[esailija]

It does work for any library that uses callbacks - a node library that uses callbacks but not the node js callback convention has a bug.

1) There is not much work in promisifying libraries, for example the entire redis library can be promisified using 2 lines:

    var Promise = require("bluebird");
    var redis = require("redis");
    Promise.promisifyAll(redis.RedisClient.prototype);
    Promise.promisifyAll(redis.Multi.prototype);

After those lines all redis client objects have promise-returning versions of the methods. E.g. `redisClient.getAsync()` is the promise-returning version of `redisClient.get()`

2) Mixing callbacks and promises will result in very ugly code, see 1) to avoid it.

3) Forget about .fail(), this is not how promise error handling works. Use `.catch()` like you would use try catch. In your case that means not using it at all - then a full stack trace is automatically logged. Try catch is meant to be used with expected errors like file not existing, not bugs.