Add a summary of IngestStats to ClusterStatsNodes

[talevy]

It would be nice to see a unified view of which processors are being used by the cluster in the cluster-stats response. Right now, ingest-stats is present in node stats, but it is left out of cluster-stats. This issue is open to discuss and track if and how it makes sense to expose these details in the ClusterStatsNodes part of the ClusterStatsResponse

Some information that would be interesting to provide that is missing

• number of pipelines present
• set of processor types used

[elasticmachine]

Pinging @elastic/es-core-features

[talevy]

Come to think of it, this type of info may be better served in the Cluster Info Response

For example

    "ingest" : {
      "number_of_pipelines" : 2,
      "processor_types" : [
        "circle",
        "gsub",
        "script"
      ]
    }

Can you think of any other information you'd like to see in this @giladgal?

[giladgal]

To document our quick discussion about it, we want to collect:

1. Which environments used the processor
2. How many records were ingested by the processor

[martijnvg]

👍 I think we can easily include this information (all installed processor types with a node count and the cluster wide ingest count) in the cluster stats api when it gathers stats from all nodes that are part of the cluster.