express-graphql does not provide an export named 'default'

[peebles]

Using your simple example of a server, which includes a line that looks like

import expressGraphql from "express-graphql";

Throws an error. You can see this using the repl:

$ node -r esm
Welcome to Node.js v12.12.0.
Type ".help" for more information.
> import expressGraphql from "express-graphql";
Thrown:
/Users/peebles/zhortech/graphql/node_modules/esm/esm.js:1
SyntaxError: The requested module 'file:///Users/peebles/zhortech/zql/node_modules/express-graphql/index.js' does not provide an export named 'default'
> 

   "express-graphql": "^0.12.0",

[arackaf]

Hm thanks - I’ll have a look

[peebles]

My "fix" for this in in main.js:

const { graphqlHTTP } = require('express-graphql');

and

app.use( "/graphql", graphqlHTTP({ schema: executableSchema, graphiql: true, rootValue: root }) );

[arackaf]

Cool - I'll have a look at this soon. Thanks for raising this.

[arackaf]

Hey so this one is interesting. It looks like you're using Node's native esm, which is causing the failure. My code assumes you're using the esm package off of npm (which will work). What's interesting is that none of my generated code here will work with Node's native esm - it all assumes you're using the esm package.

If you can't / don't want to use the esm package off of npm, then using require for express-graphql here would absolutely be the correct fix, but like I said you'll have a lot of trouble getting all the generated graphql code to work.

I'll look at making this clearer in the docs.

[peebles]

I am a "require" kind of old-timer. I am using node 12.12. I believe I am using the esm package:

$ ls node_modules/esm/
LICENSE     README.md   esm     esm.js      index.js    node_modules    package.json

and

$ cat index.js
require = require("esm")(module/* , options */)
module.exports = require("./main.js")

and:

$ node main.js
/Users/peebles/zhortech/zql/main.js:1
import { MongoClient } from "mongodb";
^^^^^^

SyntaxError: Cannot use import statement outside a module

[arackaf]

@peebles in your example above, I believe you want

$ node index.js