Web services

Question 1

web service = (by W3C)

Answer 1

a software application. identified by a URL, whose interfaces and binding are capable of being defined, described and discovered by XML artifacts and supports direct interactions with other software applications using XML based messages.

Question 2

characteristics of Web services:

Answer 2

• XML based everywhere
• Message-based
• Programming language independent
• Could be dynamically located
• Could be dynamically assembled or aggregated
• Accessed over the internet
• Loosely coupled
• Based on industry standards

Question 3

4 aspects that covers the SOAP specification:

Answer 3

• Message enveloppe
• Encoding rules
• RPC (Remote Procedure Call) mechanism
• RPC representation

Question 4

SOAP =

Answer 4

(Simple Object Access Protocol) It is a protocol used in software engineering for exchanging structured information in the implementation of web services. SOAP relies on XML (Extensible Markup Language) for its message format, and it typically operates over HTTP or SMTP protocols.

Question 5

encoding =

Answer 5

a set of rules of how to express application-defined data types on the wire in XML form.

Question 6

SOAP encoding, supports:

Answer 6

• simple values
• compound values

Question 7

simple values =

Answer 7

the values of built-in types from XML schema part 2 or enumeration or byte array

Question 8

compound values =

Answer 8

constructed as a composite of several parts, each with a type and can be of struct or arrays or complex type

Question 9

WSDL =

Answer 9

industry-agreed-upon XML language that can be used to describe web services.

Question 10

web service = (description)

Answer 10

A set of communication endpoints (= ports) that are capable of exchanging messages.

Question 11

Endpoint is made of 2 parts:

Answer 11

o Abstract definitions of operations and messages
o Concrete binding to networking protocol (and corresponding endpoint address) and message format

Question 12

Why WSDL?:

Answer 12

• Enables automation of communication details between communicating partners -> (machines can read WSDL, machines can invoke a service defined in WSDL)
• Discoverable through registry
• Arbitration -> (3rd party can verify if communication conforms to WSDL)

Question 13

Universal Description, Discovery and Integration (UDDI) standard = -> R.I.P.

Answer 13

Provides a mechanism for businesses to ‘describe’ themselves and the types of services they provide and then register and publish themselves in a UDDI registry. -> defines a way to publish and find information about web services

Question 14

Different types of information stored in the UDDI registry:

Answer 14

1. White pages: information about the business or organization that publishes a web service.
2. Yellow pages: information about the services themselves
3. Green pages: provide technical details about the web services listed in the Yellow Pages.

Question 15

Kinds of web services:

Answer 15

• SOAP-based web services
• RESTful Web Services
• GraphQL APIs

Question 16

API keys =

Answer 16

a key to limit access. the API key is required to send with each request.

Question 17

Integrating the Healthcare Enterprise (IHE) = (-> ! een test voor de interoperability)

Answer 17

International platform for healthcare and software providers, IT professionals, and governments to promote interoperability

Question 18

IHE solves ambiguities by

Answer 18

• specifying integration profiles
• organizing connectathons

Question 19

IHE connectathons =

Answer 19

events organized by the IHE initiative to test the interoperability and integration of healthcare IT systems based on IHE profiles and standards.

(soort evenement waarin iedereen hun systemen testen in een test omgeving. zodat ze goed werken in echte zorg. )

Question 20

Screen scraping =

Answer 20

the process of extracting data from the display output of another program or system. Like for example testing the GUI.

Question 21

disadvantage of Screen scraping:

Answer 21

• slow, takes a lot of time. Therefore the last resort solution, but sometimes the only solution.