Firebase deploy returns unknown error - firebase

Question

I am trying to deploy my site to firebase which I have done before but now it is saying "Error: An unknown error occurred. Please contact support." The contents of the firebase-debug.log file follows:
[debug] ----------------------------------------------------------------------
[debug] Command: /usr/bin/nodejs /usr/bin/firebase deploy
[debug] Platform: linux
[debug] Node Version: v4.3.0
[debug] Time: Mon Feb 22 2016 13:58:38 GMT-0700 (MST)
[debug] ----------------------------------------------------------------------
[debug]
[debug] >>> HTTP REQUEST GET https://admin.firebase.com/firebase/joshweaverspark/token?token=XXX
[error]
[error] Error: An unknown error occurred. Please contact support.
[debug] Error Context: {
"requestOptions": {
"method": "GET",
"json": true,
"url": "https://admin.firebase.com/firebase/joshweaverspark/token?token=-KA3RgJFHuDHz6BHvFQF%7C3b00cd5fc3e1c76f43a26385a3f680c0"
},
"body": {
"error": {
"code": "UNKNOWN_ERROR",
"message": "An unknown error occurred. Please contact support."
}
},
"response": {
"statusCode": 500,
"body": {
"error": {
"code": "UNKNOWN_ERROR",
"message": "An unknown error occurred. Please contact support."
}
},
"headers": {
"server": "nginx",
"date": "Mon, 22 Feb 2016 20:58:54 GMT",
"content-type": "application/json; charset=utf-8",
"content-length": "97",
"connection": "close",
"access-control-allow-origin": "*",
"access-control-allow-methods": "GET, PUT, POST, DELETE, OPTIONS",
"x-content-type-options": "nosniff"
},
"request": {
"uri": {
"protocol": "https:",
"slashes": true,
"auth": null,
"host": "admin.firebase.com",
"port": 443,
"hostname": "admin.firebase.com",
"hash": null,
"search": "?token=-KA3RgJFHuDHz6BHvFQF%7C3b00cd5fc3e1c76f43a26385a3f680c0",
"query": "token=-KA3RgJFHuDHz6BHvFQF%7C3b00cd5fc3e1c76f43a26385a3f680c0",
"pathname": "/firebase/joshweaverspark/token",
"path": "/firebase/joshweaverspark/token?token=-KA3RgJFHuDHz6BHvFQF%7C3b00cd5fc3e1c76f43a26385a3f680c0",
"href": "https://admin.firebase.com/firebase/joshweaverspark/token?token=-KA3RgJFHuDHz6BHvFQF%7C3b00cd5fc3e1c76f43a26385a3f680c0"
},
"method": "GET",
"headers": {
"accept": "application/json"
}
}
}
}

Answer 1

After updating Node.js, i was able to deploy the project.
You can try the same by updating Node.js:
sudo npm install npm#latest -g

Answer 2

In my case upgrading node and npm wasn't enough, but upgrading firebase-tools, fixed the problem
npm install -g firebase-tools