It seems that toJSON is being called on the results of another toJSON call.

sails output

STEP 1

npm install sails@beta -g
git clone git@github.com:coinprofit/sails-model-question.git
cd sails-model-question
npm init
sails lift

STEP 2

Hit this URL in a browser:
http://localhost:1337/user/create?username=foo&password=foo&email=foo@foo.com

STEP 3

Review server output. Note that in the 2nd call, the this object in toJSON() does not contain email or password.

In toJSON { username: 'foo',
  password: 'foo',
  email: 'foo@foo.com',
  createdAt: Thu Mar 13 2014 00:58:28 GMT-0700 (PDT),
  updatedAt: Thu Mar 13 2014 00:58:28 GMT-0700 (PDT),
  id: 1 }
In toJSON { username: 'foo',
  createdAt: Thu Mar 13 2014 00:58:28 GMT-0700 (PDT),
  updatedAt: Thu Mar 13 2014 00:58:28 GMT-0700 (PDT),
  id: 1,
  avatar: 'https://secure.gravatar.com/avatar/3717483f26171b61a4e2154fb37ffbd1?s=25&r=pg&d=mm' }
error: Server Error (500)
error: TypeError: Cannot call method 'toLowerCase' of undefined
    at Object.module.exports.url (/Users/tauren/github/coinprofit/sails-model-question/node_modules/gravatar/lib/gravatar.js:10:62)
    at module.exports.attributes.gravatarImage (/Users/tauren/github/coinprofit/sails-model-question/api/models/User.js:30:23)
    at module.exports.attributes.toJSON (/Users/tauren/github/coinprofit/sails-model-question/api/models/User.js:36:26)
    at Object.stringify (native)
    at ServerResponse.res.json (/Users/tauren/github/coinprofit/sails-model-question/node_modules/sails/node_modules/express/lib/response.js:189:19)
    at created (/Users/tauren/github/coinprofit/sails-model-question/node_modules/sails/lib/hooks/blueprints/actions/create.js:71:15)
    at _normalizeCallback.callback.success (/Users/tauren/github/coinprofit/sails-model-question/node_modules/sails/node_modules/waterline/node_modules/node-switchback/lib/normalize.js:33:26)
    at _switch (/Users/tauren/github/coinprofit/sails-model-question/node_modules/sails/node_modules/waterline/node_modules/node-switchback/lib/factory.js:34:26)
    at /Users/tauren/github/coinprofit/sails-model-question/node_modules/sails/node_modules/waterline/lib/waterline/query/dql.js:106:11
    at /Users/tauren/github/coinprofit/sails-model-question/node_modules/sails/node_modules/async/lib/async.js:142:25

hi, I've encountered the same problem. Did you find a fix or a workaround? Thanks in advance.

I've got the same problem. If your user model is contained in another model, the other model should overwrite toJSON too.