To configure logging in self-hosted Ory Kratos so that logs are formatted as JSON and stack traces are grouped into a single message, you should: 1. Set the log format to json. 2. Set the log level to trace if you want stack traces included in log messages. 3. You can do this either via environment variables or in your configuration file. Example using environment variables:

LOG_LEVEL=trace LOG_FORMAT=json

Example in your configuration file (YAML):

yaml log:   level: trace   format: json   leak_sensitive_values: false

With

LOG_LEVEL=trace

, traces (including stack traces) will be included for log calls and errors, and when using

json

as the format, the stack trace will be grouped into a single JSON message under the "trace" key. This ensures the stack trace is not split across multiple log lines, making it easier to parse and analyze programmatically [Logs and audit trails](https://www.ory.sh/docs/self-hosted/operations/logging). Example log output:

json {   "audience": "application",   "error": {     "message": "example error",     "trace": "stack trace here"   },   "level": "error",   "msg": "I am an example error",   "service_name": "foo",   "service_version": "bar",   "time": "2020-05-20T12:13:53+02:00" }

This configuration will give you JSON-formatted logs with stack traces grouped in a single message.

I'm sorry, but the knowledge sources do not contain information about customizing the logging format specifically for Fluent Bit in Ory Kratos. The documentation only covers configuring the log format to either text or JSON, and setting log levels, but does not mention Fluent Bit or provide guidance on integration or customization for it [Logs and audit trails](https://www.ory.sh/docs/self-hosted/operations/logging). If you need to integrate with Fluent Bit, you may consider using the JSON log format, as Fluent Bit can easily parse JSON logs, but for further customization, please refer to Fluent Bit's own documentation or community resources.