Hey Folks, I'd love some feedback on the interface for nested document faceting (or rather switching facet domains to/from parent/child).
See the bottom of this blog: http://yonik.com/solr-nested-objects/ Issue #1: How to specify that one should change domains before faceting? I originally started out with a new facet type (like query facet, but switches domains). So if you started out querying a child of type book, you would first do a "blockParent" facet to map the domain to parents, and then put the actual facet you wanted as a sub-facet. q=book_review:xxxxxx /* query some child-doc of book */ json.facet= { // NOTE: this was my first pass... not the current interface books : { type: blockParent, parentFilter : "type:book" facet : { authors : { type : terms, field : author } } } Although having a separate facet type to map domains is logically very clean, it does introduce an additional level of indentation which may not be desired. So then I thought about including domain switching operations under a "domain" directive in the facet itself: json.facet= { // current form a domain switching facet authors : { type: terms, field: author, domain : {blockParent:"type:book"} } } I envision some future other options for "domain" including the ability to reset the domain with another query (ignoring your parent domain), or adding additional filters to the domain before faceting, or normal (non-block) joins. Issue #2: Naming I avoided toParent and toChild because people cloud be confused that it would work on any sort of parent/child relationship (i.e. other than nested documents). I used "blockParent" and "blockChildren" because I was thinking about block join. One alternative that might be better could be "nested" (i.e. nestedParent). Pluralization: I picked the singular for blockParent and plural for blockChildren since a single block as one parent and multiple children. But you could think about it in other ways since we're mapping a set of documents at a time (i.e. both could be pluralized). Options: nestedParent, nestedChildren // current option nestedParents, nestedChildren // both plural nestedChild, nestedParent // both singular Feedback appreciated! -Yonik
