Wildcard search support

[szakitibi]

Current version of EZCTextIndex does not support wildcard search.

To be exact it strips * wildcard from the end of the search value:

        # ES doesn't care about * like zope catalog does
        clean_value = value.strip('*') if value else ""

The * wildcard is added by Plone global search, thus current version changes how global search works!

ElasticSearch supports wildcard query since version 0.90.

Suggestion:

At the end of the EZCTextIndex.get_query method:

    if clean_value != value:
        # ES docs says:
        #     "to prevent extremely slow wildcard queries, a wildcard
        #      term should not start with one of the wildcards * or ?"
        # strip all wildcards from left and remove excess spaces
        stripped_value = ' '.join([i.lstrip('*?') for i in value.split()]).strip()
        # if we still have a valid value, append as wildcard query
        if stripped_value:
            queries.append({"wildcard": {name: stripped_value}})

Note: It would still change Plone global search. It supports both ? and * wildcard characters, but in my opinion adding extra functionality to global search is still better then stripping it away.