CORS in Action: Creating and consuming cross-origin APIs

342 Pages·2014·9.27 MB·English

by  Monsur Hossain

CORS in Action: Creating and
consuming cross-origin APIs
Monsur Hossain
Copyright
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Dedication
For Haroun and Annisa
Brief Table of Contents
Copyright
Brief Table of Contents
Table of Contents
Foreword
Preface
Acknowledgments
About this Book
Author Online
About the Author
About the Cover Illustration
1. Introducing CORS
Chapter 1. The Core of CORS
Chapter 2. Making CORS requests
2. CORS on the server
Chapter 3. Handling CORS requests
Chapter 4. Handling preflight requests
Chapter 5. Cookies and response headers
Chapter 6. Best practices
3. Debugging CORS requests
Chapter 7. Debugging CORS requests
Appendix A. CORS reference
Appendix B. Configuring your environment
Appendix C. What is CSRF?
Appendix D. Other cross-origin techniques
Index
List of Figures
List of Tables
List of Listings
Table of Contents
Copyright
Brief Table of Contents
Table of Contents
Foreword
Preface
Acknowledgments
About this Book
Author Online
About the Author
About the Cover Illustration
1. Introducing CORS
Chapter 1. The Core of CORS
1.1. What is CORS?
1.2. CORS by example
1.2.1. Setting up the request
1.2.2. Sending the request
1.2.3. Processing the response
1.3. Benefits of CORS
1.3.1. Wider audience
1.3.2. Servers stay in charge
1.3.3. Flexibility
1.3.4. Easy for developers
1.3.5. Reduced maintenance overhead
1.4. Summary
Chapter 2. Making CORS requests
2.1. What is a cross-origin request?
2.2. Browser support for CORS
2.3. Using the XMLHttpRequest object
2.3.1. Sending an HTTP request
2.3.2. Handling the HTTP response
2.3.3. Including cookies on cross-origin requests
2.4. XDomainRequest object in Internet Explorer 8 and 9
2.4.1. Differences between XDomainRequest and
XMLHttpRequest
2.5. Canvas and cross-origin images
2.6. CORS requests from jQuery
2.7. Summary
2. CORS on the server
Chapter 3. Handling CORS requests
3.1. Setting up the sample code
3.1.1. Setting up the sample API
3.1.2. Setting up the sample client
3.1.3. Running the sample app
3.2. Making a CORS request
3.3. Anatomy of a CORS request
3.3.1. The players in a CORS request
3.3.2. Lifecycle of a CORS request
3.4. Making a request with the Origin header
3.4.1. Viewing the Origin header
3.4.2. What is an origin?
3.4.3. Setting the Origin header
3.5. Responding to a CORS request
3.5.1. The Access-Control-Allow-Origin header
3.5.2. Access-Control-Allow-Origin with a wildcard (*) value
3.5.3. Access-Control-Allow-Origin with an origin value
3.5.4. Rejecting CORS requests
3.6. Summary
Chapter 4. Handling preflight requests
4.1. What is a preflight request?
4.1.1. Lifecycle of a preflight request
4.1.2. Why does the preflight request exist?
4.2. Triggering a preflight request
4.2.1. When is a preflight request sent?
4.3. Identifying a preflight request
4.3.1. Origin header
4.3.2. HTTP OPTIONS method
4.3.3. Access-Control-Request-Method header
4.3.4. Putting it all together
4.4. Responding to a preflight request
4.4.1. Supporting HTTP methods with Access-Control-Allow-
Methods
4.4.2. Supporting request headers with Access-Control-Allow-
Headers
4.4.3. Sending the actual request
4.4.4. Rejecting a preflight request