【发布时间】：2017-08-08 20:24:33
【问题描述】：
我关注了the documentation about using graphql-tools to mock a GraphQL server，但是这会引发自定义类型的错误，例如：
Expected a value of type "JSON" but received: [object Object]
关于模拟的 graphql-tools 文档明确声明它们支持自定义类型，甚至提供了使用来自 graphql-type-json 项目的 GraphQLJSON 自定义类型的示例。
我提供了 a demo of a solution on github，它使用 graphql-tools 成功模拟了 GraphQL 服务器，但这依赖于猴子修补构建的架构：
// Here we Monkey-patch the schema, as otherwise it will fall back
// to the default serialize which simply returns null.
schema._typeMap.JSON._scalarConfig.serialize = () => {
return { result: 'mocking JSON monkey-patched' }
}
schema._typeMap.MyCustomScalar._scalarConfig.serialize = () => {
return mocks.MyCustomScalar()
}
可能我在演示中做错了什么，但如果没有上面的猴子补丁代码，我会收到有关上述自定义类型的错误。
有没有人有比我的演示更好的解决方案，或者任何关于我可能做错了什么的线索，以及我可以如何更改代码以使演示在没有猴子修补架构的情况下工作？
demoindex.js中的相关代码如下：
/*
** As per:
** http://dev.apollodata.com/tools/graphql-tools/mocking.html
** Note that there are references on the web to graphql-tools.mockServer,
** but these seem to be out of date.
*/
const { graphql, GraphQLScalarType } = require('graphql');
const { makeExecutableSchema, addMockFunctionsToSchema } = require('graphql-tools');
const GraphQLJSON = require('graphql-type-json');
const myCustomScalarType = new GraphQLScalarType({
name: 'MyCustomScalar',
description: 'Description of my custom scalar type',
serialize(value) {
let result;
// Implement your own behavior here by setting the 'result' variable
result = value || "I am the results of myCustomScalarType.serialize";
return result;
},
parseValue(value) {
let result;
// Implement your own behavior here by setting the 'result' variable
result = value || "I am the results of myCustomScalarType.parseValue";
return result;
},
parseLiteral(ast) {
switch (ast.kind) {
// Implement your own behavior here by returning what suits your needs
// depending on ast.kind
}
}
});
const schemaString = `
scalar MyCustomScalar
scalar JSON
type Foo {
aField: MyCustomScalar
bField: JSON
cField: String
}
type Query {
foo: Foo
}
`;
const resolverFunctions = {
Query: {
foo: {
aField: () => {
return 'I am the result of resolverFunctions.Query.foo.aField'
},
bField: () => ({ result: 'of resolverFunctions.Query.foo.bField' }),
cField: () => {
return 'I am the result of resolverFunctions.Query.foo.cField'
}
},
},
};
const mocks = {
Foo: () => ({
// aField: () => mocks.MyCustomScalar(),
// bField: () => ({ result: 'of mocks.foo.bField' }),
cField: () => {
return 'I am the result of mocks.foo.cField'
}
}),
cField: () => {
return 'mocking cField'
},
MyCustomScalar: () => {
return 'mocking MyCustomScalar'
},
JSON: () => {
return { result: 'mocking JSON'}
}
}
const query = `
{
foo {
aField
bField
cField
}
}
`;
const schema = makeExecutableSchema({
typeDefs: schemaString,
resolvers: resolverFunctions
})
addMockFunctionsToSchema({
schema,
mocks
});
// Here we Monkey-patch the schema, as otherwise it will fall back
// to the default serialize which simply returns null.
schema._typeMap.JSON._scalarConfig.serialize = () => {
return { result: 'mocking JSON monkey-patched' }
}
schema._typeMap.MyCustomScalar._scalarConfig.serialize = () => {
return mocks.MyCustomScalar()
}
graphql(schema, query).then((result) => console.log('Got result', JSON.stringify(result, null, 4)));
【问题讨论】：
-
我也看到自定义标量类型以完全相同的方式模拟失败。默认情况下，serialize 函数返回 null/没有其他人注意到这一点吗？真的有人在用这个软件吗？
标签： graphql