Define graphQLSchema properly in Node.js - facebook-graph-api

Question

Doing graphQL first time.I searched for resources but could not found a helpful one.
I have written the following schema, got some help from another stackoverflow post.
schema.js
function getDataFromUrl(){
return [
{
"EventCode": "ET00029280",
"EventType": "CT",
"EventTitle": "OYSTERS Beach Park",
"VenueName": "Newexcelsior",
"VenueRegion": "Mumbai"
},
{
"EventCode": "ET00030629",
"EventType": "CT",
"EventTitle": "Stand-Up Comedy: The Trial Room",
"VenueName": "Newexcelsior",
"VenueRegion": "Mumbai"
}
];
}
const eventType = new GraphQLObjectType({
name: 'Event',
fields: {
EventTitle: {
type: GraphQLString,
description: 'Event Title'
},
},
});
const eventListType = new GraphQLObjectType({
name: 'EventList',
fields: {
events: {
type: new GraphQLList(eventType),
description: 'List of items',
},
},
});
const schema = new GraphQLSchema({
query: new GraphQLObjectType({
name: 'Query',
fields: {
eventList: {
type: new GraphQLList(eventListType),
resolve: () => getDataFromUrl(),
}
}
})
});
module.exports = schema;
When I query
{
eventList {
events {
EventTitle
}
}
}
I get this response:
{
"data": {
"eventList": [
{
"events": null
},
{
"events": null
}
]
}
}
I am expecting some changes in my schema, however my desired response is
{
"data": [
{
"EventTitle": "OYSTERS Beach Park"
},
{
"EventTitle": "Stand-Up Comedy: The Trial Room"
}
]
}
Please also suggest some links where I learn basics.

Answer 1

It looks like what's tripping you up the most right now is how you're defining a list. There's no need to define a separate type called EventList -- when you specify GraphQLList(someOtherType) you are already telling GraphQL to expect an array of that particular type. Your current Schema is expecting an array of an array of types. Because the structure of the data you're passing in doesn't match your schema, GraphQL can't find a field called EventTitle to match against and so it's returning null.
The fix in this case is to just get rid of eventListType altogether and change the type of your eventList field to eventType instead.
The docs for GraphQL.js are probably going to be your best bet as far as learning the basics. The only problem is the examples they include are way too basic. Here is a list of projects on GitHub that you can checkout to see GraphQL in action.
If you are starting out, I would also highly recommend using Apollo's graphql-tools. Even if you don't use Apollo on the client-side, graphql-tools makes it ridiculously easy to set up the server. Your schema would be much more readable, since you would write it as string rather than an object like you do in vanilla GraphQL.js. And you can easily set up a GraphiQL endpoint in addition to your GraphQL one, which makes debugging much easier :)