Can I create a resolver with a static constructor?

[rawkode]

Is it possible to annotate a resolver to encourage type-graphql to instantiate the class with a static constructor? This would allow me to use await for loading data:

export function createYamlResolver<T extends ClassType>(
  objectTypeCls: T,
  name: string
) {
  @Resolver()
  class YamlResolver {
    protected typeName: string;
    protected typePlural: string;
    protected dataPath: string;
    protected data: T[];

    protected constructor(name: string, plural: string) {
      this.typeName = name;
      this.typePlural = plural;
    }

    public static async newWithData(): Promise<YamlResolver> {
      const schema = await getSchema();
      const schemaType = schema.getType(name) as GraphQLObjectType;

      const instance = new YamlResolver(name, schemaType.extensions.plural);

      instance.dataPath = dataDirectory + "/" + schemaType.extensions.plural;

      await instance.loadData();

      return instance;
    }

    protected async loadData() {
      const data: T[] = [];

      readdir(this.dataPath, function (err, files) {
        if (err) {
          return console.log("Unable to scan directory: " + err);
        }

        files.forEach(async function (file) {
          const filepath = join(this.dataPath, file);
          const yaml = load(await readFile(filepath, "utf8")) as T;
          // yaml.id = file.replace(".yaml", "");

          data.push(yaml);
        });
      });

      return data;
    }

    @Query((type) => [objectTypeCls], { name: `get${this.typePlural}` })
    public async getAll(): Promise<T[]> {
      return this.data;
    }
  }

  return YamlResolver;
}

Currently this doesn't work, because my constructor is protected and I'd like to encourage type-graphql to use YamlResolver::newWithData()

[MichalLytek]

Not possible. It's a bad design pattern.

[rawkode]

I'm only trying to do it this way because constructor cannot be async and because of this, the first call to the GraphQL API always returns no data.

Any advice on how I could work around that?

[MichalLytek]

Init loading data on bootstrap, wait for loading promise on every request - the first will hang for a while, the next will just go over fulfilled promise.

Or you can wait before you bootstrap the whole server while loading the data.