[Python3 / pynamodb] create_table時に Table read and write throughput must be at least 1, and cannot be null

発生したエラー

E pynamodb.exceptions.TableError: Failed to create table: An error occurred (ValidationException) on request (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx) on table (some_data) when calling the CreateTable operation: Table read and write throughput must be at least 1, and cannot be null

.venv/lib/python3.8/site-packages/pynamodb/connection/base.py:651: TableError

Table read and write throughput must be at least 1, and cannot be nullがエラーの原因っぽいことはすぐにわかった。
けれど、Table read and write throughputをどうやって設定するのかが一見してわからない。

この対処法を本記事に記載する。

環境

ソースコード

ダメなやつ

from pynamodb.models import Model


class SomeModel(Model):
    class Meta:
        table_name = "some_data"
        region = "us-east-1"

    some_id: UnicodeAttribute = UnicodeAttribute(hash_key=True)
    user_id: UnicodeAttribute = UnicodeAttribute()


def create_some_table():
    model = SomeModel
    model_meta_class = getattr(SomeModel, "Meta")
    setattr(model_meta_class, "host", "http://localhost:8000")
    setattr(model_meta_class, "region", "ap-northeast-1")
    setattr(model_meta_class, "table_name", "some_data")
    setattr(model_meta_class, "aws_access_key_id", "dummy")
    setattr(model_meta_class, "aws_secret_access_key", "dummy")

    model.create_table(wait=True)


create_some_table()

このソースコードのままcreate_some_tableを実行すると、以下のようなエラーが出る

E pynamodb.exceptions.TableError: Failed to create table: An error occurred (ValidationException) on request (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx) on table (some_data) when calling the CreateTable operation: Table read and write throughput must be at least 1, and cannot be null

.venv/lib/python3.8/site-packages/pynamodb/connection/base.py:651: TableError

対処法

以下のように、setattr(model_meta_class, "billing_mode", "PAY_PER_REQUEST")を追加したら直った。

対処後

from pynamodb.models import Model


class SomeModel(Model):
    class Meta:
        table_name = "some_data"
        region = "us-east-1"

    some_id: UnicodeAttribute = UnicodeAttribute(hash_key=True)
    user_id: UnicodeAttribute = UnicodeAttribute()


def create_some_table():
    model = SomeModel
    model_meta_class = getattr(SomeModel, "Meta")
    setattr(model_meta_class, "host", "http://localhost:8000")
    setattr(model_meta_class, "billing_mode", "PAY_PER_REQUEST")  # <- 追加
    setattr(model_meta_class, "region", "ap-northeast-1")
    setattr(model_meta_class, "table_name", "some_data")
    setattr(model_meta_class, "aws_access_key_id", "dummy")
    setattr(model_meta_class, "aws_secret_access_key", "dummy")

    model.create_table(wait=True)


create_some_table()

これでOK。

Table read and write throughputというのは、billing_modeで指定できるものだったようだ。

なら、そう書いて欲しいぽよ...

参考資料