[apollo-language-server] Allow config.client.service.localSchemaFile

[stnwk]

Imagine the following apollo.config.js:

module.exports = {
  client: {
    service: {
      name: 'My Application',
      localSchemaFile: './src/schema.json',
    },
  },
};

This config comes from the following situation:

• You cannot provide an api endpoint for some reasons (maybe auth, whatever)
• However, you have the necessary schema.json locally

Currently, this is not possible.
This PR fixes this.

• Fixes apollo-vscode: Cannot use local schema file #669

[stnwk]

No idea what's wrong with circleci though 🤔

[stnwk]

@martijnwalraven Can you take a look at this and give me a hint whether this is moving in the right direction? Thanks :)

[martijnwalraven]

@stnwk Yes, sorry, I had pushed a fix for the getServiceName issue before I saw this, so it needs to be rebased. (The CI issues should be fixed.)

Using FileSchemaProvider is exactly what that was meant for, but we'll need to decide on the config format. I suspect we'll want to nest localSchemaFile under service instead of directly under client, but I'd like to get @jbaxleyiii's take on that as well.

[stnwk]

@martijnwalraven @jbaxleyiii

Thanks for your input! You're right: Nesting localSchemaFile under client.service seems more accurate to me as well.

I rebased and updated my code to support the following config:

module.exports = {
  client: {
    service: {
      name: 'My Application',
      localSchemaFile: './src/schema.json',
    },
  },
};

I have also updated the README to include an example of this config and be more detailed about it.

[martijnwalraven]

Thanks, merged from 10000m altitude!

[tsaiDavid]

Thanks @stnwk - needed the localSchemaFile option, but I'm seeing the following error from my Apollo VSCode plugin's output:

(node:93814) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): TypeError: Cannot read property 'schemaTags' of null

(node:93814) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

[stnwk]

@tsaiDavid I'm not sure this is related. Can you open up a new issue with a more detailed description? Maybe also include what your schema file looks like and your full apollo.config.js