For the geo, host, and hbaseEnrichment, this is sufficient. However, more complex enrichments might contain their own configuration. Currently, the stellar enrichment is more adaptable and thus requires a more nuanced configuration.

At its most basic, we want to take a message and apply a couple of enrichments, such as converting the hostname field to lowercase. We do this by specifying the transformation inside of the config for the stellar fieldMap. There are two syntaxes that are supported, specifying the transformations as a map with the key as the field and the value the stellar expression:

"fieldMap": {
       ...
      "stellar" : {
        "config" : {
          "hostname" : "To_LOWER(hostname)"
        }
      }
    }

Another approach is to make the transformations as a list with the same var := expr syntax as is used in the Stellar REPL, such as:

"fieldMap": {
       ...
      "stellar" : {
        "config" : [
          "hostname := TO_LOWER(hostname)"
        ]
      }
    }

Sometimes arbitrary stellar enrichments may take enough time that you would prefer to split some of them into groups and execute the groups of stellar enrichments in parallel. Take, for instance, if you wanted to do an HBase enrichment and a profiler call which were independent of one another. This use case is supported by splitting the enrichments up as groups.

For example:

 "fieldMap": {
       ...
      "stellar" : {
        "config" : {
          "malicious_domain_enrichment" : {
            "is_bad_domain" : "ENRICHMENT_EXISTS('malicious_domains', ip_dst_addr, 'enrichments', 'cf')"
          },
          "login_profile" : [
            "profile_window := PROFILE_WINDOW('from 6 months ago')", 
            "global_login_profile := PROFILE_GET('distinct_login_attempts', 'global', profile_window)",
            "stats := STATS_MERGE(global_login_profile)",
            "auth_attempts_median := STATS_PERCENTILE(stats, 0.5)", 
            "auth_attempts_sd := STATS_SD(stats)",
            "profile_window := null", 
            "global_login_profile := null", 
            "stats := null"
          ]
        }
      }
    }

Here we want to perform two enrichments that hit HBase and we would rather not run in sequence. These enrichments are entirely independent of one another (i.e. neither relies on the output of the other). In this case, we've created a group called malicious_domain_enrichment to inquire about whether the destination address exists in the HBase enrichment table in the malicious_domains enrichment type. This is a simple enrichment, so we can express the enrichment group as a map with the new field is_bad_domain being a key and the stellar expression associated with that operation being the associated value.

In contrast, the stellar enrichment group login_profile is interacting with the profiler, has multiple temporary expressions (for example, profile_window, global_login_profile, and stats) that are useful only within the context of this group of stellar expressions. In this case, we would need to ensure that we use the list construct when specifying the group and remember to set the temporary variables to null so they are not passed along.

In general, things to note from this section are as follows: