Write Schema to file using Graphql16.x

[jmtt89]

Creating file with schema on v15.x its very easy

async function buildSchema() {
    await fs.ensureFile('../graphql/schema.graphql.json')
    await fs.ensureFile('../graphql/schema.graphql')

    fs.writeFileSync(path.join(__dirname, '../graphql/schema.graphql.json'), JSON.stringify(await graphql(Schema, introspectionQuery), null, 2))
    fs.writeFileSync(path.join(__dirname, '../graphql/schema.graphql'), printSchema(Schema))
}

but on Graphql16.x return Error: Expected undefined to be a GraphQL schema.

I think is because has dropped the positional argumets

//node_modules/graphql/graphql.js
  // Temporary for v15 to v16 migration. Remove in v17
  arguments.length < 2 ||
    (0, _devAssert.devAssert)(
      false,
      'graphql@16 dropped long-deprecated support for positional arguments, please pass an object instead.',
    );
  const {
    schema,
    source,
    rootValue,
    contextValue,
    variableValues,
    operationName,
    fieldResolver,
    typeResolver,
  } = args; // Validate Schema

i try to add a object with schema await graphql({schema: Schema}) its fails with this error

{
  errors: [
    Error: Body must be a string. Received: undefined.
        at devAssert (/home/jtorres/gitrep/template-manager/node_modules/graphql/jsutils/devAssert.js:12:11)
        at new Source (/home/jtorres/gitrep/template-manager/node_modules/graphql/language/source.js:32:32)
        at new Parser (/home/jtorres/gitrep/template-manager/node_modules/graphql/language/parser.js:98:9)
        at parse (/home/jtorres/gitrep/template-manager/node_modules/graphql/language/parser.js:31:18)
        at graphqlImpl (/home/jtorres/gitrep/template-manager/node_modules/graphql/graphql.js:71:34)
        at graphqlSync (/home/jtorres/gitrep/template-manager/node_modules/graphql/graphql.js:33:18)
        at buildSchema (/home/jtorres/gitrep/template-manager/scripts/buildSchema.js:14:17)
        at async run (/home/jtorres/gitrep/template-manager/scripts/buildSchema.js:29:5)
  ]
}

maybe it's because I'm missing the introspectionQuery, but i don't know in what property I need to put it

[n1ru4l]

The source property value is what you are looking for

[jmtt89]

using source property

    fs.writeFileSync(
        path.join(__dirname, '../graphql/schema.graphql.json'),
        JSON.stringify(await graphql({ schema: Schema, source: introspectionQuery }), null, 2)
    )

The result writed on schema.graphql.json is

{
  "errors": [
    {}
  ]
}