How can I debug a PUT request in Rails 3.1? - mysql

Question

I am developing a simple iOS app, which uses a Rails app as a server backend. I'm using the Restkit framework for the management of the server networking / requests and on the iOS side all seems to be OK.
When I make a PUT request, I get a 200 response back, and the logs in XCode seem to suggest all is well. When I look at the logs for the Rails app, it also seems to suggest all is well, with the following output:
2011-12-19T18:15:17+00:00 app[web.1]: Started PUT "/lists/3/tasks/6" for 109.156.183.65 at 2011-12-19 18:15:17 +0000
2011-12-19T18:15:17+00:00 app[web.1]: Parameters: {"created_at"=>"2011-12-12 22:37:00 +0000", "id"=>"6", "updated_at"=>"2011-12-12 22:37:00 +0000", "description"=>"Create a home page", "list_id"=>"3", "completed"=>"1"}
2011-12-19T18:15:17+00:00 app[web.1]: Task Load (4.3ms) SELECT "tasks".* FROM "tasks" WHERE "tasks"."id" = $1 LIMIT 1 [["id", "6"]]
2011-12-19T18:15:17+00:00 app[web.1]: Processing by TasksController#update as JSON
2011-12-19T18:15:17+00:00 app[web.1]: (4.7ms) BEGIN
2011-12-19T18:15:17+00:00 app[web.1]: (1.5ms) COMMIT
2011-12-19T18:15:17+00:00 app[web.1]: Completed 200 OK in 48ms (Views: 1.1ms | ActiveRecord: 16.0ms)
2011-12-19T18:15:17+00:00 heroku[nginx]: 109.156.183.65 - - [19/Dec/2011:10:15:17 -0800] "PUT /lists/3/tasks/6 HTTP/1.1" 200 154 "-" "TaskM8/1.0 CFNetwork/485.13.9 Darwin/11.2.0" taskm8.com
2011-12-19T18:15:17+00:00 heroku[router]: PUT taskm8.com/lists/3/tasks/6 dyno=web.1 queue=0 wait=0ms service=114ms status=200 bytes=154
However, when I make another get request, or use the standard web views to look at the data, the change I was expecting from the PUT request (Completed = 1 - which is a BOOL field), no change has been made.
I can see from the rails log that my iOS app is passing the correct parameters, so it seems to be something on the rails side. I've been through the loop of overcoming the CSRF error message, so don't think it's that.
On a local version of the rails app, I've also run general logging against the MySql database to monitor the queries being run, trying to see if the PUT does anything at all, or anything which would fail... in the log, you don't see anything other than:
BEGIN
COMMIT
The same as the rails log.
So, does anyone have any idea about why the PUT is not making the changes to the data, or how I can debug the PUT further?
Apologies if this is a real simple question, I'm slowly getting back into development and am somewhat rusty!

Answer 1

Are you using any kind of automated tests? If not, start there.
Another way (though rubbish) would be to call your controller action from a webpage and see if it works.
You can also add logger.debug in your rails code to add traces.

Answer 2

If you have control over the MySQL server I would suggest that you enable the general log aka the query log, that way you can see what really happens.
SET GLOBAL general_log_file = '/tmp/query.log'
SET GLOBAL general_log = 'ON';