How can I handle SQLITE_CANTOPEN? - node.js

Question

I use SQLite with Node.js. If an SQLITE_CANTOPEN error occurs, I want to feedback a message to the user like "Please contact your system administrator.", but I cannot do so because an uncaughtException event will occur if SQLITE_CANTOPEN occurs actually.
How can I return to the caller after an SQLITE_CANTOPEN occurs?
const sqlite3 = require('sqlite3').verbose();
const db = new sqlite3.Database('./sample.db', sqlite3.OPEN_READONLY, err => {
// Comes here when we run db.all() below.
if (err) {
// If opening sample.db fails, SQLITE_CANTOPEN is set to err here,
// and below raise uncaughtException event.
throw err;
}
});
const promise = new Promise(
(resolve, reject) => {
db.all('SELECT userId, userName From user;', (err, rows) => {
if (err) reject(err);
else resolve(rows);
});
}
);
promise.then(value => {
// Perform the normal process.
}, err => {
// SQLITE_CANTOPEN can't catch here.
return 'Please contact your system administrator.';
});

Answer 1

I solved. By wrapping "new sqlite3.Database()" in a Promise, I was able to handle SQL_CANTOPEN before the SQL is executed.
const sqlite3 = require('sqlite3').verbose();
const openDBPromise = new Promise(
(resolve, reject) => {
const db = new sqlite3.Database('./sample.db', sqlite3.OPEN_READONLY, err => {
if (err) reject(err);
else resolve(db);
});
}
);
let db;
try {
db = await openDBPromise;
} catch (err) {
// SQLITE_CANTOPEN can handle here!
return 'Please contact your system administrator.';
}
// Perform the normal process.