GraphQL with RESTful returning empty response

I am connecting GraphQL with REST endpoints, I confirmed that whenever I am calling http://localhost:3001/graphql it is hitting my REST endpoint and returning JSON response. But I am getting the empty response from GraphQL server in GUI as follows:

GraphQL

REST

http://localhost:3001/graphql

REST

JSON

GraphQL

GUI


"data":
"merchant":
"id": null





Query (decoded manually):

http://localhost:3001/graphql?query=
merchant(id: 1)
id




Below is how my GraphQLObjectType looks like:

GraphQLObjectType

const MerchantType = new GraphQLObjectType(
name: 'Merchant',
description: 'Merchant details',
fields : () => (
id :
type: GraphQLString // ,
// resolve: merchant => merchant.id
,
email: type: GraphQLString, // same name as field in REST response, so resolver is not requested
mobile: type: GraphQLString
)
);


const QueryType = new GraphQLObjectType(
name: 'Query',
description: 'The root of all... queries',
fields: () => (
merchant:
type: merchant.MerchantType,
args:
id: type: new GraphQLNonNull(GraphQLID),
,
resolve: (root, args) => rest.fetchResponseByURL(`merchant/$args.id/`)
,
),
);


Response from REST endpoint (I also tried with single object in JSON instead of JSON array):

REST

[

"merchant":
"id": "1",
"email": "a@b.com",
"mobile": "1234567890"


]


REST call using node-fetch

node-fetch

function fetchResponseByURL(relativeURL)

return fetch(`$config.BASE_URL$relativeURL`,
method: 'GET',
headers:
Accept: 'application/json',

)
.then(response =>
if (response.ok)
return response.json();

)
.catch(error => console.log('request failed', error); );



const rest =
fetchResponseByURL


export default rest


GitHub: https://github.com/vishrantgupta/graphql

JSON endpoint (dummy): https://api.myjson.com/bins/8lwqk

Edit: Adding node.js tag, may be issue with promise object.

node.js

rest

resolve: (root, args) => rest.fetchResponseByURL(

)

export default rest

fetch

fetchResponseByURL

2 Answers
2

Your fetchResponseByURL function get empty string.

I think the main problem is that you are using wrong function to get the your JSON string, please try to install request-promise and use it to get your JSON string.

https://github.com/request/request-promise#readme

something like

var rp = require('request-promise');
function fetchResponseByURL(relativeURL)
return rp('https://api.myjson.com/bins/8lwqk')
.then((html) =>
const data = JSON.parse(html)
return data.merchant
)
.catch((err) => console.error(err));
// .catch(error => console.log('request failed', error); );




request-promise

Content-Type application/json

In this case using data.merchant solved my problem. But the above suggested solution i.e., use of JSON.parse(...) might not be the best practice because if there are no object in JSON, then expected response might be as follows:

data.merchant

JSON.parse(...)


"data":
"merchant": null




Instead of fields to be null.

null


"data":
"merchant":
"id": null // even though merchant is null in JSON,
// I am getting a merchant object in response from GraphQL





I have updated my GitHub: https://github.com/vishrantgupta/graphql with working code.

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