In node.js + sqlite3:
What is a good way to notify a caller from a callback about errors and get the caller to try again ? When we get a database locked error - would like to try and run the query again.
TestController.prototype.addDevices = function (number_of_devices, callback_after_all_devices_have_been_added) {
var controller = this;
var db = controller.connectToDb();
for(i = 0; i < number_of_devices; i++) {
db.each("SELECT api_key as ak FROM user_table ORDER BY RANDOM() LIMIT 1", function(err, row) {
//sometimes we get a SQLITE: database locked error
if (err !== null) {
console.log("Error found");
//i-- this will not work - but how do we do it then?
return;
}
console.log("Error: " + err);
//code to process if we get an entry from the user_table ..
});
}
}
This is how I managed to solve this - added a retry counter and moved the problem code to its own function, passing in the epilogue as a callback. It works - but is this a good way? (other than using promises or the async module?)