Ryan Boyd, Head of Developer Relations, Neo4j

1. Utilizing Powerful Extensions
Ryan Boyd
Developer Relations, Neo4j

2. ~ 30 things in 30 minutes

3. Neo4j Developer Surface
Native LanguageDrivers
BOLT User Defined
Procedure
2000-2010 0.x Embedded Java API
2010-2014 1.x REST
2014-2015 2.x Cypher over HTTP
2016 3.0.x Bolt, Official Language Drivers, User Defined Procedures
2016 3.1.x User Defined Functions
2017 3.2.x User Defined Aggregation Functions

4. Neo4j Developer Surface
Native LanguageDrivers
BOLT User Defined
Procedure
2000-2010 0.x Embedded Java API
2010-2014 1.x REST
2014-2015 2.x Cypher over HTTP
2016 3.0.x Bolt, Official Language Drivers, User Defined Procedures
2016 3.1.x User Defined Functions
2017 3.2.x User Defined Aggregation Functions

5. Neo4j Bolt Drivers

6. Official Drivers

8. Community Drivers

9. Neo4j Developer Surface
Native LanguageDrivers
BOLT User Defined
Procedure
2000-2010 0.x Embedded Java API
2010-2014 1.x REST
2014-2015 2.x Cypher over HTTP
2016 3.0.x Bolt, Official Language Drivers, User Defined Procedures
2016 3.1.x User Defined Functions
2017 3.2.x User Defined Aggregation Functions

10. Procedures
Functions
Aggregate Functions

11. Can be written in any JVM language

12. User Defined
Procedures
12

13. Callable Standalone
and in
Cypher Statements

14. CALL example.search('User','name:Brook*')

15. public class FullTextIndex {
@Context
public GraphDatabaseService db;
@Procedure( name = "example.search", mode = Procedure.Mode.READ )
public Stream<SearchHit> search( @Name("index") String index,
@Name("query") String query ) {
if( !db.index().existsForNodes( index )) {
return Stream.empty();
}
return db.index().forNodes( index ).query( query ).stream()
.map( SearchHit::new );
}
public static class SearchHit {
public final Node node;
SearchHit(Node node) { this.node = node; }
}
}

16. public class FullTextIndex {
@Context
public GraphDatabaseService db;
@Procedure( name = "example.search", mode = Procedure.Mode.READ )
public Stream<SearchHit> search( @Name("index") String index,
@Name("query") String query ) {
if( !db.index().existsForNodes( index )) {
return Stream.empty();
}
return db.index().forNodes( index ).query( query ).stream()
.map( SearchHit::new );
}
public static class SearchHit {
public final Node node;
SearchHit(Node node) { this.node = node; }
}
}

17. public class FullTextIndex {
@Context
public GraphDatabaseService db;
@Procedure( name = "example.search", mode = Procedure.Mode.READ )
public Stream<SearchHit> search( @Name("index") String index,
@Name("query") String query ) {
if( !db.index().existsForNodes( index )) {
return Stream.empty();
}
return db.index().forNodes( index ).query( query ).stream()
.map( SearchHit::new );
}
public static class SearchHit {
public final Node node;
SearchHit(Node node) { this.node = node; }
}
}

18. try ( Driver driver = GraphDatabase.driver( "bolt://localhost",
Config.build().toConfig() ) ) {
try ( Session session = driver.session() ) {
String call = "CALL example.search('User',$query)";
Map<String,Object> params = singletonMap( "query", "name:Brook*");
StatementResult result = session.run( call, params);
while ( result.hasNext() {
// process results
}
}
}

19. try ( Driver driver = GraphDatabase.driver( "bolt://localhost",
Config.build().toConfig() ) ) {
try ( Session session = driver.session() ) {
String call = "CALL example.search('User',$query)";
Map<String,Object> params = singletonMap( "query", "name:Brook*");
StatementResult result = session.run( call, params);
while ( result.hasNext() {
// process results
}
}
}

20. User Defined
Functions
20

21. Useable in any Cypher
expression or lightweight
computation

22. RETURN example.join(['Hello', 'World'],' ')
=> "Hello World"

23. public class Join {
@UserFunction
@Description("example.join(['s1','s2',...], delimiter)
- join the given strings with the given delimiter.")
public String join(
@Name("strings") List<String> strings,
@Name(value = "delimiter", defaultValue = ",") String delimiter ) {
if ( strings == null || delimiter == null ) {
return null;
}
return String.join( delimiter, strings );
}
}

24. public class Join {
@UserFunction
@Description("example.join(['s1','s2',...], delimiter)
- join the given strings with the given delimiter.")
public String join(
@Name("strings") List<String> strings,
@Name(value = "delimiter", defaultValue = ",") String delimiter ) {
if ( strings == null || delimiter == null ) {
return null;
}
return String.join( delimiter, strings );
}
}

25. public class Join {
@UserFunction
@Description("example.join(['s1','s2',...], delimiter)
- join the given strings with the given delimiter.")
public String join(
@Name("strings") List<String> strings,
@Name(value = "delimiter", defaultValue = ",") String delimiter ) {
if ( strings == null || delimiter == null ) {
return null;
}
return String.join( delimiter, strings );
}
}

26. try ( Driver driver = GraphDatabase.driver( "bolt://localhost",
Config.build().toConfig() ) )
{
try ( Session session = driver.session() )
{
String query = "RETURN example.join(['Hello', 'World']) AS result";
String result = session.run( query )
.single().get( "result" ).asString();
}
}

27. User Defined
Aggregation Functions
27

28. Custom, efficient aggregations
for Data Science and BI

29. UNWIND ['abc', 'abcd', 'ab'] AS string
RETURN example.longestString(string)
=> 'abcd'

30. public class LongestString {
@UserAggregationFunction
@Description( "aggregates the longest string found" )
public LongStringAggregator longestString() {
return new LongStringAggregator();
}
public static class LongStringAggregator {
private int longest;
private String longestString;
@UserAggregationUpdate
public void findLongest( @Name( "string" ) String string ) {
if ( string != null && string.length() > longest) {
longest = string.length();
longestString = string;
}
}
@UserAggregationResult
public String result() { return longestString; }
}
}

31. public class LongestString {
@UserAggregationFunction
@Description( "aggregates the longest string found" )
public LongStringAggregator longestString() {
return new LongStringAggregator();
}
public static class LongStringAggregator {
private int longest;
private String longestString;
@UserAggregationUpdate
public void findLongest( @Name( "string" ) String string ) {
if ( string != null && string.length() > longest) {
longest = string.length();
longestString = string;
}
}
@UserAggregationResult
public String result() { return longestString; }
}
}

32. public class LongestString {
@UserAggregationFunction
@Description( "aggregates the longest string found" )
public LongStringAggregator longestString() {
return new LongStringAggregator();
}
public static class LongStringAggregator {
private int longest;
private String longestString;
@UserAggregationUpdate
public void findLongest( @Name( "string" ) String string ) {
if ( string != null && string.length() > longest) {
longest = string.length();
longestString = string;
}
}
@UserAggregationResult
public String result() { return longestString; }
}
}

33. public class LongestString {
@UserAggregationFunction
@Description( "aggregates the longest string found" )
public LongStringAggregator longestString() {
return new LongStringAggregator();
}
public static class LongStringAggregator {
private int longest;
private String longestString;
@UserAggregationUpdate
public void findLongest( @Name( "string" ) String string ) {
if ( string != null && string.length() > longest) {
longest = string.length();
longestString = string;
}
}
@UserAggregationResult
public String result() { return longestString; }
}
}

34. try ( Driver driver = GraphDatabase.driver( "bolt://localhost",
Config.build().toConfig() ) ) {
try ( Session session = driver.session() ) {
String query = "UNWIND ['abc', 'abcd', 'ab'] AS string " +
"RETURN example.longestString(string) AS result";
String result = session.run(query).single().get("result").asString();
}
}

37. Awesome Procedures
On Cypher

40. > 400
procedures and functions

43. Data Integration

44. Load from a relational database

45. apoc.load.jdbc
WITH "jdbc:mysql://localhost:3306/northwind?user=root" AS url
CALL apoc.load.jdbc(url,"products")
YIELD row
MERGE (p:Product {id: row.ProductID})
SET p.name = row.ProductName, p.unitPrice = row.UnitPrice

46. WITH "jdbc:mysql://localhost:3306/northwind?user=root" AS url
CALL apoc.load.jdbc(url,"products")
YIELD row
MERGE (p:Product {id: row.ProductID})
SET p.name = row.ProductName, p.unitPrice = row.UnitPrice
Execute procedure

47. Apply Cypher transformation
WITH "jdbc:mysql://localhost:3306/northwind?user=root" AS url
CALL apoc.load.jdbc(url,"products")
YIELD row
MERGE (p:Product {id: row.ProductID})
SET p.name = row.ProductName, p.unitPrice = row.UnitPrice

48. Load XML

49. apoc.load.xml
CALL apoc.load.xml('http://overpass.osm.rambler.ru/cgi/xapi_meta?*[bbox=11.54,48.14,11.543,48.145]')
YIELD value
UNWIND value["_children"] AS child
WITH child WHERE child["_type"] = "node"
WITH child.id AS id,
child.lat AS latitude,
child.lon AS longitude,
child["user"] AS userName
MERGE (point:Point {id: id})
SET point.latitude = latitude,
point.longitude = longitude
MERGE (user:User {name: userName})
MERGE (user)-[:EDITED]->(point)

50. Execute procedure
CALL apoc.load.xml('http://overpass.osm.rambler.ru/cgi/xapi_meta?*[bbox=11.54,48.14,11.543,48.145]')
YIELD value
UNWIND value["_children"] AS child
WITH child WHERE child["_type"] = "node"
WITH child.id AS id,
child.lat AS latitude,
child.lon AS longitude,
child["user"] AS userName
MERGE (point:Point {id: id})
SET point.latitude = latitude,
point.longitude = longitude
MERGE (user:User {name: userName})
MERGE (user)-[:EDITED]->(point)

51. UNWIND the array of elements
CALL apoc.load.xml('http://overpass.osm.rambler.ru/cgi/xapi_meta?*[bbox=11.54,48.14,11.543,48.145]')
YIELD value
UNWIND value["_children"] AS child
WITH child WHERE child["_type"] = "node"
WITH child.id AS id,
child.lat AS latitude,
child.lon AS longitude,
child["user"] AS userName
MERGE (point:Point {id: id})
SET point.latitude = latitude,
point.longitude = longitude
MERGE (user:User {name: userName})
MERGE (user)-[:EDITED]->(point)

52. Filter rows
CALL apoc.load.xml('http://overpass.osm.rambler.ru/cgi/xapi_meta?*[bbox=11.54,48.14,11.543,48.145]')
YIELD value
UNWIND value["_children"] AS child
WITH child WHERE child["_type"] = "node"
WITH child.id AS id,
child.lat AS latitude,
child.lon AS longitude,
child["user"] AS userName
MERGE (point:Point {id: id})
SET point.latitude = latitude,
point.longitude = longitude
MERGE (user:User {name: userName})
MERGE (user)-[:EDITED]->(point)

53. Apply Cypher transformation
CALL apoc.load.xml('http://overpass.osm.rambler.ru/cgi/xapi_meta?*[bbox=11.54,48.14,11.543,48.145]')
YIELD value
UNWIND value["_children"] AS child
WITH child WHERE child["_type"] = "node"
WITH child.id AS id,
child.lat AS latitude,
child.lon AS longitude,
child["user"] AS userName
MERGE (point:Point {id: id})
SET point.latitude = latitude,
point.longitude = longitude
MERGE (user:User {name: userName})
MERGE (user)-[:EDITED]->(point)
MERGE (point:Point {id: id})
SET point.latitude = latitude,
point.longitude = longitude
MERGE (user:User {name: userName})
MERGE (user)-[:EDITED]->(point)

54. Load JSON

55. apoc.load.json
WITH "https://api.stackexchange.com/2.2/questions?pagesize=100&order=desc&sort=creation&tagged=neo4j&site=stackoverflow&filter=!5-i6Zw8Y)4W7vpy91PMYsKM-k9yzEsSC1_Uxlf" AS url
CALL apoc.load.json(url) YIELD value
UNWIND value.items AS q
MERGE (question:Question {id:q.question_id})
ON CREATE SET question.title = q.title,
question.share_link = q.share_link,
question.favorite_count = q.favorite_count
MERGE (owner:User {id:q.owner.user_id})
ON CREATE SET owner.display_name = q.owner.display_name
MERGE (owner)-[:ASKED]->(question)
FOREACH (tagName IN q.tags |
MERGE (tag:Tag {name:tagName}) MERGE (question)-[:TAGGED]->(tag))
FOREACH (a IN q.answers |
MERGE (question)<-[:ANSWERS]-(answer:Answer {id:a.answer_id})
MERGE (answerer:User {id:a.owner.user_id})
ON CREATE SET answerer.display_name = a.owner.display_name
MERGE (answer)<-[:PROVIDED]-(answerer)
)

56. WITH "https://api.stackexchange.com/2.2/questions?pagesize=100&order=desc&sort=creation&tagged=neo4j&site=stackoverflow&filter=!5-i6Zw8Y)4W7vpy91PMYsKM-k9yzEsSC1_Uxlf" AS url
CALL apoc.load.json(url) YIELD value
UNWIND value.items AS q
MERGE (question:Question {id:q.question_id})
ON CREATE SET question.title = q.title,
question.share_link = q.share_link,
question.favorite_count = q.favorite_count
MERGE (owner:User {id:q.owner.user_id})
ON CREATE SET owner.display_name = q.owner.display_name
MERGE (owner)-[:ASKED]->(question)
FOREACH (tagName IN q.tags |
MERGE (tag:Tag {name:tagName}) MERGE (question)-[:TAGGED]->(tag))
FOREACH (a IN q.answers |
MERGE (question)<-[:ANSWERS]-(answer:Answer {id:a.answer_id})
MERGE (answerer:User {id:a.owner.user_id})
ON CREATE SET answerer.display_name = a.owner.display_name
MERGE (answer)<-[:PROVIDED]-(answerer)
)
Use FOREACH for arrays within a row
FOREACH (tagName IN q.tags |
MERGE (tag:Tag {name:tagName}) MERGE (question)-[:TAGGED]->(tag))
FOREACH (a IN q.answers |
MERGE (question)<-[:ANSWERS]-(answer:Answer {id:a.answer_id})
MERGE (answerer:User {id:a.owner.user_id})
ON CREATE SET answerer.display_name = a.owner.display_name
MERGE (answer)<-[:PROVIDED]-(answerer)
)

57. Graph Refactorings

58. apoc.refactor.mergeNodes
MATCH (n:Person)
WITH n.email AS email, collect(n) as people
WHERE size(people) > 1
CALL apoc.refactor.mergeNodes(people)
YIELD node
RETURN node

59. apoc.refactor.mergeNodes
MATCH (n:Person)
WITH n.email AS email, collect(n) as people
WHERE size(people) > 1
CALL apoc.refactor.mergeNodes(people)
YIELD node
RETURN node

60. apoc.create.addLabels
MATCH (n:Movie)
CALL apoc.create.addLabels( id(n), [ n.genre ] ) YIELD node
REMOVE node.genre
RETURN node

61. Cypher Execution

62. Run large scale updates
CALL apoc.periodic.iterate(
'MATCH (n:Person) RETURN n',
'SET n.name = n.firstName + " " + n.lastName',
{batchSize:10000, parallel:true})

63. Utility Functions

64. Compute soundex encoding of a string
CALL apoc.text.phonetic('Hello, dear User!')
YIELD value
RETURN value
// will return 'H436'

65. How similar do two strings sound?
CALL apoc.text.phoneticDelta(
'Hello Mr Rabbit', 'Hello Mr Ribbit')
// will return '4' (very similar)

66. Extract domain names
WITH 'http://www.example.com/all-the-things' AS url
RETURN apoc.data.domain(url)
// will return 'www.example.com'

67. Date to Timestamp
RETURN apoc.date.parse(
'2015/03/25 03:15:59',
's',
'yyyy/MM/dd HH:mm:ss'
)
// will return 1427253359

68. Timestamp to Date
RETURN apoc.date.format(
1427253359,
's',
'yyyy/MM/dd HH:mm:ss'
)
// will return "2015/03/25 03:15:59"

69. And many more!

70. Graph Aided Search

74. dzone.com/refcardz/graph-powered-search-neo4j-amp-elasticsearch

75. Versioned Graphs

78. CALL graph.versioner.init('Person',
{ssn: 123456789, name: 'Marco'},
{address: 'Via Roma 11'}
)
Create node

79. CALL graph.versioner.init('Person',
{ssn: 123456789, name: 'Marco'},
{address: 'Via Roma 11'}
)
Immutable properties

80. CALL graph.versioner.init('Person',
{ssn: 123456789, name: 'Marco'},
{address: 'Via Roma 11'}
)
State properties

81. MATCH (p:Person {name: "Marco"})
WITH p
CALL graph.versioner.update(p, {address: 'Via Roma 12'})
YIELD node
RETURN node
Update state

82. MATCH (p:Person {name: "Marco"})
WITH p
CALL graph.versioner.update(p, {address: 'Via Roma 12'})
YIELD node
RETURN node
Pass in the new state

83. Spatial

85. lyonwj.com/2016/08/09/neo4j-spatial-procedures-congressional-boundaries/

86. CALL spatial.addWKTLayer('geom', 'wkt')
Create spatial index

87. CREATE (d:District {...})
SET d.wkt = 'MULTIPOLYGON(((23.22, ... )))'
Add spatial property to nodes

88. MATCH (d:District)
WITH collect(d) AS districts
CALL spatial.addNodes('geom', districts) YIELD node
RETURN count(*)
Add nodes to spatial index

89. CALL spatial.withinDistance('geom',
{latitude: 37.563440, longitude: -122.322265}, 1)
YIELD node AS d
WITH d, d.wkt AS wkt, d.state AS state, d.district AS district
LIMIT 1
MATCH (d)<-[:REPRESENTS]-(l:Legislator)
MATCH (l)-[:SERVES_ON]->(c:Committee)
MATCH (c)<-[:REFERRED_TO]-(b:Bill)
MATCH (b)-[:DEALS_WITH]->(s:Subject)
RETURN *
Query nodes by location

90. CALL spatial.withinDistance('geom',
{latitude: 37.563440, longitude: -122.322265}, 1)
YIELD node AS d
WITH d, d.wkt AS wkt, d.state AS state, d.district AS district
LIMIT 1
MATCH (d)<-[:REPRESENTS]-(l:Legislator)
MATCH (l)-[:SERVES_ON]->(c:Committee)
MATCH (c)<-[:REFERRED_TO]-(b:Bill)
MATCH (b)-[:DEALS_WITH]->(s:Subject)
RETURN *
Finds nodes within 1km

91. CALL spatial.withinDistance('geom',
{latitude: 37.563440, longitude: -122.322265}, 1)
YIELD node AS d
WITH d, d.wkt AS wkt, d.state AS state, d.district AS district
LIMIT 1
MATCH (d)<-[:REPRESENTS]-(l:Legislator)
MATCH (l)-[:SERVES_ON]->(c:Committee)
MATCH (c)<-[:REFERRED_TO]-(b:Bill)
MATCH (b)-[:DEALS_WITH]->(s:Subject)
RETURN *
Continue with the rest of the query

92. lyonwj.com/2016/08/09/neo4j-spatial-procedures-congressional-boundaries/

93. Graph Based
Machine Learning

96. CREATE (n:News)
SET n.text = "Scores of people were already lying dead or
injured inside a crowded Orlando nightclub,
and the police had spent hours trying to connect with the
gunman and end the situation without further violence.
But when Omar Mateen threatened to set off explosives, the
police decided to act, and pushed their way through a
wall to end the bloody standoff."
Annotating text

97. MATCH (n:News)
CALL ga.nlp.annotate({text: n.text, id: id(n)})
YIELD result
MERGE (n)-[:HAS_ANNOTATED_TEXT]->(result)
RETURN result
Annotating text

98. MATCH (n:News)
CALL ga.nlp.annotate({text: n.text, id: id(n)})
YIELD result
MERGE (n)-[:HAS_ANNOTATED_TEXT]->(result)
RETURN result
Execute procedure

99. MATCH (n:News)
CALL ga.nlp.annotate({text: n.text, id: id(n)})
YIELD result
MERGE (n)-[:HAS_ANNOTATED_TEXT]->(result)
RETURN result
Relate to text node

101. Graph Visualization
101

105. var viz;
function draw() {
var config = {
container_id: "viz",
server_url: "bolt://localhost:7687",
server_user: "neo4j",
server_password: "sorts-swims-burglaries",
labels: {
"Character": {
"caption": "name",
"size": "pagerank",
"community": "community"
}
},
relationships: {
"INTERACTS": {
"thickness": "weight",
"caption": false
}
},
initial_cypher: "MATCH (n)-[r:INTERACTS]->(m) RETURN *"
};
viz = new NeoVis.default(config);
viz.render();
}

106. var viz;
function draw() {
var config = {
container_id: "viz",
server_url: "bolt://localhost:7687",
server_user: "neo4j",
server_password: "sorts-swims-burglaries",
labels: {
"Character": {
"caption": "name",
"size": "pagerank",
"community": "community"
}
},
relationships: {
"INTERACTS": {
"thickness": "weight",
"caption": false
}
},
initial_cypher: "MATCH (n)-[r:INTERACTS]->(m) RETURN *"
};
viz = new NeoVis.default(config);
viz.render();
}

107. var viz;
function draw() {
var config = {
container_id: "viz",
server_url: "bolt://localhost:7687",
server_user: "neo4j",
server_password: "sorts-swims-burglaries",
labels: {
"Character": {
"caption": "name",
"size": "pagerank",
"community": "community"
}
},
relationships: {
"INTERACTS": {
"thickness": "weight",
"caption": false
}
},
initial_cypher: "MATCH (n)-[r:INTERACTS]->(m) RETURN *"
};
viz = new NeoVis.default(config);
viz.render();
}

108. GraphQL

109. GraphQL is a query language for your API, and a
server-side runtime for executing queries by using a
type system you define for your data.
What is it?

110. GraphQL is a query language for your API, and a
server-side runtime for executing queries by using a
type system you define for your data.
What is it?

111. GraphQL is a query language for your API, and a
server-side runtime for executing queries by using a
type system you define for your data.
What is it?

112. GraphQL is a query language for your API, and a
server-side runtime for executing queries by using a
type system you define for your data.
What is it?
type Planet {
name: String
climate: String
}
type Character {
name: String
friends: [Character]
homeWorld: Planet
species: Species
}
type Species {
name: String
lifespan: Int
origin: Planet
}

113. Manual mapping code

115. Auto translating GraphQL → Cypher
github.com/neo4j-graphql/neo4j-graphql
github.com/neo4j-graphql/neo4j-graphql-js

116. Server Side Extension

118. dbms.unmanaged_extension_classes=org.neo4j.graphql=/graphql
dbms.security.procedures.whitelist=graphql.*
conf/neo4j.conf

119. CALL graphql.idl('
type Movie {
title: String!
released: Int
actors: [Person] @relation(name:"ACTED_IN",direction:IN)
}
type Person {
name: String!
born: Int
movies: [Movie] @relation(name:"ACTED_IN")
}'
)

120. WITH '{ Person(born: 1961) { name, born } }' as query, {} as params
CALL graphql.execute(query,params)
YIELD result
UNWIND result.Person as p
RETURN p.name, p.born

121. JavaScript Library

123. The GRAND stack

124. The GRAND stack
GraphQL
React
Apollo
Neo4j Database

125. import {neo4jgraphql} from 'neo4j-graphql-js';
const resolvers = {
Query: {
Movie(object, params, ctx, resolveInfo) {
return neo4jgraphql(object, params, ctx, resolveInfo);
}
}
};

126. dzone.com/refcardz/an-overview-of-graphql

127. How do I find out
about more cool stuff?

129. This Week in Neo4j - Developer Update
neo4j.com/tag/twin4j

130. Get Dressed: Neo4j Graph Gear Store
graphgearstore.com

131. Thank you for listening!

132. devrel@neo4j.com
@neo4j