我有以下猫鼬模式:
const MessageSchema = new Schema({
author: {
account:{
type:String,
enum:['employee','admin'],
},
id: String,
}
//other fields
})
然后在我的graphql-schemas
文件中,我具有以下架构类型:
const MessageType = new GraphQLObjectType({
name: 'Message',
fields: () => ({
account: {
type: AuthorType,
//resolve method
},
id: {type: GraphQLString},
})
})
const AuthorType= new GraphQLObjectType({
name: 'Author',
fields: () => ({
account: {
type://This will either be AdminType or EmployeeType depending on the value of account in db (employee or admin),
//resolve method code goes here
}
})
})
如AuthorType
的注释中所述,我需要account
字段才能解析为Admin
或Employee
,具体取决于account
字段的值在数据库中。
如何有条件地动态确定架构中的字段类型?
答案 0 :(得分:0)
我没有立即确定类型,而是重新构建了代码,如下所示:
const MessageType = new GraphQLObjectType({
name: 'Message',
fields: () => ({
id:{type:GraphQLString},
author: {
type: AuthorType,
async resolve(parent, args) {
if (parent.author.account === 'guard') {
return await queries.findEmployeeByEmployeeId(parent.author.id).then(guard => {
return {
username: `${guard.first_name} ${guard.last_name}`,
profile_picture: guard.profile_picture
}
})
} else if (parent.author.account === 'admin') {
return {
username: 'Administrator',
profile_picture: 'default.jpg'
}
}
}
},
//other fields
})
})
const AuthorType = new GraphQLObjectType({
name: 'Author',
fields: () => ({
username: {type: GraphQLString},
profile_picture: {type: GraphQLString},
})
})
由于我从AuthorType
中需要的只是作者的用户名和个人资料图片,因此员工和管理员都具有这些字段,我将这些字段传递给AuthorType
。
在MessageType
中,我应用逻辑来确定resolve
的{{1}}方法中的帐户类型,然后从逻辑中构造自定义对象以匹配author
。