Five Essential tools for building REST API

Reference - http://www.essentialresttools.net/

Examples

http://websystique.com/springmvc/spring-mvc-4-restful-web-services-crud-example-resttemplate/ What exactly is REST - http://stackoverflow.com/questions/671118/what-exactly-is-restful-programming

Apigee - https://login.apigee.com/login

Collaborative Design

Use APIary Blueprint, Swagger and RAML

Testing

Use POSTMAN, cURL
SSL, Caching, DNS

HTTP

Use cURL, Burp, Fiddler, Postman, RestClient, Wireshark

Performance Testing

loader.io, biltz.io, gatling.io, jmeter Load, soak and stress testing for performance of the application

Monitoring

Logging, Instrumentation and Diagnostics

Logging into text file, database, cloud service with suitable and configurable log level.

Log rotation with size. For Logging API - you can use loggly - using KAFKA https://www.loggly.com/

Instrumentation - APM

CPU, Memory, Bandwidth(N/W In, N/W Out). Deploy/inject agent to collect the data for the analysis and report
New Relic is the tool for Instrumentation monitoring

Diagnostics

Use New Relic or Stackify to diagnose any issue wrt to the application