在模式中定义查询时,如何引用先前声明的GraphQLEnumType的值,将其用作参数的默认值?
假设我已经定义了以下ObservationPeriod
GraphQLEnumType:
observationPeriodEnum = new GraphQLEnumType {
name: "ObservationPeriod"
description: "One of the performance metrics observation periods"
values:
Daily:
value: '1D'
description: "Daily"
[…]
}
并将其用作查询参数period
的类型:
queryRootType = new GraphQLObjectType {
name: "QueryRoot"
description: "Query entry points to the DWH."
fields:
performance:
type: performanceType
description: "Given a portfolio EID, an observation period (defaults to YTD)
and as-of date, as well as the source performance engine,
return the matching performance metrics."
args:
period:
type: observationPeriodEnum
defaultValue: observationPeriodEnum.Daily ← how to achieve this?
[…]
}
目前我使用实际的'1D'
字符串值作为默认值;这有效:
period:
type: observationPeriodEnum
defaultValue: '1D'
但有没有办法可以使用Daily
符号名称?我找不到在架构中使用名称的方法。有没有我忽略的东西?
我问,因为我期望枚举类型也表现为一组常量,并且能够在架构定义中使用它们:
period:
type: observationPeriodEnum
defaultValue: observationPeriodEnum.Daily
天真的解决方法:
##
# Given a GraphQLEnumType instance, this macro function injects the names
# of its enum values as keys the instance itself and returns the modified
# GraphQLEnumType instance.
#
modifiedWithNameKeys = (enumType) ->
for ev in enumType.getValues()
unless enumType[ ev.name]?
enumType[ ev.name] = ev.value
else
console.warn "SCHEMA> Enum name #{ev.name} conflicts with key of same
name on GraphQLEnumType object; it won't be injected for value lookup"
enumType
observationPeriodEnum = modifiedWithNameKeys new GraphQLEnumType {
name: "description: "Daily""
values:
[…]
允许在架构定义中使用它:
period:
type: observationPeriodEnum
defaultValue: observationPeriodEnum.Daily
当然,只要枚举名称不干扰GraphQLEnumType现有方法和变量名称(当前为name
,description
,_values
,此修饰符就会满足其承诺。 },_enumConfig
,_valueLookup
,_nameLookup
,getValues
,serialize
,parseValue
,_getValueLookup
,_getNameLookup
和toString
- 请参阅https://github.com/graphql/graphql-js/blob/master/src/type/definition.js#L687中第687行的GraphQLEnumType
类定义
答案 0 :(得分:1)
我刚碰到这个。我的枚举:
const contributorArgs = Object.assign(
{},
connectionArgs, {
sort: {
type: new GraphQLEnumType({
name: 'ContributorSort',
values: {
top: { value: 0 },
},
})
},
}
);
在我的查询中,我正在做:
... on Topic {
id
contributors(first: 10, sort: 'top') {
...
}
}
原来你只是不引用该值(在考虑它之后有意义;它是枚举类型中的值,而不是实际值:
... on Topic {
id
contributors(first: 10, sort: top) {
...
}
}
答案 1 :(得分:0)
通过模式定义语言将枚举值声明为默认输入是possible,但看起来您只使用JS库API。您可以通过look at the ASTs获取工作示例来获得解决方案,并从JS代码生成的comparing that with the AST中获取解决方案。
抱歉不是解决方案,但希望有所帮助!
答案 2 :(得分:0)
我发现a pull request向枚举类型添加了一种方法.getValue()
,该方法返回了name
和value
。在您的情况下,此呼叫:
observationPeriodEnum.getValue('Daily');
将返回:
{
name: 'Daily',
value: '1D'
}