Metadata leak between schemas

[alx13]

Describe the bug
As said in #196 there should not be metadata leak between two schemas using different resolvers.
But currently booth schemas get same resolvers.
Actually it's related to #110 and #183, so close if you think it's duplicate.

To Reproduce
Minimal reproducible code:

// server.js
import 'reflect-metadata';
import http = require('http');
import express = require('express');
import {
  ApolloServer,
} from 'apollo-server-express';

import {
  Resolver,
  Query,
  buildSchemaSync,
} from 'type-graphql';

@Resolver()
class Schema1Resolver {
  @Query((_returns) => Boolean)
  public testSchema1() {
    return true;
  }
}

@Resolver()
class Schema2Resolver {
  @Query((_returns) => Boolean)
  public testSchema2() {
    return false;
  }
}

export async function initServer() {
  const isProduction = process.env.NODE_ENV === 'production';

  const app = express();
  const httpServer = http.createServer(app);

  new ApolloServer({
    schema: buildSchemaSync({
      resolvers: [
        Schema1Resolver,
      ],
    }),
    playground: true,
    debug: true,
    introspection: !isProduction,
    tracing: !isProduction,
  })
    .applyMiddleware({
      app,
      path: '/graphql-schema-1',
    });

  new ApolloServer({
    schema: buildSchemaSync({
      resolvers: [
        Schema2Resolver,
      ],
    }),
    playground: true,
    debug: true,
    introspection: !isProduction,
    tracing: !isProduction,
  })
    .applyMiddleware({
      app,
      path: '/graphql-schema-2',
    });

  httpServer.listen({ port: 8080 });
}

if (require.main === module) {
  initServer()
  .catch(() => {
    process.exit(1);
  });
}

Expected behavior
/graphql-schema-1 should only have testSchema1 query, and /graphql-schema-2 — testSchema2

Enviorment (please complete the following information):

• OS: MacOSX
• Node: v8.12.0
• Package version: 0.16.0
• TypeScript version: 3.2.4
• reflect-metadata: 0.1.13

[MichalLytek]

Yeah, it's a duplicate of #110 🔒

For now, you need to run two separated node.js processes:

node app-server.js
node dashbord-server.js

With separated createServer function with not imports overlap.

[johnlimed]

I was facing the same behaviour and acknowledge that the work around on v0.17.X would be to run two separate node.js scripts.

Just wanted to discuss what I found and understand whether this is similar if not the same fix that was implemented in v0.18.0-beta.1. I'm hesitant to use the beta for now.

I noticed that there was a clear function in the MetadataStorage class and so I tried to clear the storage right after a graphql schema is built.

in dist/schema/schema-generator.js line 39 I called the clear function.

    static generateFromMetadataSync(options) {
        this.checkForErrors(options);
        build_context_1.BuildContext.create(options);
        getMetadataStorage_1.getMetadataStorage().build();
        this.buildTypesInfo();
        const schema = new graphql_1.GraphQLSchema({
            query: this.buildRootQueryType(),
            mutation: this.buildRootMutationType(),
            subscription: this.buildRootSubscriptionType(),
            types: this.buildOtherTypes(),
        });
        build_context_1.BuildContext.reset();
        getMetadataStorage_1.getMetadataStorage().clear();
        return schema;
    }

This resulted in the behaviour: that each generation of schema is according to the definitions provided.

Was this the approach taken in the fix of 0.18.0-beta.1? Or are there some other considerations that I have not taken into.