Datasets by David Semeria

LM Datasets

Promote data and code sharing
on the web

David Semeria Ruby Social Club Milano
david@lmframework.com 16th December 2010
@hymanroth

Objects

Properties (data)

Methods (code)

Interface

LM Datasets 2

Objects

Properties (data)

Methods (code) Functional abstraction (GOOD)

Interface

LM Datasets 3

Objects

Properties (data) Data abstraction (BAD)


Interface

LM Datasets 4

Objects

Properties (data) Data abstraction (BAD)


Interface

Context: web services

Interoperability is key

LM Datasets 5

Interoperability
Browser

Twitter Facebook

Flickr Bit.ly

LM Datasets 6

Interoperability
Browser

Twitter Facebook

Flickr Bit.ly

LM Datasets 7

How Much Glue Code?

Twitter Facebook Facebook Twitter

Twitter Flickr Facebook Flickr

Twitter Bit.ly Facebook Bit.ly

Flickr Twitter Bit.ly Twitter

Flickr Facebook Bit.ly Facebook

Flickr Bit.ly Bitl.ly Flickr

12 sets of code

N2 - N
LM Datasets 8

The General Case

Browser

Service A Service B

Choose from N options Choose from N options

LM Datasets 9

The General Case

Browser

Service A Service B

Choose from N options Choose from N options

For N = 100 N2 – N = 99,900

LM Datasets 10

The Problem

APIs are better than nothing, but they
remain a major impediment to a fully
writable Web.

(The same applies to corporate intranets)

LM Datasets 11

Datasets

A generic Global data definitions

representation for
hierarchical data
Permissions

LIBRARY
( Front and back end )

Key word: GENERIC

LM Datasets 12

Hierarchical Structures
root

node

node node

leaf leaf

node node

leaf leaf leaf leaf

LM Datasets 13

A 'people' tree
root

people

sport music

Id: bowie Id: clapton
name: “David Bowie” name: “Eric Clapton”
soccer formula1

Id: maldini Id: gerrard Id: alonso Id: hamilton
name: “Paolo Maldini” name: “Steven Gerrard” name: “Fernando Alonso” name: “Lewis Hamilton”

LM Datasets 14

Generic Representation
S root node 1

node 2

node 1 leaf 1

leaf 2

node 2

R node 1 record

node 2 record

leaf 1 record

leaf 2 record
LM Datasets 15

JSON Example
ds: { s: { root: { people: 1 },
people: { music: 1, sport: 1 },
sport: { soccer: 1, forumla1: 1 },

music: { bowie: 1, clapton: 1 },
soccer: { maldini: 1, gerrard: 1 },
formula1: { alonso: 1, hamilton: 1 }
},

r: { people: { name: “People”, color: “green” },
music: { name: “Music” color: “black” },
sport: { name: “Sport” color: “white” },
soccer: { name: “Soccer”, color “red” },
formula1: { name: “Formula One”, color: “yellow” },

bowie: { name: “David Bowie”, color: “black” },
clapton: { name: “Eric Clapton”, color: “black” },
Maldini: { name: “Paolo Maldini”, color: “red” },
Gerrard: { name: “Steven Gerrard”, color: “red” },
Alonso: { name: “Fernando Alonso”, color: “red” },
Hamilton: { name: “Lewis Hamilton”, color: “silver” }
}
};

LM Datasets 16

Some Code Examples

➔ Leverage structure
➔ No need for recursive tree walking

➔ Leverage native operations
➔ Object property look-up much faster than array iteration.

LM Datasets 17

ID Exists ?

function IdExists (id){
return ds.r[id] != null;
}

LM Datasets 18

Node or Leaf ?

function nodeOrLeaf (id){
return (ds.s[id]) ?'node' :'leaf';
}

// assumes id exists

LM Datasets 19

Node contains id ?

function contains (nodeId, id){
if (ds.s[nodeId][id]){
return true;
}
return false
}

// assumes nodeId exists

LM Datasets 20

Parent Node

function parentNode (id){
for ( var k in ds.s ){
if (ds.s[k][id]){
return k;
}
}
//error
}

LM Datasets 21

Move Item

function move ( toNodeId, id ){
delete( ds.s[parenNode(id)][id] );
ds.s[toNodeId][id] = 1;
}

// assumes all ids exist

LM Datasets 22

Templates

DATASET

FLOW
+ HTML

TEMPLATES

LM Datasets 23

NODE TEMPLATE:
Flowing Templates
<DIV style = “border: 2px solid {color}; padding: 10px”></DIV>

LEAF TEMPLATE:
<P><SPAN style = “color:{color}”>{name}</SPAN></P>

LM Datasets 24

Flowing Templates
NODE TEMPLATE:
<DIV style = “border: 2px solid {color}; padding: 10px”></DIV>

LEAF TEMPLATE:
<P><SPAN style = “color:{color}”>{name}</SPAN></P>

OUTPUT:

David Bowie
Eric Clapton

Paolo Maldini
Steven Gerrard

Fernando Alonso
Lewis Hamilton

LM Datasets 25

Demo 1

LM Datasets 26

Data Definitions
EXAMPLE DEFINITION

Name Age
type string type integer
minLen 1 minVal 0
maxLen 50 maxVal 150
canBeNumeric false
regex (w| )*
function checkName

LM Datasets 27

Inheritance

PEOPLE PLACES THINGS ......

BASIC INFO

DETAILED INFO EMAIL INFO

DETAILED & EMAIL INFO

LM Datasets 28

Inheritance Across Root Types

PEOPLE SERVICE

BASIC INFO TWITTER

DETAILED INFO TWITTER INFO

TWITTER USER is a sub-type of both:
SERVICE / TWITTER / TWITTER INFO
TWITTER USER
PEOPLE / BASIC INFO

LM Datasets 29

Inheritance

Demo 2

LM Datasets 30

Normalization

Just like in the relational model, Dataset
normalization means we don't store the
same information twice....

LM Datasets 31

Viewsets and Recordsets

VIEWSET A VIEWSET B
refs

RECORD SET 1 sparse RECORD SET 2

SERVER

LM Datasets 32

Demo 3
windows

LIVERPOOL MILAN #1 MILAN #2 DREAM TEAM

view sets

VS - LIVERPOOL VS - MILAN VS – DREAM TEAM

RECORD SET FOOTBALLERS

SERVER

LM Datasets 33

Demo 3
windows


view sets



SERVER

LM Datasets 34

Demo 3
windows


view sets



SERVER

LM Datasets 35

Demo 3
windows


view sets



SERVER

LM Datasets 36

Demo 3
windows


view sets



SERVER

LM Datasets 37

Demo 3
windows


view sets



SERVER

LM Datasets 38

Summary

➔ Don't hide your data in objects

LM Datasets 39

Summary


➔ APIs can be an obstacle (representation)

LM Datasets 40

Summary



➔ Above all, KEEP IT GENERIC !!

LM Datasets 41

Summary



➔ Above all, KEEP IT GENERIC !!

Questions are welcome:
david@lmframework.com
@hymanroth

LM Datasets 42

Datasets by David Semeria

Recommandé

Recommandé

Contenu connexe

En vedette

En vedette (14)

Similaire à Datasets by David Semeria

Similaire à Datasets by David Semeria (20)

Dernier

Dernier (20)

Datasets by David Semeria