AlecAivazis

var forwardUserID = gateway.RequestMiddleware(func(r *http.Request) error {
    // the initial context of the request is set to match the one we modified earlier

    // we are safe to extract the value we saved in context
    if userID := r.Context().Value("user-id"); userID != nil {
        // set the header with the value we pulled out of context
        r.Header.Set("USER_ID", userID.(string))
    }

    // there was no error

AlecAivazis

// add the playground endpoint to the router
http.HandleFunc("/graphql", withUserInfo(gw.PlaygroundHandler))

AlecAivazis

func withUserInfo(handler http.HandlerFunc) http.HandlerFunc {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        // look up the value of the Authorization header
        tokenValue := r.Header.Get("Authorization")

        // here is where you would perform some kind of validation on the token
        // but we're going to skip that for this example and save it as the
        // id directly. PLEASE, DO NOT DO THIS IN PRODUCTION.

        // invoke the handler with the new context

AlecAivazis

// create a reference to the hub contract we created earlier
const hub = new web3.eth.Contract(HubABI, 'hub address from earlier')

// build the list of auctions
const auctions = []
for (let i = 0; i < (await hub.methods.auctionCount().call()); i++) {
    auctions.push(new web3.eth.Contract(AuctionABI, await hub.methods.auctions(i).call()))
}

return auctions

AlecAivazis

import { makeExecutableSchema } from 'graphql-tools'

const schema = `
    type Auction {
        itemName: String!
    }

    type Query {
        allAuctions: [Auction!]!
    }

AlecAivazis

import { ApolloLink } from 'apollo-link'
import { Observable } from 'apollo-link-core'
import { graphql } from 'graphql'
import { print } from 'graphql/language/printer'
import schema from './schema'

const blockChainLink = new ApolloLink(
    (operation) => new Observable(observer => {
        graphql(schema, print(operation.query), null, null, operation.variables)
            .then(result => {

AlecAivazis

import { makeExecutableSchema } from 'graphql-tools'
import { HubABI, AuctionABI, web3 } from '../contracts'

const schema = ...

const resolvers = {
    Auction: {
        // auction is an instance of the Auction contract wrapper
        itemName: auction => auction.methods.itemName().call(),
    },

AlecAivazis

{
    allAuctions {
        offers {
            user { 
                favoritePhoto {
                    url 
                }
            }
        }
    }

AlecAivazis

node(id: $id) {
    ... on Photo {
        url
    }
}

AlecAivazis

{
    allAuctions {
        photo {
            id
        }
        user {
            username
        }
    }
}