fix: add entity index creation query

src/retriever.js

@@ -1,8 +1,8 @@
-import { ChatOpenAI } from '@langchain/openai'
 import { z } from 'zod'
 import 'neo4j-driver'
 import { Neo4jGraph } from '@langchain/community/graphs/neo4j_graph'
 import { ChatPromptTemplate, PromptTemplate } from '@langchain/core/prompts'
+import { ChatOpenAI } from '@langchain/openai'
 import { Neo4jVectorStore } from '@langchain/community/vectorstores/neo4j_vector'
 import { OpenAIEmbeddings } from '@langchain/openai'
 import { createStructuredOutputRunnable } from 'langchain/chains/openai_functions'
@@ -67,6 +67,10 @@ const entityChain = createStructuredOutputRunnable({
   llm
 })
 
+await graph.query(
+  'CREATE FULLTEXT INDEX entity IF NOT EXISTS FOR (e:__Entity__) ON EACH [e.id]'
+)
+
 /**
  * Collects the neighborhood of entities mentioned in the question.
  *
@@ -80,18 +84,18 @@ async function structuredRetriever(question) {
   for (const entity of entities.names) {
     const response = await graph.query(
       `CALL db.index.fulltext.queryNodes('entity', $query, 
-              {limit:2})
-              YIELD node,score
-              CALL {
-                  MATCH (node)-[r:!MENTIONS]->(neighbor)
-                  RETURN node.id + ' - ' + type(r) + ' -> ' + neighbor.id AS 
-                  output
-                  UNION
-                  MATCH (node)<-[r:!MENTIONS]-(neighbor)
-                  RETURN neighbor.id + ' - ' + type(r) + ' -> ' +  node.id AS 
-                  output
-              }
-              RETURN output LIMIT 50`,
+            {limit:2})
+            YIELD node,score
+            CALL {
+                MATCH (node)-[r:!MENTIONS]->(neighbor)
+                RETURN node.id + ' - ' + type(r) + ' -> ' + neighbor.id AS 
+                output
+                UNION
+                MATCH (node)<-[r:!MENTIONS]-(neighbor)
+                RETURN neighbor.id + ' - ' + type(r) + ' -> ' +  node.id AS 
+                output
+            }
+            RETURN output LIMIT 50`,
       { query: generateFullTextQuery(entity) }
     )
 
@@ -141,8 +145,6 @@ const retrieverChain = RunnableSequence.from([
   retriever
 ])
 
-// const combineDocumentsChain = RunnableSequence.from([combineDocuments])
-
 const answerChain = answerPrompt.pipe(llm).pipe(new StringOutputParser())
 
 const chain = RunnableSequence.from([
@@ -193,14 +195,11 @@ async function ask(question) {
   logResult(answer)
 }
 
-await ask('Who is the billionaire in the Avengers group?')
-await ask('What is his other name?')
 await ask('Loki is a native of which planet?')
-await ask('What is the name of his brother')
-await ask('What is the other name of Bruce Banner?')
-await ask('Where is the Stark Tower located?')
-await ask('Who is Loki?')
-await ask('Who is Jarvis?')
+await ask('What is the name of his brother?')
+await ask('Who is the villain among the two?')
+await ask('Who is Tony Stark?')
+await ask('Does he own the Stark Tower?')
 
 await graph.close()
 await neo4jVectorIndex.close()