Export DatabaseError in pg package

[golergka]

I wanted to catch errors I got from pg in order to improve my project's reporting, but found out that I needed to import pg-protocol package to get DatabaseError type.

This seems a little bit illogical: I think that if I interact with a package, it should export not only the type definitions, but also the errors it's going to throw up to me.

Another reason to do this is that now I have both node-postgres and pg-protocol in my package.json, and, for example, if I update node-postgres to a new version and forget to update pg-protocol, the actual runtime type of the DatabaseError I catch may change under me, and my code that's depending on the DatabaseError type imported from outdated pg-protocol package would silently cease to work.

I also wanted to point out that documentation seems to be a bit lacking on that regard, and doesn't mention any errors that I should be catching as a user of pg package.

If you approve such changes in principle, I would be happy to contribute PR implementing them, both re-export and docs (will create a separate issue to track docs progress).

[brianc]

so you want the main pg package to export DatabaseError? that sounds reasonable

[fabienwarniez]

I am trying to read the code property of the error object returned when something fails, how can I do that in typescript using pg? Is this what this issue is referring to? Is there a workaround in the mean time?

[cakoose]

@fabienwarniez: Right now, you can do this:

import {DatabaseError} from 'pg-protocol';

try {
    ...
} catch (err) {
    if (err instanceof DatabaseProtocol and err.code === '...') {
        ...
    }
    throw err;
}

This issue is to allow importing DatabaseError from 'pg' instead of 'pg-protocol'.