How can ElasticSearch be used to implement social search?

Question

I’m trying to create a business search with social features using ElasticSearch. I have a business directory, and users can interact with those businesses in different ways: b

Answer 1

Solr can do this with the GraphQuery operator.

https://issues.apache.org/jira/browse/SOLR-7543

It allows you to put documents in your index that contain a field for the "node_id" and a (multivalued) field for the "edge_id"

There are a few ways to structure this:

1. You can have a user document with a list of friend ids on it. Or
2. You can have a separate table that is a link table that links between user records.

For case 1: Index a document for each user in the system with a field containing the "user_id" and another field containing "friend_ids".

At that point to do a search for all friends for user 555 would be:

{!graph from="user_id" to="friend_ids" maxDepth=1}user_id:555

To find friends of friends of the user

{!graph from="user_id" to="friend_ids" maxDepth=2}user_id:555

If you have other metadata fields on the user records such as a location field you could add that as a traversal filter to find my friends that live in Boston. This traversal filter is applied to each hop.

{!graph from="user_id" to="friend_ids" maxDepth=2 traversalFilter="location:Boston"}user_id:555

The above query would find the friends that live in Boston that are friends User 555's that live in Boston.