jq コマンドで json の特定のフィールドを削る・抽出する

json例

	             {
                     "response": {
                       "num": 2,
                       "object": [
                         {"id": "a1", "name": "名前1", "price": 1000, "updated_at": "2024-06-26"},
                         {"id": "b2", "name": "名前2", "price": 2000, "updated_at": "2024-06-30"}
                       ]
                     }
                  }

抽出　

// object内の配列を抽出
echo '{"response": {"num": 2,"object": [{"id": "a1", "name": "名前1", "price": 1000, "updated_at": "2024-06-26"},{"id": "b2", "name": "名前2", "price": 2000, "updated_at": "2024-06-30"}]}}' | jq '.response.object[].id'

"a1"
"b2"

// numとobjectを抽出
echo '{"response": {"num": 2,"object": [{"id": "a1", "name": "名前1", "price": 1000, "updated_at": "2024-06-26"},{"id": "b2", "name": "名前2", "price": 2000, "updated_at": "2024-06-30"}]}}' | jq '.response.object[],.response.num'

{
  "id": "a1",
  "name": "名前1",
  "price": 1000,
  "updated_at": "2024-06-26"
}
{
  "id": "b2",
  "name": "名前2",
  "price": 2000,
  "updated_at": "2024-06-30"
}
2

削除 del

使い所：新旧のレスポンスの差分を見るときにいらないところを削除する
　　　　update_atだけ異なるので削除したい場合

//update_atだけ削除
echo '{"response": {"num": 2,"object": [{"id": "a1", "name": "名前1", "price": 1000, "updated_at": "2024-06-26"},{"id": "b2", "name": "名前2", "price": 2000, "updated_at": "2024-06-30"}]}}' | jq 'del(.response.object[].updated_at)'

{
  "response": {
    "num": 2,
    "object": [
      {
        "id": "a1",
        "name": "名前1",
        "price": 1000
      },
      {
        "id": "b2",
        "name": "名前2",
        "price": 2000
      }
    ]
  }
}