The Couchbase Plug-in for Elasticsearch has several settings in a YAML file that you can update. In the beginning you will probably only update the username and password for the plug-in. Later you may want to change these additional settings:
couchbase.port: the port the plug-in will listen on. Default is 9091.
couchbase.username: the username for HTTP basic authentication. Default is Administrator.
couchbase.password: the password for HTTP basic authentication. No default established.
couchbase.defaultDocumentType: the type of documents stored
in Elasticsearch. These documents contain indexing
information from Elasticsearch. Defaults to
couchbaseDocument. You can change this if
you define and implement your own document type which
provides specialized Elasticsearch search features. For more
information, see
Elasticsearch Guide, Index API
couchbase.checkpointDocumentType: type of document which
stores status information about replication. Default is
couchbaseCheckpoint.
couchbase.num_vbuckets: number of data partitions Elasticsearch should specify to Couchbase Server. Default corresponds to the number of partitions expected by Couchbase Server and that exist on the source Couchbase cluster. For Mac OSX, the value is 64, and for all other platforms it is 1024.
Understanding Metadata
As you get more advanced in your usage of Couchbase Plug-in for Elasticsearch, it might be helpful for you to understand what is actually sent via the plug-in and how Elasticsearch uses it. When you send a JSON document to Couchbase Server to store, it looks similar to the following:
{ "name": "Green Monsta Ale", "abv": 7.3, "ibu": 0, "srm": 0, "upc": 0, "type": "beer", "brewery_id": "wachusetts_brewing_company", "updated": "2010-07-22 20:00:20", "description": "A BIG PALE ALE with an awsome balance of Belgian malts with Fuggles and East Kent Golding hops.", "style": "American-Style Strong Pale Ale", "category": "North American Ale" }
Here we have a JSON document with all the information for a beer in our application. When Couchbase stores this document, it adds metadata about the document so that we now have JSON in Couchbase that looks like this:
{ { "id": "wachusetts_brewing_company-green_monsta_ale", "rev": "1-00000005ce01e6210000000000000000", "expiration": 0, "flags": 0, "type": "json" } { "name": "Green Monsta Ale", "abv": 7.3, "ibu": 0, "srm": 0, "upc": 0, "type": "beer", "brewery_id": "wachusetts_brewing_company", "updated": "2010-07-22 20:00:20", "description": "A BIG PALE ALE with an awsome balance of Belgian malts with Fuggles and East Kent Golding hops.", "style": "American-Style Strong Pale Ale", "category": "North American Ale" } }
The metadata that Couchbase Server stores with our beer document contains the key for the document, an internal revision number, expiration, flags and the type of document. When Couchbase Server replicates data to Elasticsearch via the plug-in, it sends this entire JSON including the metadata. Elasticsearch will then index the document and will store the following JSON with document metadata:
{ "id": "wachusetts_brewing_company-green_monsta_ale", "rev": "1-00000005ce01e6210000000000000000", "expiration": 0, "flags": 0, "type": "json" }
And finally when you query Elasticsearch and get a result set, it will contain the document metadata only:
{ took: 22 timed_out: false _shards: { total: 5 successful: 5 failed: 0 }, hits: { total: 1 max_score: 0.18642133 hits: [ { _index: beer-sample _type: couchbaseDocument _id: wachusetts_brewing_company-green_monsta_ale _score: 0.18642133 _source: { meta: { id: wachusetts_brewing_company-green_monsta_ale rev: 1-00000005ce01e6210000000000000000 flags: 0 expiration: 0 } } } ] } }