graphql - graphql 使用空字符串值改变对象

Question

我正在尝试使用来改变 graphql 查询vue-apollo

let fields = [
  { name: 'A', value: '0' },
  { name: 'B', value: '' }
]
this.$apollo
  .mutate({
    mutation: gql`
      mutation($serve: Int!, $fields: [ComponentInput]) {
        visitCreate(serve: $serve, fields: $fields) {
          id
          ...
        }
      }
    `,
    variables: {
      serve: this.serve.id,
      fields: fields
    }
  })

但出现以下错误：

Variable "$fields" got invalid value [{"name":"A","value":"0"},{"name":"B","value":null}]; Expected non-nullable type String! not to be null at value[1].value

实际上fields应该是[{"name":"A","value":"0"},{"name":"B","value":""}]，我不知道如何。

我也试过JSON.stringify(fields)

请有任何帮助