Using Apollo

What is Apollo?

Apollo is a popular GraphQL client for React and other platforms.

It is not necessary to use it to execute queries and mutations on ComposeDB, but it can help simplify the developer experience for common use-cases.

The ComposeDB client can be used with the Apollo client by creating a custom Apollo link, as shown in the example below:

Make sure you have the composedb packages installed, before running the code below. In this case, you'll also need @apollo/client, as well as a compiled runtime definition for your composite.

import { ApolloClient, ApolloLink, InMemoryCache, Observable } from '@apollo/client'
import { ComposeClient } from '@composedb/client'

// Path to the generated runtime composite definition
import { definition } from './__generated__/definition.js'

const compose = new ComposeClient({ ceramic: 'http://localhost:7007', definition })

// Create a custom ApolloLink using the ComposeClient instance to execute operations
const link = new ApolloLink((operation) => {
  return new Observable((observer) => {
    compose.execute(operation.query, operation.variables).then(
      (result) => {
        observer.next(result)
        observer.complete()
      },
      (error) => {
        observer.error(error)
      }
    )
  })
})

// Use the created ApolloLink instance in your ApolloClient configuration
export const client = new ApolloClient({ cache: new InMemoryCache(), link })