Function Composition

composition.js

const Fetch = (fun, fetcher) => fun({
  get(endpoint, headers) {
    return fetch(endpoint, headers)
  },
  post(endpoint, body, headers) {
    return fetch(endpoint, { body, headers, method: 'POST' })
  }
})


const GraphQLConnection = ({ name, args, query }, cb, fetcher) =>
  Fetch(http => cb({
    fields() {
    	return { name, args, query }
    },
    connect(query) {
      return http.post('http://localhost:5000', { query })
    },
    send() {
      throw new Error('Should be implemented')
    }
  }), fetcher)

const MutationBuilder = (GraphQLSchema, fun) => {
	return fun(GraphQLSchema.fields())
}

const GraphQLMutation = props =>
  GraphQLConnection(props, graphql =>
  	MutationBuilder(graphql, mutation => ({
    	send: () => graphql.connect(mutation)
    }))
  );


const mutation = GraphQLMutation({
  name: 'postAccountDocument',
  args: { document: '' },
  query: 'query {}'
})


mutation.send().then(err => {
	return err.json()
}).then(body => {
	console.log(body)
})