Gateway composition in GraphQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a basic gateway that composes two services.

GraphQL

const gateway = new ApolloGateway({ serviceList: [[1]] });

Drag options to blanks, or click blank then click option'

A{ name: 'users', url: 'http://localhost:4001/graphql' }, { name: 'products', url: 'http://localhost:4002/graphql' }

B'users'

C{ name: 'users', url: 'http://localhost:4001/graphql' }

D['users', 'products']

Attempts:

3 left

💡 Hint

Common Mistakes

Passing a single object instead of an array.

Using just service names as strings without URLs.

The serviceList expects an array of service definitions with name and url keys.

2fill in blank

medium

Complete the code to start the Apollo Gateway server on port 4000.

GraphQL

gateway.listen({ port: [1] }).then(({ url }) => { console.log(`Gateway ready at ${url}`); });

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A5000

B4000

C8080

D3000

Attempts:

3 left

💡 Hint

Common Mistakes

Using the port of one of the underlying services instead of the gateway port.

The gateway server is commonly started on port 4000 to avoid conflicts with underlying services.

3fill in blank

hard

Fix the error in the service list by completing the missing key.

GraphQL

const serviceList = [{ [1]: 'users', url: 'http://localhost:4001/graphql' }];

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AserviceName

Bendpoint

Cname

Dtype

Attempts:

3 left

💡 Hint

Common Mistakes

Using endpoint or serviceName instead of name.

The key name is required to identify the service in the gateway's service list.

4fill in blank

hard

Fill both blanks to create a gateway that composes two services and logs the URL when ready.

GraphQL

const gateway = new ApolloGateway({ serviceList: [1] });
gateway.listen().then(({ [2] }) => console.log(`Gateway running at ${url}`));

Drag options to blanks, or click blank then click option'

A[{ name: 'accounts', url: 'http://localhost:4003/graphql' }, { name: 'reviews', url: 'http://localhost:4004/graphql' }]

Burl

Caddress

Dendpoint

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect property names like address or endpoint.

Passing a single service object instead of an array.

The serviceList must be an array of service objects, and the listen method returns an object with a url property.

5fill in blank

hard

Fill all three blanks to define a gateway with three services and start it on port 5000.

GraphQL

const gateway = new ApolloGateway({ serviceList: [1] });
gateway.listen({ port: [2] }).then(({ [3] }) => console.log(`Gateway ready at ${url}`));

Drag options to blanks, or click blank then click option'

A[{ name: 'users', url: 'http://localhost:4001/graphql' }, { name: 'products', url: 'http://localhost:4002/graphql' }, { name: 'orders', url: 'http://localhost:4005/graphql' }]

B5000

Curl

Dendpoint

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong port numbers or property names.

Not passing an array for the service list.

The serviceList is an array of three service objects, the gateway listens on port 5000, and the listen method returns an object with a url property.