BigQueryで使用するテーブルスキーマのJSONを作成

schema := bigquery.Schema{
	{
		Name:        "id",
		Required:    true,
		Description: "ID",
		Type:        bigquery.StringFieldType,
    }, {
		Name:                   "created_at",
		Required:               true,
		Description:            "作成された時刻",
		Type:                   bigquery.TimestampFieldType,
		DefaultValueExpression: "CURRENT_TIMESTAMP",
	},
}
b, err := schema.ToJSONFields()
if err != nil {
	panic(err)
}
fmt.Println(string(b))

[
 {
  "description": "ID",
  "mode": "REQUIRED",
  "name": "id",
  "type": "STRING"
 },
 {
  "defaultValueExpression": "CURRENT_TIMESTAMP",
  "description": "作成された時刻",
  "mode": "REQUIRED",
  "name": "created_at",
  "type": "TIMESTAMP"
 }
]