Using Ingest node Enrich your data with "multiple" match fields

[cho]

Hey there.

I've been experimenting with the newly added data enrichment funtions in ES 7.5 and came up with the following problem.

Let's pretend we have those indices:

article_to_group

{
  "article_key": 123456,
  "article_group": "foobars"
}

article_views_from_other_data_source

{
  "date": "2019-12-10",
  "article_group": "foobars",
  "other_views": 1440
}

Building the enrichtment process

I came up with the following so far:

PUT /_enrich/policy/group_policy
{
    "match": {
        "indices": [
            "article_to_group"
        ],
        "match_field": "article_key",
        "enrich_fields": ["article_group"]
    }
}
POST /_enrich/policy/group_policy/_execute

PUT /_enrich/policy/other_views_policy
{
    "match": {
        "indices": [
            "article_views_from_other_data_source"
        ],
        "match_field": "article_group",
        "enrich_fields": ["other_views"]
    }
}
POST /_enrich/policy/other_views_policy/_execute

// Create pipeline
PUT /_ingest/pipeline/views_lookup
{
  "description" : "Enriching...",
  "processors" : [
    {
        "enrich" : {
          "policy_name": "group_policy",
          "field" : "article_key",
          "target_field": "info",
          "max_matches": "1"
        }
    },
    {
      "enrich" : {
        "policy_name": "other_views_policy",
        "field" : "info.article_group",
        "target_field": "other_views",
        "max_matches": "1"
      }
    }
  ]
}

Execute our pipeline

POST /my_test_index/_doc/1?pipeline=views_lookup
{
  "article_key": 123456,
  "views": 1337
}

Result of GET /my_test_index/_doc/1 is

{
    "other_views" : {
      "other_views" : 1440,
      "article_group" : "foobars"
    },
    "article_key" : 123456,
    "views" : 1337,
    "info" : {
      "article_key" : 123456,
      "article_group" : "foobars"
    }
}

Unfortunately this won't work as soon as there are mutiple logs in the article_views_from_other_data_source with the same article_group, but different dates.

Is there a way to define date as a "second" match_field in the pipeline definition with the query field?