Trace Analytics, a new capability in Open Distro for Elasticsearch

Can anyone explain the data flow for this sample application provided - the trace-analytics-sample-app

We have the following 6 services that docker compose brings up:

#1 data-prepper:
image

#2 opendistro-for-elasticsearch

#3 Kibana

#4 otel-collector

vendor-agnostic way to receive, process and export telemetry data

#5 mysql

#6 sample-app
ports:

  - '8082:8082' # inventory

  - '8083:8083' # database

  - '8084:8084' # payment

  - '8085:8085' # auth

  - '8086:8086' # recommendation

  - '8087:8087' # analytics-service

  - '8088:8088' # order

  - '8089:8089' # client-dashboard

How is data passed to the data-prepper and the otel-collector from the python code that is provided in the sample-app directory?