強參數：如何處理嵌套的json代碼？

Question

我想寫一個處理JSON的更新方法。該JSON看起來是這樣的：

{ 
    "organization": { 
    "id": 1, 
    "nodes": [ 
     { 
     "id": 1, 
     "title": "Hello", 
     "description": "My description." 
     }, 
     { 
     "id": 101, 
     "title": "fdhgh", 
     "description": "My description." 
     } 
    ] 
    } 
} 

我的更新方法如下：

def update 
    organization = Organization.find(params[:id]) 
    nodes = params[:organization][:nodes] 
    nodes.each do |node| 
     n = Node.find(node[:id]) 
     unless n.update_attributes(node_params) 
     render json: organization, status: :failed 
     end 
    end 
    render json: diagram, status: :ok 
    end 

    private 
    def node_params 
     params.require(:organization).permit(nodes: [:title, :description]) 
    end 

不幸的是，n.update_attributes(node_params)產生：

Unpermitted parameter: id 
Unpermitted parameter: id 
Unpermitted parameter: id 
    (0.2ms) BEGIN 
    (0.3ms) ROLLBACK 
*** ActiveRecord::UnknownAttributeError Exception: unknown attribute 'nodes' for Node. 

有誰看到我做錯了什麼，並寫這個更新方法？

Answer 1

在unless n.update_attributes(node_params)線，你想用nodes_params，這些都是從你的JSON的節點減去IDS的更新節點n：

{"nodes"=>[{"title"=>"Hello", "description"=>"My description."}, {"title"=>"fdhgh", "description"=>"My description."}]}

您可以只添加:id作爲允許節點參數，刪除nodes分配步驟，改爲反覆更換node_params，並且在更新節點n時只是省略:id。例如，

def update 
    organization = Organization.find(params[:id]) 
    node_params.each do |node| 
    n = Node.find(node[:id]) 
    unless n.update_attributes(node.except(:id)) 
     render json: organization, status: :failed 
    end 
    end 
    render json: diagram, status: :ok 
end 

private 
    def node_params 
    params.require(:organization).permit(nodes: [:id, :title, :description]) 
    end