My current project involves creating an API in nestJS using only plain expressJS and mysql, without relying on typeorm. Unfortunately, I've found very limited information in the documentation or other sources to guide me through this process.
Here's what I've completed so far:
- Established a global variable to store the connection obtained from
mysql.createConnection(). - Attempted to utilize this connection to retrieve data from the database:
async findAll() {
return await connection.query('SELECT * from test', (error, results, fields) => {
console.log(results);
return results;
});
}
The console displays the following data:
[ RowDataPacket {
id: 1,
firstName: 'test',
middleName: '1',
lastName: 'user' },
RowDataPacket {
id: 2,
firstName: 'test',
middleName: '2',
lastName: 'user' }
]
However, it's also generating the error:
TypeError: Converting circular structure to JSON
at JSON.stringify (<anonymous>)
EDIT:
To resolve this issue, I attempted a solution recommended by @Kim Kern:
return await connection.query('SELECT * from users', (error, results, fields) => {
results = results.map((result) => {
return Object.assign({}, result);
});
console.log(results);
return results;
});
Although the updated results no longer display RowDataPacket, the same error persists.