Python & neo4j - Fuck the jvm Stephen McCullough / Pybelfast Jan 2019 

About me.. cos it is all about me, me, me!!!! • Lead Developer @ Futrli - we’re hiring • I co-organise pyBelfast, BelfastRuby and BelfastElixir • I’ll try and behave and not curse… • You can find me on the inter web on most things as @swmcc apart from twitter! 

Python & neo4j - Fuck the jvm • First off… I don’t mean “Fuck the jvm” • It is an incendiary title • I find graph databases interesting/fun • I don’t want to have to learn a new language to play with something • Python has a nice eco system around it for neo4j • Standing on others shoulders - Grant Dickerson 

What is a graph DB? • Composed of nodes (vertices) & relationships (edges) • Completely different paradigm from relationship databases • It focuses on the relationships between values and commonalities among a ‘set’ of values • Designed to treat the relationships between the data as equally important to the data itself • Intended to hold data without constricting it to a pre- defined model 

Use cases for a graph db • Fraud Detection & Analytics Solution • Ecomm fraud, insurance fraud, link analysis • Knowledge Graph • Asset management, Inventory • Recommendation Engines • Product recommendations, social recommendations • Identity & Access management • Cross referencing of business objects 

Knowledge Graph • It represents a knowledge domain. • Connects things of different types in a systematic way. • Encodes knowledge arranged in a network of nodes and links rather than tables of rows and columns • Grow a semantic network of facts about “things” and can use it for data integration, knowledge discovery, and in-depth analyses. 

For example • Homer Simpson (is friends with) with Kenny & Carl • Kenny (is friends with) Carl 

Nodes • A node is a “vertex between edges that may hold data” • Or as I call it “a wee box of data stores” • [name: Homer] • [name: Lenny] • [name: Carl] 

What does it look like? 

Cypher • Cypher is a graph query language supported by neo4j • Based on pattern matching and a SQL-like syntax • …. when I was doing this before I didn’t use it much • I used Gremlin • DSL for Groovy • Wanted to use either ruby or python for an idea I’ve had since 2013 

Is python fit enough? • I tried this out with ruby in 2013 • It didn’t go well, as you can imagine. • There were libraries but most weren’t fit for purpose • Reason that I went to Groovy • However its now 2019 and there is a very well supported “official” packages for python • Neo4j-python-driver • https://github.com/neo4j-examples/movies-python-bolt • Py2neo • https://py2neo.org/v4/ 

Example Code from py2neo import Node nicole = Node("Person", name="Nicole", age=24) drew = Node("Person", name="Drew", age=20) mtdew = Node("Drink", name="Mountain Dew", calories=9000) cokezero = Node("Drink", name="Coke Zero", calories=0) coke = Node("Manufacturer", name="Coca Cola") pepsi = Node("Manufacturer", name="Pepsi") graph.create(nicole | drew | mtdew | cokezero | coke | pepsi) from scripts.vis import draw options = {"Person": "name", "Drink": "name", "Manufacturer": "name"} draw(graph, options) from py2neo import Relationship graph.create(Relationship(nicole, "LIKES", cokezero)) graph.create(Relationship(nicole, "LIKES", mtdew)) graph.create(Relationship(drew, "LIKES", mtdew)) graph.create(Relationship(coke, "MAKES", cokezero)) graph.create(Relationship(pepsi, "MAKES", mtdew)) draw(graph, options) 

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The Wire 

The GRROM 

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The Nodes - The Wire • All have common attributes: • Name • First / Last Appearance • Title • Section • Relationship between nodes 

Joe
 “Proposition Joe” Stewart name: Joe Stewart alias: Prop Joe first_apperance: 1.09 last_apperance: 5.04 section: The Street rank: Kingpin affiliation: [east-side, new day co- op] 

Russell
 “Stringer” Bell name: Russell Bell alias: Stringer first_apperance: 1.01 last_apperance: 3.12 section: The Street rank: Street Boss affiliation: [west-side, new-day co- op, b&b properties] 

Cedric Daniels name: Cedric Daniels alias: first_apperance: 1.01 last_apperance: 5.10 section: The Law rank: [Lieutenant, Major, Colonel, Chief Deputy Ops, Commissioner, ] affiliation: [police, lawyer] 

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Why do this??? • It doesn’t remind me of my day to day to work: • Not taking a section of a monolith and making a ‘micro service’ out of it • Not creating an API so that a front end can use it and display information • Nothing at all to do with my work • It is FUCKING FUN (for me at least). 

Going to do the following • Possibly come back at some stage and give you an actual talk on this, if there is interest • Will blog about it • Want to help me, please get in touch