Question

我已经读完了这个问题how to permit an array with strong parameters但我无法使用params.permit来解决这种情况，来自使用rails 4.2的byebug会话：

如何提取评论参数？

(byebug) params
{"comments"=>"[{\"comment\":\"ndjsnjakldnfljkasdbfhjae\",\"date\":\"2017-07-20 17:14:38\"}]", "format"=>:json, "controller"=>"airis/observations", "action"=>"create", "id"=>"13534543543"}
(byebug) params.permit(:id)
[2017-07-20 19:14:43 +0200] [f2b3d7c8-c84a-43a5-b48f-0f634be49dc7] Unpermitted parameters: comments, format
{"id"=>"13534543543"}
(byebug) params.permit(:comments)
[2017-07-20 19:14:43 +0200] [f2b3d7c8-c84a-43a5-b48f-0f634be49dc7] Unpermitted parameters: format, id
{"comments"=>"[{\"comment\":\"ndjsnjakldnfljkasdbfhjae\",\"date\":\"2017-07-20 17:14:38\"}]"}
(byebug) params.permit(comments: [:comment, :date])
[2017-07-20 19:14:43 +0200] [f2b3d7c8-c84a-43a5-b48f-0f634be49dc7] Unpermitted parameters: format, id
{"comments"=>nil}
(byebug) params.permit(:id, comments: [:comment, :date])
[2017-07-20 19:14:43 +0200] [f2b3d7c8-c84a-43a5-b48f-0f634be49dc7] Unpermitted parameter: format
{"id"=>"13534543543", "comments"=>nil}

甚至是这样：

(byebug) params.permit( :comments => [:comment, :date])
[2017-07-20 19:14:43 +0200] [f2b3d7c8-c84a-43a5-b48f-0f634be49dc7] Unpermitted parameters: format, id
{"comments"=>nil}

Answer 1

尝试一下：

2.3.1 :034 > JSON.parse(params.permit(:comments)[:comments])
Unpermitted parameters: format, id
 => [{"comment"=>"ndjsnjakldnfljkasdbfhjae", "date"=>"2017-07-20 17:14:38"}]

params.permit(:comments)只返回＆＃34;注释＆＃34; k，v对（删除未经许可的参数，format和id）：

2.3.1 :035 > params.permit(:comments)
Unpermitted parameters: format, id
 => {"comments"=>"[{\"comment\":\"ndjsnjakldnfljkasdbfhjae\",\"date\":\"2017-07-20 17:14:38\"}]"}

params.permit(:comments)[:comments]从哈希值中选择:comments键的值：

2.3.1 :036 > params.permit(:comments)[:comments]
Unpermitted parameters: format, id
 => "[{\"comment\":\"ndjsnjakldnfljkasdbfhjae\",\"date\":\"2017-07-20 17:14:38\"}]"

JSON.parse(params.permit(:comments)[:comments])将字符串转换为适当的ruby数组。

从那里，您可以使用ruby array对象执行任意操作。

如果您同时需要:comments和:id，则只需：

params.permit(:comments, :id)
Unpermitted parameter: format
 => {"comments"=>"[{\"comment\":\"ndjsnjakldnfljkasdbfhjae\",\"date\":\"2017-07-20 17:14:38\"}]", "id"=>"13534543543"}

获取各个部分：

2.3.1 :038 > params.permit(:comments, :id)[:comments]
Unpermitted parameter: format
 => "[{\"comment\":\"ndjsnjakldnfljkasdbfhjae\",\"date\":\"2017-07-20 17:14:38\"}]"

和：

2.3.1 :039 > params.permit(:comments, :id)[:id]
Unpermitted parameter: format
 => "13534543543"

你可能想把它包装成：

def clean_params
  @clean_params ||= params.permit(:comments, :id)
end

所以你可以clean_params[:comments]和clean_params[:id]。

json数组的强参数

1 个答案: