Slide 1
Slide 1 text
Tecnologías para
Servicios y servicios Web:
SOA, REST, GraphQL.
Slide 2
Slide 2 text
#Hola
Noé Domínguez-Porras (@noe_dgz)
Slide 3
Slide 3 text
Agenda
● La arquitectura de la Web
● SOA
● Service
● Web Service
● Tecnologías SOA: SOAP, WSDL, UDDI
● REST
● GraphQL
Slide 4
Slide 4 text
La arquitectura de la
Web
Sí, tiene una arquitectura oficial
Slide 5
Slide 5 text
1. The World Wide Web (WWW, or simply Web) is an information
space in which the items of interest, referred to as resources, are
identified by global identifiers called Uniform Resource Identifiers (URI).
Architectural Bases
a. Identification. URIs are used to identify resources.
b. Interaction. Web agents communicate using standardized protocols
that enable interaction through the exchange of messages which
adhere to a defined syntax and semantics.
c. Formats. Most protocols used for representation retrieval and/or
submission make use of a sequence of one or more messages,
which taken together contain a payload of representation data and
metadata, to transfer the representation between agents.
La web y su arquitectura
Slide 6
Slide 6 text
SOA
La arquitectura oficial de la Web
Slide 7
Slide 7 text
Estilo arquitectónico de SOA
Slide 8
Slide 8 text
• Analysis Paralysis
– Enterprise architectural efforts do not get off the ground
– Results in an inflexible architecture
• Over-Standardization
– Can’t satisfy different needs of different parts of an organization
– Results in a stovepipe development
• Rigidity in Data Definition
– Requires to support specific data definitions
Motivaciones para SOA
Slide 9
Slide 9 text
service-oriented architecture [w3c]
A set of components which can be invoked, and whose interface
descriptions can be published and discovered.
“A service is an abstract resource that represents a capability of
performing tasks that form a coherent functionality from the point of
view of providers entities and requesters entities.”
service-oriented architecture [Wikipedia]
“A software design and software architecture design pattern
based on structured collections of discrete software modules, known as
services“
Software Oriented Architecture
Slide 10
Slide 10 text
Estilo arquitectónico de SOA
Slide 11
Slide 11 text
An interaction model between three primary parties
– Service provider – publishes a service description and provides the
implementation for the service
– Service consumer – either use the uniform resource identifier (URI) for the
service description directly or can find the service description in a service
registry and bind and invoke the service.
– Service broker – provides and maintains the service registry (optional).
Estilo arquitectónico de SOA
Slide 12
Slide 12 text
Service
definición
Slide 13
Slide 13 text
Services are self-contained functions that provide access
to certain resources and capabilities, and can be
composed with other services to form different services
“A service is an abstract resource that represents a
capability of performing tasks that form a coherent
functionality from the point of view of providers entities
and requesters entities.” [W3C]
¿Qué es un servicio?
Slide 14
Slide 14 text
Web Service
definición
Slide 15
Slide 15 text
[W3C]
There are many things that might be called "Web services" in the world at
large. However, for the purpose of this Working Group and this
architecture, and without prejudice toward other definitions, we will use
the following definition:
A Web service is a software system designed to support interoperable
machine-to-machine interaction over a network. It has an interface
described in a machine-processable format (specifically WSDL). Other
systems interact with the Web service in a manner prescribed by its
description using SOAP-messages, typically conveyed using HTTP with an
XML serialization in conjunction with other Web-related standards.
Web Services
Slide 16
Slide 16 text
Tecnologías SOA
SOAP
Use a protocol independent from HTTP
Slide 17
Slide 17 text
Tecnologías SOA: SOAP.
SOAP follows the RPC model
Slide 18
Slide 18 text
Tecnologías SOA: SOAP.
Slide 19
Slide 19 text
Tecnologías SOA
WSDL
Create a description of your services and
its types described in XML.
Slide 20
Slide 20 text
WSDL is an XML format for describing network services as a set of
endpoints operating on messages containing either document-oriented or
procedure-oriented information.
http://ws.redpack.com.mx/RedpackAPI_WS/services/RedpackWS?wsdl
Tecnologías SOA: WSDL.
Slide 21
Slide 21 text
Tecnologías SOA: WSDL.
Slide 22
Slide 22 text
Tecnologías SOA: WSDL.
Slide 23
Slide 23 text
Tecnologías SOA: WSDL.
WSDL code generation
Slide 24
Slide 24 text
Tecnologías SOA
UDDI
Create a directory of your services
Slide 25
Slide 25 text
Tecnologías SOA: UDDI.
Slide 26
Slide 26 text
Tecnologías SOA: UDDI.
Slide 27
Slide 27 text
Tecnologías SOA: UDDI.
Slide 28
Slide 28 text
REST
Porque hacer SOA es muy complejo
Slide 29
Slide 29 text
“Representational State Transfer (REST) architectural style for distributed
hypermedia systems, describing the software engineering principles
guiding REST and the interaction constraints chosen to retain those
principles.”[1]
Hypermedia, an extension of the term hypertext, is a nonlinear medium of
information that includes graphics, audio, video, plain text and hyperlinks.
Simplemente usa HTTP y mapea los métodos de HTTP a estados.
REST
Fielding, R. T., & Taylor, R. N. (2000). Architectural styles and the design of network-based
software architectures. Doctoral dissertation: University of California, Irvine.
Slide 30
Slide 30 text
Client-Server: Separation of concerns is the principle behind the client-server constraints.
Stateless Session: state is therefore kept entirely on the client.
Cache constraints to form the client-cache-stateless-server style.
Uniform Interface (central feature). The REST interface is designed to be efficient for large-grain
hypermedia data transfer, optimizing for the common case of the Web, but not optimal for other
forms of architectural interaction.
Layered System style allows an architecture to be composed of hierarchical layers by
constraining component behavior such that each component cannot "see" beyond the
immediate layer with which they are interacting
Code-on-demand REST allows client functionality to be extended by downloading and
executing code in the form of applets or scripts. This simplifies clients by reducing the number of
features required to be pre-implemented.
REST architecture derivation
Fielding, R. T., & Taylor, R. N. (2000). Architectural styles and the design of network-based
software architectures. Doctoral dissertation: University of California, Irvine.
Slide 31
Slide 31 text
Swagger.io
Para hacer más fácil la creación de servicios REST
Slide 32
Slide 32 text
REST: Swagger.io
https://swagger.io/
Slide 33
Slide 33 text
https://swagger.io/
REST: Swagger.io
Slide 34
Slide 34 text
REST: Swagger.io
https://swagger.io/
Slide 35
Slide 35 text
Proyecto:
https://github.com/swagger-api/swagger-codegen
Generadores de código:
Swagger.io
●API clients: ActionScript, Ada, Apex, Bash, C# (.net 2.0, 4.0 or later), C++ (cpprest, Qt5, Tizen), Clojure, Dart,
Elixir, Eiffel, Erlang, Go, Groovy, Haskell (http-client, Servant), Java (Jersey1.x, Jersey2.x, OkHttp, Retrofit1.x,
Retrofit2.x, Feign, RestTemplate, RESTEasy, Vertx, Google API Client Library for Java), Kotlin, Lua, Node.js (ES5, ES6,
AngularJS with Google Closure Compiler annotations) Objective-C, Perl, PHP, PowerShell, Python, R, Ruby, Rust, Scala
(akka, http4s, swagger-async-httpclient), Swift (2.x, 3.x, 4.x), Typescript (Angular1.x, Angular2.x, Fetch, jQuery,
Node)
●Server stubs: C# (ASP.NET Core, NancyFx), C++ (Pistache, Restbed), Erlang, Go, Haskell (Servant), Java(MSF4J, Spring,
Undertow, JAX-RS: CDI, CXF, Inflector, RestEasy, Play Framework), PHP (Lumen, Slim, Silex, Symfony, Zend Expressive),
Python (Flask), NodeJS, Ruby (Sinatra, Rails5), Rust, Scala (Finch, Lagom, Scalatra)
Slide 36
Slide 36 text
GraphQL
Un lenguaje de consulta de información
Slide 37
Slide 37 text
Design Consideration
1. Data-fetching API powerful enough to describe all of Facebook
2. yet simple enough to be easy to learn and use by our product
developers.
GraphQL is a query language designed to build client applications by
providing an intuitive and flexible syntax and system for describing their
data requirements and interactions.
GraphQL is a query language
Slide 38
Slide 38 text
GraphQL is a query language
Slide 39
Slide 39 text
GraphQL
Slide 40
Slide 40 text
GraphQL
Slide 41
Slide 41 text
GraphQL: ventajas
Ventajas
● Simplifica la lógica: no hay que consultar varios endpoints para
obtener la información que necesitas.
● Toda tu información en el mismo lugar.
● No tienes que lidiar con versiones de una API.
● Puedes confiar en los tipos de dato (GraphQL describe tipos).
Desventajas
● No hay cache
Antipatrón
● Tener múltiples instancias de GraphQL.
Slide 42
Slide 42 text
Conclusiones
● Todo en la vida tiene un trade-off.
● Si necesitas una interfaz simple para clientes variados es preferible privilegiar
los datos y GraphQL es un lenguaje para eso.
● El hypermedia se sirve muy bien por REST (Objetos con su estado).
● La generación de código de SOA era buena, pero repetitiva en los clientes. Para
eso existe WSDL o Swagger que generan los clientes en automático.
● Una nueva generación de Computo de servicios está renovando SOA.
○ Microservicios (ver http://www.opengroup.org/).
○ En desarrollo continuo => Google Scholar keyword: “Microservices”
● Casi todo en el Internet es un servicio, este modelo de cómputo privilegia el
acceso fácil a usuarios finales. También composición e integración de sistemas.
Ahí reside la vigencia de SOA.
Slide 43
Slide 43 text
Conclusiones
Think about it:
Desarrollar SOA != Desarrollar con Java
Slide 44
Slide 44 text
www.codersmexico.com
www.scala.org.mx/scala_school
Donde trabajo:
webeng.kaist.ac.kr
Slide 45
Slide 45 text
@noe_dgz
noedominguez.com