Add support for full text search

[flimzy]

CouchDB 3.0.0 adds (optional) full-text support through the _search endpoint. Support should be added for this, and the related _search_analyze endpoint.

• https://docs.couchdb.org/en/stable/api/ddoc/search.html
• https://docs.couchdb.org/en/stable/api/ddoc/search.html#db-design-design-doc-search-info-index-name
• https://docs.couchdb.org/en/stable/api/server/common.html#search-analyze

[flimzy]

The following endpoints were added:

• GET /{db}/_design/{ddoc}/_search/{index}
• GET /{db}/_design/{ddoc}/_search_info/{index}
• POST /_search_analyze

[flimzy]

I think I can add three methods to satisfy this new API:

• Search(), the analog to Query() and Find(), will be used to perform search queries.
• SearchInfo() will be used for the _search_info endpoint
• SearchAnalyze will be the analog to Explain for mango queries.

[flimzy]

Testing this functionality is non-trivial, as starting the Lucene plugin is not currently possible with standard Docker. For now I'm putting this on hold until it is easier to test, or there is a pressing need for it, to serve as motivation to device an alternate testing method.

[rossmerr]

Hey I got this working in docker following the guide at apache/couchdb-docker#8 (comment)

so can we add this back in?

[flimzy]

Thanks for the heads-up, @rossmerr! That's very promising, and full text search is something I'm likely to need at work soon, so I'll see about getting around to working on this feature when time permits (and a PR is course welcome if someone else has time before I get to it).