Just some food for thought:

In the DSL you give, there are some subtle issues which makes it hard for
implementing a parser and correct query execution.

For example, the word "New feature": is it just a phrase, or is it two
terms? Is a span query for the two terms also valid?

Another issue is well-formed input data typing. Is "ES" in the query an
input of type "string"? And is "3.1" is double value or also a string type?
Can types always be inferenced? What about date parsing, will date types be
assigned automatically? Maybe by looking up the ES mapping (well, ES
parsers do that already) ? Or, how to decide if "true" is the string "true"
or the boolean constant? ES catches this but I mean the general case of an
external DSL is dealing with JSON data type flaws. You are forced to
re-implement the ES parser for all these nasty pitfalls.

How to declare facets and filters in an external DSL? Or multi phrase and
multi wildcard searching? It's not straightforward if there is simply no
context information how to execute such things. How do you parse and
translate wildcards mixed/nested with phrases such as "scien* 'week*
magazin*'"? I was surprised how many folks are trained to use wildcards
excessively. It is only possible to replace such "bad queries" with
heuristics that can be executed on ES with high performance, with ranked
results etc.

I have written a CQL parser
http://docs.oasis-open.org/search-ws/searchRetrieve/v1.0/os/part5-cql/searchRetrieve-v1.0-os-part5-cql.pdfto
generate ES DSL, but for Java API only. If anyone is interested in
adding a CQL parser as a REST action, I could offer it as a plugin. It is
of course not perfect, I'm not very satisfied with the result.

My experience so far is, at least for CQL, because it is a weak typed query
language (it does not have a notion of input data types) , that external
query languages must really be able to match the power of Lucene/ES
features, or you get into trouble implementing simplifications, fallbacks,
and shortcuts all the way.

So my favorite is still ES DSL, and for establishing simple searches, there
are special featured query types that are designed for simplified free form
input. E.g. ES DSL query type "query_string" understands the Lucene syntax,
or the "match" query, and now we also have the "simple_query"
https://github.com/elasticsearch/elasticsearch/pull/4402

I'm interested in OpenSearch for ES http://www.opensearch.org/ so if anyone
is working on this, it would be nice to know.

Jörg


On Thu, Dec 19, 2013 at 8:05 PM, xin zhang <[email protected]> wrote:
>
>
> project = ES AND issuetype = "New Feature" AND fixVersion = 3.1 ORDER BY
> created DESC, cf[10514] DESC
>
>
>

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