double-click the RegisterSubscriber action make sure that Log level is set to the constant SapLogLevel:

   

6. Edit the constant SapLogLevel to select the minimum log level which you want to send to the SAP Business Technology Platform Application Logging service. The supported log levels (case-insensitive) are Debug, Trace, Info, Warning, Error, and Critical.

   

Now, when the application is started, it will produce logs in the JSON format supported by Kibana.

Notes

• Due to technical limitations, the SAP Logging Connector is activated with a 5 second delay. This means that logging configuration is updated after the RegisterSubscriber action is completed.
• The RegisterSubscriber action checks to see if the Mendix application is running in an SAP environment with the SAP Business Technology Platform Application Logging service. If the SAP Business Technology Platform Application Logging service cannot be found, RegisterSubscriber assumes that the app is running locally and doesn’t change the logging configuration.
• When log messages are generated rapidly, it is possible that Kibana will display them in the wrong order. The written_at field can be used to sort the log messages.