How to query and list all types within an elasticsearch index?

Question

Problem: What is the most correct way to simply query for and list all types within a specific index (and all indices) in elasticsearch?

I've been reading through the reference and API but can't seem to find anything obvious.

I can list indices with the command:

$ curl 'localhost:9200/_cat/indices?v'

I can get stats (which don't seem to include types) with the command:

$ curl localhost:9200/_stats

I'd expect that there'd be a straightforward command as simple as:

$ curl localhost:9200/_types

or

$ curl localhost:9200/index_name/_types

Thanks for any help you can offer.

Answer 1

What you call "type" is actually a "mapping type" and the way to get them is simply by using:

curl -XGET localhost:9200/_all/_mapping

Now since you only want the names of the mapping types, you don't need to install anything, as you can use simply use Python to only get you what you want out of that previous response:

curl -XGET localhost:9205/_all/_mapping | python -c 'import json,sys; indices=json.load(sys.stdin); indices = [type for index in indices for type in indices.get(index).get("mappings")]; print list(indices);'

The Python script does something very simple, i.e. it iterates over all the indices and mapping types and only retrieves the latter's names:

import json,sys; 
resp = json.load(sys.stdin); 
indices = [type for index in resp for type in indices.get(index).get("mappings")]; 
print list(indices);'

UPDATE

Since you're using Ruby, the same trick is available by using Ruby code:

curl -XGET localhost:9205/_all/_mapping | ruby -e "require 'rubygems'; require 'json'; resp = JSON.parse(STDIN.read); resp.each { |index, indexSpec | indexSpec['mappings'].each {|type, fields| puts type} }"

The Ruby script looks like this:

require 'rubygems';
require 'json';
resp = JSON.parse(STDIN.read);
resp.each { |index, indexSpec | 
    indexSpec['mappings'].each { |type, fields| 
        puts type
    }
}

Answer 2

You can just print the index and use the _mapping API so you will see only the section of "mappings" in the index.

For example: curl -GET http://localhost:9200/YourIndexName/_mapping?pretty

You will get something like that:

{
"YourIndexName" : {
    "mappings" : {
      "mapping_type_name_1" : {
        "properties" : {
          "dateTime" : {
            "type" : "date"
          },
          "diskMaxUsedPct" : {
            "type" : "integer"
          },
          "hostName" : {
            "type" : "keyword"
          },
          "load" : {
            "type" : "float"
          },
          "memUsedPct" : {
            "type" : "float"
          },
          "netKb" : {
            "type" : "long"
          }
        }
      },
      "mapping_type_name_2" : {
        "properties" : {
          "dateTime" : {
            "type" : "date"
          },
          "diskMaxUsedPct" : {
            "type" : "integer"
          },
          "hostName" : {
            "type" : "keyword"
          },
          "load" : {
            "type" : "float"
          },
          "memUsedPct" : {
            "type" : "float"
          }
        }
      }
    }
  }
}

mapping_type_name_1 and mapping_type_name_2 are the types in this index, and you also can see the structure of these types.

Good explanation about mapping_types is here: https://logz.io/blog/elasticsearch-mapping/