omit_norms: true PUT _mapping exception

[jpcarey]

When using the PUT _mapping api in 1.x builds (tested with 1.5.2, 1.6.0, 1.6.1, 1.6.2, 1.7.4. Does not repo with 2.1.1) and

{ "_default_": { "_all": { "enabled": true, "omit_norms": true } } }

is set (logstash template: logstash-plugins/logstash-output-elasticsearch@e4590a2); adding a mapping for a new field of an existing type will throw the following error:

{ "error": "MergeMappingException[Merge failed with failures {[mapper [_all] cannot enable norms (norms.enabled)]}]", "status": 400 }

Steps to reproduce:

PUT logstash-example

PUT logstash-example/_mapping/_default_
{
"_default_": {
  "_all": {
     "enabled": true,
     "omit_norms": true
  }
 }
}

PUT logstash-example/_mapping/syslog
{
   "syslog": {
  }
}

PUT logstash-example/_mapping/syslog
{
  "properties": {
    "tags": {
      "type": "string"
    }
  }
}

[clintongormley]

Hi @jpcarey

Yes, this is a bug which has been fixed by the great mapping rewrite (#8870) in 2.x. These changes are way too big to backport (and break bwc). As a workaround, specify the _all mapping again:

PUT logstash-example/_mapping/syslog
{
  "_all": {
    "enabled": true,
    "omit_norms": true
  },
  "properties": {
    "tags": {
      "type": "string"
    }
  }
}