Rails 5 个参数，对象具有空数组，因为值被删除
Rails 5 params with object having empty arrays as values are dropped
我在发送如下所示的控制器参数时遇到问题：
{ id: "1", stuff: {"A" => [], "B" => [], "C" => [], "D" => []} }
该方法只看到 { id: "1" } 并且删除了整个 stuff 参数。
如果数组中有任何值，这可以更改。但是假设除了键 "C" 之外的所有数组中都有值，除了 "C" 之外它们都会存在，例如：
{ id: "1", stuff: {"A" => ["1"], "B" => ["2", "3"], "D" => ["4"]} }
我从 Rails 4.2.x -> 5.0.0 升级时遇到了这个问题
对这里发生的事情有什么建议吗？我在 munging parameters 周围看到了一些 articles/issues，但我不确定这是否是问题所在，因为在他们的例子中，table 的 munging 工作方式是 {person: []} 变成 {person: nil}，其中 person 参数没有完全删除。
来自 GH 社区的@sgrif：
This is the expected behavior. There is no way to encode an empty
array using an HTML form (e.g. Content-Type: url-form-encoded). The
reason your tests passed in Rails 4.2 is because controller tests did
not encode their parameters, they simply passed the hash through
directly. In Rails 5 it encodes them. If your controller cares about
empty arrays, it's likely that you are dealing with JSON requests. You
can do that in your test with as: :json. If you're just dealing with
form input, you will never receive an empty array.
添加 as: :json 最终对我不起作用，但在测试开始时添加 @request.headers["Content-Type"] = 'application/json' 确实有效。
我在发送如下所示的控制器参数时遇到问题：
{ id: "1", stuff: {"A" => [], "B" => [], "C" => [], "D" => []} }
该方法只看到 { id: "1" } 并且删除了整个 stuff 参数。
如果数组中有任何值，这可以更改。但是假设除了键 "C" 之外的所有数组中都有值，除了 "C" 之外它们都会存在，例如：
{ id: "1", stuff: {"A" => ["1"], "B" => ["2", "3"], "D" => ["4"]} }
我从 Rails 4.2.x -> 5.0.0 升级时遇到了这个问题
对这里发生的事情有什么建议吗？我在 munging parameters 周围看到了一些 articles/issues，但我不确定这是否是问题所在，因为在他们的例子中，table 的 munging 工作方式是 {person: []} 变成 {person: nil}，其中 person 参数没有完全删除。
来自 GH 社区的@sgrif：
This is the expected behavior. There is no way to encode an empty array using an HTML form (e.g. Content-Type: url-form-encoded). The reason your tests passed in Rails 4.2 is because controller tests did not encode their parameters, they simply passed the hash through directly. In Rails 5 it encodes them. If your controller cares about empty arrays, it's likely that you are dealing with JSON requests. You can do that in your test with as: :json. If you're just dealing with form input, you will never receive an empty array.
添加 as: :json 最终对我不起作用，但在测试开始时添加 @request.headers["Content-Type"] = 'application/json' 确实有效。