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graphqlapollo

Date and Json in type definition for graphql


Is it possible to have a define a field as Date or JSON in my graphql schema ?

type Individual {
    id: Int
    name: String
    birthDate: Date
    token: JSON
}

actually the server is returning me an error saying :

Type "Date" not found in document.
at ASTDefinitionBuilder._resolveType (****node_modules\graphql\utilities\buildASTSchema.js:134:11)

And same error for JSON...

Any idea ?


Solution

  • Have a look at custom scalars: https://www.apollographql.com/docs/graphql-tools/scalars.html

    create a new scalar in your schema:

    scalar Date
        
    type MyType {
        created: Date
    }
    

    and create a new resolver:

    import { GraphQLScalarType } from 'graphql';
    import { Kind } from 'graphql/language';
    
    const resolverMap = {
        Date: new GraphQLScalarType({
            name: 'Date',
            description: 'Date custom scalar type',
            parseValue(value) {
                return new Date(value); // value from the client
            },
            serialize(value) {
                return value.getTime(); // value sent to the client
            },
            parseLiteral(ast) {
                if (ast.kind === Kind.INT) {
                return parseInt(ast.value, 10); // ast value is always in string format
                }
                return null;
            },
        })
    };