Advanced Rails Recipes
Mike Clark and the Rails Commun i t y
The Pragmatic Bookshelf
Raleigh, North Carolina Dallas, Texas
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Copyright
©
2008 Mike Clark.
All rights reserved.
No part of this publication may be reproduced, stored in a retrieval system, or tran smit-
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Printed in the United States of America.
ISBN-10: 0-9787392-2-1
ISBN-13: 978-0-9787392-2-5
Printed on acid-free paper with 50% recycled, 15% post-consumer content.
Contents
1 Introduction 8
1.1 What Makes a Good Recipe Book? . . . . . . . . . . . . 8
1.2 What Makes This an Advanced Recipe Book? . . . . . . 9
1.3 Who’s It For? . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.4 Who’s Talking? . . . . . . . . . . . . . . . . . . . . . . . 10
1.5 What Version Do You Need? . . . . . . . . . . . . . . . . 10
1.6 Resources . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.7 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 11
1.8 Tags and Thumb Tabs . . . . . . . . . . . . . . . . . . . 12
Part I—REST and Routes Recipes 13
1. Create a RESTful Resource . . . . . . . . . . . . . . . . 14
2. Add Your Own RESTful Actions . . . . . . . . . . . . . . 20
3. Nest Resources to Scope Access . . . . . . . . . . . . . . 24
4. Toggle Attributes with Ajax . . . . . . . . . . . . . . . . 30
5. Authenticate REST Clients . . . . . . . . . . . . . . . . . 33
6. Respond to Custom Formats . . . . . . . . . . . . . . . 39
7. Catch All 404s . . . . . . . . . . . . . . . . . . . . . . . . 43
Part II—Database Recipes 46
8. Add Foreign Key Constraints . . . . . . . . . . . . . . . 47
9. Write Custom Validations . . . . . . . . . . . . . . . . . 51
10. Take Advantage of Master/Slave Databases . . . . . . . 54
11. Siphon Off SQL Queries . . . . . . . . . . . . . . . . . . 57
12. Use Fixtures for Canned Datasets . . . . . . . . . . . . 61
Part III—User-Interface Recipes 64
13. Handle Multiple Models in One Form . . . . . . . . . . 65
14. Replace In-View Raw JavaScript . . . . . . . . . . . . . 72
15. Validate Required Form Fields Inline . . . . . . . . . . . 74
16. Create Multistep Wizards . . . . . . . . . . . . . . . . . 78
CONTENTS 5
17. Customize Error Messages . . . . . . . . . . . . . . . . . 87
18. Upload Images with Thumbnails . . . . . . . . . . . . . 89
19. Decouple JavaScript with Low Pro . . . . . . . . . . . . 99
20. Format Dates and Times . . . . . . . . . . . . . . . . . . 106
21. Support an iPhone Interface . . . . . . . . . . . . . . . . 109
Part IV—Search Recipes 115
22. Improve SEO with Dynamic Metatags . . . . . . . . . . 116
23. Build a Site Map . . . . . . . . . . . . . . . . . . . . . . . 119
24. Find Stuff (Quick and Dirty) . . . . . . . . . . . . . . . . 124
25. Search Text with Ferret . . . . . . . . . . . . . . . . . . 127
26. Ultra-Sear ch with Sphinx . . . . . . . . . . . . . . . . . 132
27. Solr-Power Your Search . . . . . . . . . . . . . . . . . . 140
Part V—Design Recipes 151
28. Freshen Up Your Models w i th Scope . . . . . . . . . . . 152
29. Create Meaningful Relationships Through Proxies . . . 157
30. Keep Forms DRY and Flexible . . . . . . . . . . . . . . . 160
31. Prevent Train Wrecks . . . . . . . . . . . . . . . . . . . . 166
32. Simplify Controllers with a Presenter . . . . . . . . . . . 169
Part VI—Integration Recipes 174
33. Process Credit Card Payments . . . . . . . . . . . . . . 175
34. Play Nice with Facebook . . . . . . . . . . . . . . . . . . 187
35. Mark Locations on a Google Map . . . . . . . . . . . . . 189
36. Tunnel Back to Your Application . . . . . . . . . . . . . 196
Part VII—Console Snacks 200
37. Write Console Methods . . . . . . . . . . . . . . . . . . . 201
38. Log to the Console . . . . . . . . . . . . . . . . . . . . . . 203
39. Play in the Sandbox . . . . . . . . . . . . . . . . . . . . . 205
40. Access Helpers . . . . . . . . . . . . . . . . . . . . . . . . 206
41. Shortcut the Console . . . . . . . . . . . . . . . . . . . . 207
Part VIII—Asynchronous-Processing Recipes 209
42. Send Lightweight Messages . . . . . . . . . . . . . . . . 210
43. Off-Load Long-Running Tasks to BackgrounDRb . . . . 214
44. Process Asynchronous, State-Based Workflows . . . . . 222
