Elastic Stack Lab08

In this lab you will be creating a new index, new mappings, and relationships between the data in our Elasticsearch cluster.

Create new mapping

Sometimes you have data that is related. In this example we are going to create a parent/child relationship between films and the franchise they are part of.

curl -XPUT 127.0.0.1:9200/series -d '
{
    "mappings" : {
        "movie": {
            "properties": {
                "film_to_franchise": {"type": "join", "relations": {"franchise" : "film"}}
            }
        }
    }
}'

Notice we created new properties with a field film_to_franchise and a new type of join then we are saying franchise and film values are related.

Query new series data

Now that we have created the new index and mapping we need to populate it with data.

Download the file containing the series information.

wget http://bit.ly/es-series-data -O series.json

We review the contents of this file in class, but if you want to look through it again feel free.

Now we are going to import this new data into our series index.

curl -XPUT 127.0.0.1:9200/_bulk?pretty --data-binary @series.json

Confirm there were no errors in the output.

Let’s run a query now to find all of the films that are part of the Star Wars franchise!

To do this we are going to use the has_parent option with a parent_type of franchise. This should return all of the documents in our series index that are children of the franchise.

curl -XGET 127.0.0.1:9200/series/movie/_search?pretty -d '
{
    "query" : {
        "has_parent": {"parent_type": "franchise", "query": { "match" : {"title": "Star Wars"}}}
    }
}'

What did you get back?

Now let’s try to find the parent for a specific child.

curl -XGET 127.0.0.1:9200/series/movie/_search?pretty -d '
{
    "query" : {
        "has_child": {
            "type": "film", "query": {"match": {"title": "The Force Awakens"}}
        }
    }
}'

Did it return the correct results?

Remember that indexing parent/child joins can take a lot of performance, also need to make sure you index them specifically to the same shard. So this can be a complicated, expensive design and you should only do it if absolutely necessary.

Extra credit

* Import any other movie, that isn’t Star Wars, into the `series` index 
* Perform a search to show all movies in the `series` index. 
* Query for all movies in the “Star Wars” franchise and confirm your movie does not show up.

Lab Complete