Sendgrid-nodejs: Cannot import package with TypeScript 2.5.x and 2.6.x

[ShaharHD]

Trying to import the package in a Typescript file:
import * as SendGrid from '@sendgrid/mail';

gives the following error on tsc build:

src/libs/communications.ts(1,27): error TS2497: Module '"<long path>/node_modules/@sendgrid/mail/index"' resolves to a non-module entity and cannot be imported using this construct.

Any known resolution for this issue except using the following workaround?
import SendGrid = require('@sendgrid/mail'); // tslint:disable-line

[thinkingserious]

@SPARTAN563,

Any ideas on this one? Thanks!

[duncanleung]

Hi @thinkingserious,

It looks like this SO post addresses this issue:
https://stackoverflow.com/questions/39415661/what-does-resolves-to-a-non-module-entity-and-cannot-be-imported-using-this

From what I understand...

In packages/mail/src/mail.d.ts (https://github.com/sendgrid/sendgrid-nodejs/blob/master/packages/mail/src/mail.d.ts), it looks like the export is using CommonJS export, and not ES6 export default:

//packages/mail/src/mail.d.ts  line 33
export = new MailService()

Thus, you can't use ES6 imports as the OP desired:

import * as SendGrid from '@sendgrid/mail';

Instead, he needed to use CommonJS require. It's not a 'hack'. It's just following the same convention:

import SendGrid = require('@sendgrid/mail');

[thinkingserious]

Thanks @duncanleung!

@ShaharHD,

Does that answer solve your issue?

[ShaharHD]

Not really ... as my original post actually gave the workaround which was
import SendGrid = require('@sendgrid/mail'); // tslint:disable-line

I was asking to see if there's a cleaner way of doing it as in TS the standard is to have tslint to not allow require (hence the // tslint:disable-line)

Maybe this should be included in the README.md of the repo as the workaround for using sendgrid with TypeScript?

[duncanleung]

@thinkingserious Referencing the same SO article:

"If you control both modules, you can use export default instead"
https://stackoverflow.com/questions/39415661/what-does-resolves-to-a-non-module-entity-and-cannot-be-imported-using-this

The long-term fix and action item here, is to rewrite any CommonJS export = to use the ES6 export default in the sendgrid-nodejs lib

If you agree / approve that this is the correct solution, I'd like to take a stab at the fix.

Please advise. Thanks!

[thinkingserious]

Thanks @ShaharHD,

For now, could you please add the workaround to our TROUBLESHOOTING section for hacktoberfest?

@adamreisnz, thoughts on @duncanleung's solution?

[adamreisnz]

@thinkingserious ES6 export/import syntax isn't supported yet in Node 8 last I checked, so we can't switch from requires to imports etc.

https://medium.com/the-node-js-collection/an-update-on-es6-modules-in-node-js-42c958b890c

And:

Modules should be natively available in the Node.js version 10, in about april 2018.

https://tech.io/playgrounds/5262/native-es-modules-in-node-js

[duncanleung]

@adamreisnz Oh, right =p Thanks for the feedback and links on ES6 export/import syntax in Node.

[ShaharHD]

Seems in TS 2.6.x a breaking change that requires the export of the library to be fixed

TS2714

it seems the only workaround now is to lock down TS version to 2.5.x?

[notheotherben]

@ShaharHD thanks for bringing that to our attention, I'll get a PR put together to address it quickly.

[thinkingserious]

Thank you @SPARTAN563!

[ShaharHD]

Why wasn't this included in 6.2.0?

[thinkingserious]

It should be deployed later today, @ShaharHD. Thanks!

[killtheliterate]

Somewhat related, how would I use the index.d.ts from the lib? I've tried a few different variations of the following:

import SendGrid = require('@sendgrid/mail')

export interface Foo {
  mail: Sendgrid.MailService
}

This doesn't work, nor do the variants, all resulting in either cannot find name or cannot find namespace

[thinkingserious]

Hello @killtheliterate,

Would you mind creating a new issue? Thanks!

With Best Regards,

Elmer