Avoiding the Legacy Trap Round 1: the New Web Development Stack 1 - PowerPoint PPT Presentation

Avoiding the Legacy Trap Round 1: the New Web Development Stack 1

---- DRAFT ---- or a 30 minute fly-by 2

What is a Legacy Trap and how is it avoided? • In this context: adopting the familiar for unsuitable use continued investment beyond economic life • always consider a replacement option plan best path from status quo to goal ignore "sunk" costs 3

Fading Technologies • XML ==> XHTML, XForms becoming niche approaches • cross-compiling and device-specific applications write once, use every where is still alive • relational DBMS and normalization for the Web JSON, map/reduce, indexed native store schema & parsing only as needed • Tightly coupled client-server web applications fault-tolerance through local storage off-line mode provide recovery and let it fail rather than fighting inevitable 4

5 Essential Technologies • HTML (aka HTML5) • NoSQL database [CouchDB] • Server-side JavaScript [Node.JS] • AMQP (+ SMS, MMS, IM, BT, 3G, ...) [RabbitMQ] • Thin Client / Kiosk / Mobile [LiteClient] 5

HTML (aka HTML5) • as of January: HTML is a "live standard" with support of browser-makers • commitment to open, cross-device platform for Web • current features include: 6

NoSQL database [CouchDB] • JSON document store • fast B2-tree indexing • built-in concurrence, fault-tolerance (Erlang OTC) • built-in replication / sync with collision resolution • deployable on cellphones and server clusters • introduces 2-tier applications, app update by sync 7

Server-side JavaScript [Node.JS] 8

AMQP (+ SMS, MMS, IM, BT, 3G, ...) [RabbitMQ] 9

Thin Client / Kiosk / Mobile [LiteClient] 10

5 Seed Projects • HUP2x -- Heads-UP double entry • TABS -- Track Assets / Balance Stocks • SNAPS -- Scanned Network-Available PDF Store • MOW5 -- Medical Officer Workstation (HTML5) • OpStats -- Operational Status & Statistics 11

HUP2x: Heads-Up double entry • Data entry from scanned forms where: Cursor next to hand-recorded value No mouse, no customized paper forms Separately entered twice for error correction • Improvements over traditional heads-down: Data linked to image --> process improvements Images provide backup to patient summaries 12

TABS: Track Assets / Balance Stocks 13

SNAPS: Scanned Network-Available PDF Store 14

MOW5: Medical Officer Workstation (HTML5) 15

OpStats: Operational Status & Statistics 16