Adding Firebase data, dots and forward slashes

Question

I try to use firebase db, I found very important restrictions, which are not described in firebase help or FAQ.

First problem is that symbol: dot '.' prohibited in keys,

i.e. firebase reject (with unknown reason) next:

        nameRef.child('[email protected]').set('Pirat');

Second problem with forward slashes in your keys '/', when you try to add key like this

        {'02/10/2013': true}

In firebase you can see:

         '02': {
             '10': {
                 '2013': true
             }
         }       

Have you got any ideas how to solve it (automatically)? May be set some flag that it is string key with all symbols? Of course, I can parse/restore data every time before write and after read, but...

By the way '.' '/' - all restricted symbols for firebase ?

Answer 1

The reason that adding a child 02/10/2013 creates a structure in Firebase is because the forward slashes are resulting in the creation of a new level.

So the line I assume you are using something similar to: firebaseRef.child('02/10/2013').set(true) is equivalent to firebaseRef.child('02').child('10').child('2013').set(true).

To avoid the problems of not being able to use the following characters in reference key names (source),

• . (period)
• $ (dollar sign)
• [ (left square bracket)
• ] (right square bracket)
• # (hash or pound sign)
• / (forward slash)

we can use one of JavaScript's built in encoding functions since as far as I can tell, Firebase does not provide a built in method to do so. Here's a run-through to see which is the most effective for our purposes:

var forbiddenChars = '.$[]#/'; //contains the forbidden characters
escape(forbiddenChars); //results in ".%24%5B%5D%23/"
encodeURI(forbiddenChars); //results in ".%24%5B%5D%23%2F"
encodeURIComponent(forbiddenChars); //results in ".%24%5B%5D%23%2F"

Evidently, the most effective solution is encodeURIComponent. However, it doesn't solve all our problems. The . character still poses a problem as shown by the above test and trying to encodeURIComponent your test e-mail address. My suggestion would be to chain a replace function after the encodeURIComponent to deal with the periods.

Here's what the solution would look like for your two example cases:

encodeURIComponent('[email protected]').replace(/\./g, '%2E') //results in "Henry%2EMorgan%40caribbean%2Esea"
encodeURIComponent('02/10/2013'); //results in "02%2F10%2F2013"

Since both the final results are safe for insertion into a Firebase as a key name, the only other concern is decoding after reading from a Firebase which can be solved with replace('%2E', '.') and a simple decodeURIComponent(...).