问题描述
我一直在遵循AWS GraphQL CLI指南来为我的应用设置API,但是在连接时遇到了麻烦。
type Employee @model {
id: ID!
employment: [Employment!] @connection(name: "byEmployeeIDByCompanyID",fields: ["id"])
}
type Company @model {
id: ID!
employees: [Employment!] @connection(name: "byCompanyIDByDateHired",fields: ["id"])
}
type Employment @model
@key(name: "byEmployeeIDByCompanyID",fields: ["employeeID","companyID"],queryField: "employmentByEmployeeIDByCompanyID") {
id: ID!
companyID: ID!
employeeID: ID!
company: Company! @connection(fields: ["companyID"])
employee: Employee! @connection(fields: ["employeeID"])
}
当我查询员工或公司时,[就业]总是返回一个空数组。我需要编辑这些字段的解析器吗?他们应该开箱即用,不是吗?
根据我的理解,将@key与'name'和多个'fields'一起使用会在表上创建一个二级索引,并通过@connection指定该键会告诉连接使用该键而不是表的主索引。例如,在“ byEmployeeIDByCompanyID”键中,employeeID是分区键,companyID是排序键。对“ employmentByEmployeeIDByCompanyID” queryField进行查询,查询中有一个employeeID,但没有companyID,它返回给定雇员的所有就业机会,这就是我想要的,为什么连接不起作用?
解决方法
我在编辑解析器中发现了成功,因此现在就开始讨论。对于Employee.employment,我添加了:
"index": "byEmployeeIDByCompanyID",
更改为请求映射模板,并将查询更改为:
{
"expression": "#partitionKey = :partitionKey","expressionNames": {
"#partitionKey": "id"
},"expressionValues": {
":partitionKey": {
"S": "$context.source.id"
}
}
}
到
{
"expression": "#partitionKey = :partitionKey","expressionNames": {
"#partitionKey": "employeeID"
},"expressionValues": {
":partitionKey": {
"S": "$context.source.id"
}
}
}