1 Cisco Unified Application Environment Developers Conference 2008© 2008 Cisco Systems, Inc. All...

1Cisco Unified Application Environment Developers Conference 2008 © 2008 Cisco Systems, Inc. All rights reserved. Cisco Public

Introduction to Etch

Scott Comer

Technical Leader

[email protected]


Welcome

Introduction to Etch

– what it is

– how to use it to build a network service

– where it is going


What is a network service?

Messages and formats

Action: query or control; Event

Definitions / abstractions / rules

Players / authorization / transports


What is Etch?

Network service description language

Compiler

Runtime


Why Etch?

Language independence

Transport independence

Small and quick – high performance

Symmetric


Relationship to Cisco Unified Application Environment

Application environment is a federation of services

Formalized APIs

Programmable and extensible

Enhances the Developer Experience


Demos

Hello World


Hello World Example Overview

Client Server

Etch Etch


Hello World C# Demo

Create etch interface

Generate server and client code

Implement the hello message in the server

Call the hello message from the client

Build the server and client

Run the server and client


Sequence Diagram

Client Listener Server

Listen


Sequence Diagram


Connect

Listen


Sequence Diagram


Create ServerSession

Connect

Listen


Sequence Diagram



Connect

Listen

Sends HelloTo Server


Sequence Diagram



Disconnect

Connect

Listen

Sends HelloTo Server


Summary Hello World C# Demo

Etch generated most of code.

Generated code does all of the plumbing.

Developer only needs to be concerned with implementing and using the interfaces.

Less than 5 minutes to build a simple client / server application.


Hello World Java Demo

Show using Etch in Eclipse

Start with existing demo

Add client callback


Summary Hello World Demo

Java has similar experience to C#

Message sending looks just like procedure calls

Generated codes may be easily integrated


Etch Language


Etch Language

Messagesint add( int x, int y )

Native typesboolean, byte, short, int, long, float, double, string, object, List, Map, Set, arrays of those things

Structured data typesstruct Point( double x, double y, double z )

External data types@Extern( java, “com.company.User”, … )

extern User


Etch Language, part 2

Constantsconst int ZERO = 0

Enumerationsenum PrimaryColor ( RED, GREEN, BLUE )

Exceptionsexception LoginFailed( int code, string msg )



Attributes@Direction( which ) – server, client, both

@Oneway

@Timeout( millis )

@Authorize( method, args … )



Formal Comments

/** * Adds two numbers together. * @param x the first number. * @param y the second number. * @return the sum of the arguments. */int add( int x, int y )



Mixins

service Foo{

mixin Barmixin Baz

}


Etch Language Example

module com.acme

service GeoFun{

const double DEFAULT_HOW_FAR = 10 // miles

const int DEFAULT_NUM_LANDMARKS = 20

struct Point( double latitude, double longitude )

struct Landmark( Point where, string description )

void addLandmark( Landmark landmark )

void removeLandmark( Landmark landmark )

Landmark[] searchLandmarks( Point where, double how_far, int count )

}


Nitty Gritty Details

Compiler, architecture


Etch Compiler

Written in Java (runs anywhere)

Uses Templates (easier to port)

Bindings (java, csharp, …)


Etch Process

Etch Source EtchCompiler

Interface

StubRemote

ValueFactory

Helper

Base

Main Impl


Etch Inheritance

Interface

Remote Base

Impl


Etch Architecture

Stub

Remote

Transport

Impl

Main

Stub

Remote

Transport

Impl

Main


Etch Architecture

Stub

Remote

Transport

Impl

Main

Stub

Remote

Transport

Impl

Main


Etch Architecture

Stub

Remote

Transport

Impl

Main

Stub

Remote

Transport

Impl

Main


Etch Architecture

Stub

Remote

Transport

Impl

Main

Stub

Remote

Transport

Impl

Main


Etch Architecture

Stub

Remote

Transport

Impl

Main

Stub

Remote

Transport

Impl

Main


Runtime

Message model

Compiler support

Transport

Utilities


Message Model

Representation (type, fields & values)

Meta data

Generated code is transport independent


Transport

URI specification

Manages session

Moves messages

Message format is generic or transport specific(binary, xml, soap, …)


Transport, part 2

Transport services and propertiesAuthentication, session, logging, rate control, filtering

ProtocolsNow: TCP, TLS

Planned: JSON, UDP, AES, SOAP

ExtensibleJMS, REST, …


Transport, part 3

ValueFactory

StubRemote

Messagizer

Mailbox Manager

Packetizer

Stream

Security

Filter Chainauth

log

session

keep alive


More Demos

Distributed Map


Distributed Map Demo

Provides access to a shared Map

Add notification when values change

Example of session management


Roadmap

JSON, Python, C, Ruby bindings

More transports and transport modes

Web Services Gateway

Better Integration with IDEs, Maven


Etch will be Open Source!!!is


Where from here?

Distribution:

http://developer.cisco.com/web/cuae/etch

Source

https://etchproj.svn.sourceforge.net


Summary

Etch is a powerful tool that formalizes APIs used to access and extend Cisco Unified Application Environment

Etch automates many tedious and distracting tasks

Etch may be used in your own projects, and embedded in your own systems.


Q and A


Date post:	02-Jan-2016
Category:	Documents
Upload:	job-mitchell
View:	214 times
Download:	0 times

1 Cisco Unified Application Environment Developers Conference 2008© 2008 Cisco Systems, Inc. All...

Documents