I have general questions about the ingest feature in elasticsearch.
My need is to add several informations to the documents I index. Those informations are taken from external services reachable through REST APIs. I need to call many services, each of them will add one or more fields to my document. Each services can take a long time to execute.
I wanted to know if ingest feature is designed for performing such a long process.
Does the ingest pipeline execution is blocking or is it done in background ?
Can I write a custom ingest processor plugin that will perform the call to a REST API ?