Create a custom promotion rule

{
  "data": {
    "attributes": {
      "reference": "ANY-EXTERNAL-REFEFERNCE",
      "reference_origin": "ANY-EXTERNAL-REFEFERNCE-ORIGIN",
      "metadata": {
        "foo": "bar"
      },
      "filters": {
        "status_eq": "pending",
        "line_items_sku_code_eq": "AAA"
      }
    },
    "relationships": {
      "promotion": {
        "data": {
          "id": "XAyRWNUzyN",
          "attributes": {
            "name": "Personal promotion",
            "type": "percentage_discount_promotions",
            "currency_code": "EUR",
            "exclusive": true,
            "priority": 2,
            "starts_at": "2018-01-01T12:00:00.000Z",
            "expires_at": "2018-01-02T12:00:00.000Z",
            "total_usage_limit": 5,
            "total_usage_count": 2,
            "active": true,
            "status": "pending",
            "weight": 112,
            "coupons_count": 2,
            "disabled_at": "2018-01-01T12:00:00.000Z",
            "created_at": "2018-01-01T12:00:00.000Z",
            "updated_at": "2018-01-01T12:00:00.000Z",
            "reference": "ANY-EXTERNAL-REFEFERNCE",
            "reference_origin": "ANY-EXTERNAL-REFEFERNCE-ORIGIN",
            "metadata": {
              "foo": "bar"
            },
            "percentage": 10
          },
          "relationships": {
            "market": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "promotion_rules": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "order_amount_promotion_rule": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "sku_list_promotion_rule": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "coupon_codes_promotion_rule": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "custom_promotion_rule": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "sku_list": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "coupons": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "attachments": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "events": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "tags": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "event_stores": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            },
            "skus": {
              "data": {
                "id": "XAyRWNUzyN"
              }
            }
          }
        }
      }
    }
  }
}