Support schema AST as type definition

[jamiter]

TODO:

• If this PR is a new feature, reference an issue where a consensus about the design was reached (not necessary for small changes)
• Make sure all of the significant new logic is covered by tests
• Rebase your changes on master so that they can be merged easily
• Make sure all tests and linter rules pass
• Update CHANGELOG.md with your change

The webpack loader and the Meteor build plugin both return a schema AST when importing a .graphql file. It would be great to simply pass this to the makeExecutableSchema function without first having to print it.

This PR makes sure that no needless print and parsing is done when an AST is passed. If an Array is passed it will print every AST it finds so that it can be combined with passed schema strings.

See #273 (comment)

Example:

import schema from './data/schema.graphql'; // No need to print with 'graphql/language/printer'
import resolverMap from './data/resolvers';
import { makeExecutableSchema } from 'graphql-tools';

const executableSchema = makeExecutableSchema({
  typeDefs: schema,
  resolvers: resolverMap,
});

[jamiter]

Ok, coveralls is just awesome 👍

[helfer]

Thanks for the PR @jamiter! There might be a nicer way without the extra print, but I think this is good enough and a smaller change, so I'll merge it! 🙂

[jamiter]

Awesome, thanks!

[jaydenseric]

Nice! I wake up every morning with excitement to run yarn outdated to find nice little changes like this. Every day the tooling gets more elegant – thanks.

[rigobcastro]

Ok I have a question and need help for this, How can I use this on server mode? When I trying to use this great solution I catch the next error:

SyntaxError : /User/user/project/query.graphql: Unexpected token, expected

Looks easy but I don't know how to. Thanks for your support!

[chrisl777]

This fix doesn't appear to be able to handle comments in .graphql files. I see this error when I have a line that is commented out with a # character:

Unexpected character '#'

[jamiter]

@chrisl777, we should be able to add a test to check that. Could you make a PR for it? I'm a bit short on time at the moment.

[Nickersoft]

@jamiter @chrisl777 Any update on this? Does this fix actually work?

[chrisl777]

I have not had any time to check. Anyone else have a chance to play with it?

[AtomicVar]

/home/guo/git-repos/artpieces-backend/data/schema.graphql:1
(function (exports, require, module, __filename, __dirname) { scalar Datetime
                                                                     ^^^^^^^^

SyntaxError: Unexpected identifier
    at createScript (vm.js:80:10)
    at Object.runInThisContext (vm.js:139:10)
    at Module._compile (module.js:616:28)
    at Object.Module._extensions..js (module.js:663:10)
    at Module.load (module.js:565:32)
    at tryModuleLoad (module.js:505:12)
    at Function.Module._load (module.js:497:3)
    at Module.require (module.js:596:17)
    at require (internal/module.js:11:18)
    at Object.<anonymous> (/home/guo/git-repos/artpieces-backend/dist/app.js:13:15)
    at Module._compile (module.js:652:30)
    at Object.Module._extensions..js (module.js:663:10)
    at Module.load (module.js:565:32)
    at tryModuleLoad (module.js:505:12)
    at Function.Module._load (module.js:497:3)
    at Function.Module.runMain (module.js:693:10)
    at startup (bootstrap_node.js:191:16)
    at bootstrap_node.js:612:3

What's wrong with my graphql file? I think nodejs regard it as a js file.