Query Parser Plus Plus Plus

Query Parser Plus Plus Plus is a query_string alternative for Elasticsearch with a features:

• No syntax returns an error. Everything just devoles into a simpler query.
• Fields can be indexed many ways queries should be rewritten to take advantage of it. Wildcard searches automatically search in more precise fields and can even search in specially analyzed fields that allow the search to be rewritten as a term query.
• The user is allowed to specify different fields to search (just like query_string) but which fields they are allowed to specify is controlled by a whitelist.

Installation

TODO fix me I'm totally wrong

Extra Queries and Filters Plugin	ElasticSearch
master branch	1.5.X

Once its released you can install it like so for Elasticsearch 1.5.x:

./bin/plugin --install org.wikimedia.search/query_string_plus_plus_plus/0.0.1

But for now you have to build it yourself.

Options

            Option                |                    Purpose                    |                    Type                    | Default

--------------------------------------|-----------------------------------------------|--------------------------------------------|-------- query | The query text to translate. | string | Required fields.default or fields | The fields to query by default. | fields string | Required default_operator | The default operator for two terms next to eachother. | "and" or "or" | "and" empty | Query to use on an empty query string | "match_all" or "match_none" | "match_all" allow_leading_wildcard | Is it ok if wildcard queries start with a wildcard? | boolean | false regex | Enables and configures regex search. | object | null fields.whitelist_defaults | Should the fields in the fields.default parameter be automatically whitelisted? | boolean | true fields.whitelist_all | Should all not blacklisted fields be whitelisted? | boolean | false fields.whitelist | Fields that can be queried. | list of strings | [] fields.blacklist | Fields that can't be queried. | list of strings | [] fields.aliases | Aliases from one field name to one or more field names. | object with aliases as keys and fields string as values | {} fields.definitions | Defines what actual fields are searched when searching a field name. | object | {}

Note about fields.whitelist_defaults: The default fields will be queried even if they aren't whitelisted but if this is true (and it is by default) then users will be able to select all of these fields with the field:query syntax.

Note about the format of fields.default and the values in the fields.aliases object: The "fields string" is of the format: "field(^boost)?(, ?field(^boost)?)*".

Field resolution

Field resolution is a staged process:

1. Parse the reference including the boost
2. Expand aliases
3. Remove fields that don't pass the whitelist or blacklist
4. Resolve the field definitions for each field

The takeaway from this is that the whitelist/blacklist process comes after alias expansion and before field definition substitution. Whitelisting the "from" part of the alias does nothing, as does whitelisting the "quoted" or "unquoted" parts of the field definitions.