### Start Demo Client (Bash)

Source: https://github.com/oodelally/ra-data-graphql-simple-mongest-resolver/blob/master/demo-client/README.md

Navigates to the demo client directory, installs its dependencies, copies the environment file, and starts the client application.

```bash
cd ./demo-client
npm i
cp .env.example .env
pm start
```

--------------------------------

### Start Test Server (Bash)

Source: https://github.com/oodelally/ra-data-graphql-simple-mongest-resolver/blob/master/demo-client/README.md

Installs project dependencies and starts the test GraphQL server. The server playground will be available at http://localhost:1234/graphql.

```bash
npm i
npm run test-server
```

--------------------------------

### Installing Dependencies for ra-data-graphql-simple-mongest-resolver (Bash)

Source: https://github.com/oodelally/ra-data-graphql-simple-mongest-resolver/blob/master/README.md

Commands to install the necessary peer dependencies (like mongodb, mongoose, NestJS modules, Apollo) and the ra-data-graphql-simple-mongest-resolver library itself using npm.

```bash
npm install --save mongodb mongoose @nestjs/mongoose @apollo/gateway @nestjs/graphql apollo-server-core apollo-server-express graphql mongest-service
npm install --save ra-data-graphql-simple-mongest-resolver
```

--------------------------------

### Example GraphQL Query for Cats (GraphQL)

Source: https://github.com/oodelally/ra-data-graphql-simple-mongest-resolver/blob/master/README.md

An example GraphQL query demonstrating how to fetch data for 'allCats', including basic fields and fields specific to potential discriminator types ('StrayCat', 'HomeCat') using inline fragments.

```gql
query {
  allCats {
    id
    name
    ...on StrayCat {
      territorySize
    }
    ...on HomeCat {
      humanSlave
    }
  }
}
```

--------------------------------

### Generated Mongo Projection Example (JavaScript)

Source: https://github.com/oodelally/ra-data-graphql-simple-mongest-resolver/blob/master/README.md

Shows the MongoDB projection object automatically generated by the resolver based on the fields requested in the corresponding GraphQL query, ensuring only necessary fields are fetched from the database.

```js
{
  _id: true,
  name: true,
  territorySize: true,
  humanSlave: true,
  age: true
}
```

--------------------------------

### Defining Basic Entity, Service, and Resolver (TypeScript)

Source: https://github.com/oodelally/ra-data-graphql-simple-mongest-resolver/blob/master/README.md

Demonstrates the minimal setup for creating a Mongoose schema (@Schema, @Prop), registering it with Mongest (registerEntityClassForSchema), building a basic Mongest service (BuildMongestService), and creating a default ra-data-graphql-simple-compatible resolver (BuildMongestRaResolver) in NestJS.

```ts
@Schema()
export class Cat {
  _id!: ObjectId;

  @Field(() => String)
  @Prop({ required: true, type: String })
  name!: string;
}

export const CatSchema = SchemaFactory.createForClass(Cat);
registerEntityClassForSchema(Cat, CatSchema);


@Injectable()
export class CatsService extends BuildMongestService(Cat) {
  // Expandable service!
}

@Resolver(() => Cat)
export class CatsResolver extends BuildMongestRaResolver(Cat) {
  constructor(service: CatsService) {
    super(service);
  }
  // Expandable resolver!
}
```

--------------------------------

### Customizing Resolver Options and Adding Fields (TypeScript)

Source: https://github.com/oodelally/ra-data-graphql-simple-mongest-resolver/blob/master/README.md

Illustrates how to customize the generated resolver using the options object (MongestRaResolverOptions). This includes adding custom filters, defining virtual fields, specifying required fields for discriminators, configuring endpoint behavior (enabling/disabling, adding guards/interceptors, omitting arguments), and adding custom GraphQL fields using @ResolveField.

```ts
// Add any custom filter. It will be added to the `allCats` endpoint arguments.
@InputType()
class CatFilter {
  @Field(() => String, { nullable: true })
  nameRegexp?: string;
}

// Tell how the CatFilter should be translated into a mongo filter
const graphqlFilterToMongoFilter = async ({ nameRegexp }: CatFilter): Promise<FilterQuery<Cat>> => {
  // The filter builder can be synchronous or asynchronous
  const filter: FilterQuery<Cat> = {};
  if (nameRegexp) {
    filter.name = new RegExp(escapeRegExp(nameRegexp), 'i');
  }
  return filter;
};

const CatsResolverOptions: MongestRaResolverOptions<Cat, CatFilter> = {
  filter: {
    classRef: CatFilter,
    filterBuilder: graphqlFilterToMongoFilter,
  },
  virtualFields: {
    fancyName: { dependsOn: ['name'] }, // Include `name` if the virtual field `fancyName` needs it to resolve (see the resolver below).
  },
  discriminatorRequiredExtraFields: ['age'], // e.g. if `age` is required in your graphql resolveType().
  endpoints: {
    update: {
      enable: true, // By default, for safety, only the readonly endpoints are enabled.
    },
    delete: {
      enable: true,
      guard: myPermissionGuard, // Add a guard to the `delete` endpoint.
      interceptor: myLoggerInterceptor, // Add an interceptor to the `delete` endpoint.
    },
    create: {
      args: {
        omitFields: ['color'], // Dont include `color` as `create`'s argument.
      },
    },
  },
};

@Resolver(() => Cat)
export class CatsResolver extends BuildMongestRaResolver(Cat, CatsResolverOptions) {
  constructor(service: CatsService) {
    super(service);
  }

  @ResolveField(() => String)
  async fancyName(@Parent() parent: { name: string }) {
    return `Fancy ${parent.name}`;
  }

  // Add new custom endpoints here
}
```

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