Use native BigInt type in Node 10+

[gabegorelick]

Now that Javascript has a native BigInt type, it may be time to rethink the decision to return large integers as strings.

node-pg could even fallback to a polyfill like https://www.npmjs.com/package/big-integer for older versions of Node.

[bendrucker]

Neat, didn't know about this!

big-integer and others don't seem like true polyfills to me. Even if they use BigInt internally if available, they don't return values that act like a BigInt.

So we're in a bit of an odd position where it would be nice for node 10 users to have BigInts but we can't make that backwards compatible for <10. If you upgrade your app from node 8 to 10, do the types suddenly change? I don't think that's ok. That would mean adding BigInt support as opt in, e.g. types.bigInt() auto-configures it. Happy to review a PR there.

[gabegorelick]

That would mean adding BigInt support as opt in, e.g. types.bigInt() auto-configures it.

I agree that this is the best path forward. That also makes the transition less painful if we eventually cut a new major version that dropped support for Node < 10, but that's probably a few years out.

big-integer and others don't seem like true polyfills to me. Even if they use BigInt internally if available, they don't return values that act like a BigInt.

True, but if the alternative is to use strings on Node < 10, then that's even less like BigInt. But I suppose we can leave it up to the client to decide if they want to opt in to a polyfill.

[Bessonov]

Even after reschedule EOL for Node 8, it ends this year. So, a major release with native BigInt support is reasonable for me. Also AWS Lambda supports it. That's a sign that Node 8 is really old :D

@bendrucker @brianc What do you think about drawbacks with:

import { types } from 'pg'
types.setTypeParser(20, BigInt)

?

[bendrucker]

pg currently supports node 4. I think it’s reasonable to track LTS but I’d like to do that by project policy rather than evaluating on a per-release basis. Please open an issue about that on the main pg repo and we can discuss and document accordingly.

[brianc]

I try to keep pg supporting any LTS release which is still in its support window. Looks like I could drop support for node 4 and node 6 as they've both left the LTS window.

[vitaly-t]

B.T.W. I'm dropping pre-ES2017 support right now.

[vitaly-t]

I have done some research in this area, as I am currently adding support of BigInt within pg-promise, see this issue.

First of all, since BigInt support was officially added in Node.js v10.4.0, it is simply too new to be breaking compatibility with so many clients out there. I'd say, we should give it another couple years at least, before considering such a change. I'm currently supporting Node.js v7.6.0 as the minimum, because it was the first version that made support for async/await official, which is indeed a huge milestone, and a very important aspect when writing database client code.

And since this driver does not do its own query formatting, its support for BigInt is already there.

For regular BigInt support, you just do this:

pg.types.setTypeParser(20, BigInt); // Type Id 20 = BIGINT | BIGSERIAL

And also to get arrays of BigInt natively, you add this:

// 1016 = Type Id for arrays of BigInt values
const parseBigIntArray = pg.types.getTypeParser(1016);
pg.types.setTypeParser(1016, a => parseBigIntArray(a).map(BigInt));

And that is it, the rest should just work as it is.

[gabegorelick]

Node 8 reaches end of life on December 31, 2019. At that point all active Nodejs releases will have BigInt.

[vitaly-t]

At that point all active Nodejs releases will have BigInt.

Node.js v10.4.0 onward, actually.

Also, as per comments above, enabling BitInt support in the current driver is pretty much a no-effort. With that in view, I believe nothing needs to be done here.

[gabegorelick]

Node.js v10.4.0 onward, actually.

Yes, but I believe v10 went LTS at 10.13. I would be surprised if there were still an appreciable number of clients running an older version of v10 before the LTS. If there are, I sure hope they're getting patched!

Also, as per comments above, enabling BitInt support in the current driver is pretty much a no-effort. With that in view, I believe nothing needs to be done here.

It's fine if this issue is closed as "won't fix". But I think there is an opportunity for node-pg to change its defaults. If it were written from scratch today, I see no reason why it wouldn't default to using BigInt (ignoring the LTS debate for a moment).