Create global error logger in GeoFireUtils

[jwngr]

With a lot of other Firebase libraries, errors begin with the name of the library, such as "Firebase Simple Login: error message." We should adopt this practice for GeoFire. It will probably be easiest to just make a utility method logError(message) which appends to "GeoFire:" to the error message.

[mikepugh]

It'd be useful for libraries to adopt a standard error format. Typically when I'm writing my apps, I'll have a central location setup to handle exceptions and they could come from any number of external libraries. It'd be nice to have a way to identify the library the exception came from, and then a code to indicate the error. Having to rely on hard coded error strings like "GeoFire: Remove key failed" are prone to mistakes since those strings often change or can get fat fingered on my end.

If instead you threw an object that looked something like:

{
    lib: "GeoFire",
    code: 1000,
    msg: "Remove key failed"
    stack: {..stack trace...},
    data: { some: 'relevant', data: 'here', when: 'applicable' }
}

An object like that along with publishing a set of error codes with the documentation, would make it slightly easier to parse and less prone to error (for example, if I bower update and don't notice that you started adding "GeoFire: " to the beginning of your errors).

// Internal library function for throwing errors
function logError(code, message, data) {
    var err = new Error();
    throw {
        lib: "GeoFire",
        code: code || -1,
        msg: message,
        data: data,
        stack: err.stack
    };
}

// example failure on removing
logError(1000, 'Remove key failed', {key: 'abcdefg'});

Now I could listen for that error somewhere in my app and either respond somehow, or at least log it to some service of mine (a la Sentry) with useful contextual data.

[jwngr]

Hey @mikepugh - sorry, I thought I had responded to this. Thanks for the suggestion! I'm going to bring this up with the whole team and see if we can come up with a common error format for all of our libraries. I'll keep you posted.

[jwngr]

I don't think I ever really got buy-in from the rest of the team on doing this across all of our repos, so I'm closing this. Maybe we will revisit it someday...