apoc.nlp.gcp.classify.stream

Procedure Apoc Extended

Classifies a document into categories.

Signature

apoc.nlp.gcp.classify.stream(source :: ANY?, config = {} :: MAP?) :: (node :: NODE?, value :: MAP?, error :: MAP?)

Input parameters

Name Type Default

source

ANY?

null

config

MAP?

{}

Output parameters

Name Type

node

NODE?

value

MAP?

error

MAP?

Install Dependencies

The NLP procedures have dependencies on Kotlin and client libraries that are not included in the APOC Extended library.

These dependencies are included in apoc-nlp-dependencies-5.21.0-all.jar, which can be downloaded from the releases page. Once that file is downloaded, it should be placed in the plugins directory and the Neo4j Server restarted.

Setting up API Key

We can generate an API Key that has access to the Cloud Natural Language API by going to console.cloud.google.com/apis/credentials. Once we’ve created a key, we can populate and execute the following command to create a parameter that contains these details.

The following defines the apiKey parameter
:param apiKey => ("<api-key-here>")

Alternatively we can add these credentials to apoc.conf and load them using the static value storage functions.

apoc.conf
apoc.static.gcp.apiKey=<api-key-here>
The following retrieves GCP credentials from apoc.conf
RETURN apoc.static.getAll("gcp") AS gcp;
Table 1. Results
gcp

{apiKey: "<api-key-here>"}

Usage Examples

The examples in this section are based on the following sample graph:

CREATE (:Article {
  uri: "https://neo4j.com/blog/pokegraph-gotta-graph-em-all/",
  body: "These days I’m rarely more than a few feet away from my Nintendo Switch and I play board games, card games and role playing games with friends at least once or twice a week. I’ve even organised lunch-time Mario Kart 8 tournaments between the Neo4j European offices!"
});

CREATE (:Article {
  uri: "https://en.wikipedia.org/wiki/Nintendo_Switch",
  body: "The Nintendo Switch is a video game console developed by Nintendo, released worldwide in most regions on March 3, 2017. It is a hybrid console that can be used as a home console and portable device. The Nintendo Switch was unveiled on October 20, 2016. Nintendo offers a Joy-Con Wheel, a small steering wheel-like unit that a Joy-Con can slot into, allowing it to be used for racing games such as Mario Kart 8."
});

We can use this procedure to extract categories from the Article node. The text that we want to analyze is stored in the body property of the node, so we’ll need to specify that via the nodeProperty configuration parameter.

The following streams the categories for the Pokemon article:

MATCH (a:Article {uri: "https://neo4j.com/blog/pokegraph-gotta-graph-em-all/"})
CALL apoc.nlp.gcp.classify.stream(a, {
  key: $apiKey,
  nodeProperty: "body"
})
YIELD value
UNWIND value.categories AS category
RETURN category;
Table 2. Results
category

{name: "/Games", confidence: 0.91}

We get back only one category We could then apply a Cypher statement that creates one node per category and a CATEGORY relationship from each of those nodes back to the Article node.

The following streams the categories for the Pokemon article and then creates nodes for each category:

MATCH (a:Article {uri: "https://neo4j.com/blog/pokegraph-gotta-graph-em-all/"})
CALL apoc.nlp.gcp.classify.stream(a, {
  key: $apiKey,
  nodeProperty: "body"
})
YIELD value
UNWIND value.categories AS category
MERGE (c:Category {name: category.name})
MERGE (a)-[:CATEGORY]->(c)

If we want to automatically create a category graph, see apoc.nlp.gcp.classify.graph.