Introduction to APIs

Overview

Teaching: 25 min
Exercises: 0 min

Questions

• What are APIs? What can they do?

Objectives

• Explain how an API functions

• Explain common API types

Vocabulary

• API – Application Programming Interface
  • A set of clearly defined methods of communication between various software components. (https://en.wikipedia.org/wiki/Application_programming_interface)
• REST – REepresentational State Transfer
  • A data-driven architecture for web services reliant on HTTP
    • GET – Requests data to be returned from an online source
    • POST – Requests data to be submitted to an online source
• SOAP–Simple - Object Access Protocol
  • A protocol relying on XML structure to for requests & responses
    • Send request XML using terms specific to SOAP•Response sent in XML format
    • Can use any transport protocol, not just http
• OAuth – Open Authorization Standard

What is an API?

• Web Applications
  • Kayak or Expedia

Library-related APIs

• HathiTrust
  • Bibliographic API: https://www.hathitrust.org/bib_api
  • Data API: ttps://www.hathitrust.org/data_api
• Springer or BioMedCentral
  • 4 APIs: Sttps://dev.springer.com/
• OCLC
  • 22 APIs: https://www.oclc.org/developer/develop/web-services.en.html
  • Includes ‘Search’, ‘Metadata’, and ‘VIAF’ APIs
• Voyager API
  • 2 APIs (VoyagerSearch, VoyagerUpdate)
  • Developed by YUL Library IT (Yue Ji)
  • Actively used by Preservation Department for their project and workflow

How APIs work

How APIs work

Key Points

• APIs are used all over the web’

• APIs alllow applications to request data from web servers

• There are several types of APIs

• APIs can act as a ‘middle-man’ between you and data

• APIs can help gather bulk data & metadata from library services