IndexError: list index out of range with moto

Question

我正在模拟一个返回dynamodb查询的内部函数。查询的begins_with抛出错误IndexError: list index out of range。

我改变了查询并删除了begins_with，但仍然得到相同的错误。如果我删除AND condition from KeyConditionExpression，那么查询工作。

下面是查询:

val = 'test#val#testing'    
input_query = {
'TableName': <table_name>,
'KeyConditionExpression': '#23b62 = :23b62 And #23b63 = :23b63)',
'FilterExpression': 'contains(#23b64, :23b64)',
'ProjectionExpression': '#23b60,#23b61',
'ExpressionAttributeNames': {'#23b60': 'level', '#23b61': 'test_id', '#23b62': 'PK', '#23b63': 'SK', '#23b64': 'used_in'},
'ExpressionAttributeValues': {':23b62': {'S': 'testing'}, ':23b63': {'S': val}, ':23b64': {'S': 'test'}}
}

新建查询:

dynamodb_client.query(TableName="table",
KeyConditionExpression = "#PK = :PK And #SK = :SK",
ExpressionAttributeNames = {
"#PK": "PK",
"#SK": "SK"
},
FilterExpression = "contains(Used, :used)",
ExpressionAttributeValues ={
":PK": {"S": "tests"},
":SK": {"S": "test#en#testing"},
":used": {"S": "testing"}
}
)

测试用例:

from botocore.exceptions import ClientError
from dynamodb_json import json_util as dynamodb_json
import logging
from contextlib import contextmanager
import pytest
from unittest.mock import patch

@contextmanager
def ddb_setup(dynamodb_resource):
table = dynamodb_resource.create_table(
TableName='table',
KeySchema=[
{
'AttributeName': 'PK',
'KeyType': 'HASH'
}, {
'AttributeName': 'SK',
'KeyType': 'SORT'
},
],
AttributeDefinitions=[
{
'AttributeName': 'PK',
'AttributeType': 'S'
}, {
'AttributeName': 'SK',
'AttributeType': 'S'
},
],
ProvisionedThroughput={
'ReadCapacityUnits': 1,
'WriteCapacityUnits': 1,
}
)
yield

class TestDynamoDB:
def test_create_table(self, dynamodb_resource, dynamodb_client):
with ddb_setup(dynamodb_resource):
try:
response = dynamodb_client.describe_table(
TableName='table')
resp = dynamodb_client.query(TableName="table",
KeyConditionExpression = "#PK = :PK And #SK = :SK",
ExpressionAttributeNames = {
"#PK": "PK",
"#SK": "SK"
},
FilterExpression = "contains(Used, :used)",
ExpressionAttributeValues ={
":PK": {"S": "tests"},
":SK": {"S": "test#en#testing"},
":used": {"S": "testing"}
}
)
except ClientError as err:
logger.error(f"error: {err.response['Error']['Code']}", )
assert err.response['Error']['Code'] == 'ResourceNotFoundException'

有谁能建议我如何用AND条件运行这个查询吗?

Answer 1

下面是一个使用pytest和moto的工作测试配置示例。我已经添加了代码，展示了如何使用资源和客户端API来使用AND条件。

import boto3
import boto3.dynamodb.conditions as conditions
import moto
import pytest
TABLE_NAME = "data"
@pytest.fixture
def test_table():
with moto.mock_dynamodb():
client = boto3.client("dynamodb")
client.create_table(
AttributeDefinitions=[
{"AttributeName": "PK", "AttributeType": "S"},
{"AttributeName": "SK", "AttributeType": "S"}
],
TableName=TABLE_NAME,
KeySchema=[
{"AttributeName": "PK", "KeyType": "HASH"},
{"AttributeName": "SK", "KeyType": "RANGE"}
],
BillingMode="PAY_PER_REQUEST"
)
table = boto3.resource("dynamodb").Table(TABLE_NAME)
table.put_item(Item={
"PK": "pk_value",
"SK": "sk_value"
})
yield TABLE_NAME

def test_query_with_and_using_resource(test_table):
table = boto3.resource("dynamodb").Table(TABLE_NAME)
response = table.query(
KeyConditionExpression=conditions.Key("PK").eq("pk_value") & conditions.Key("SK").eq("sk_value")
)
assert len(response["Items"]) == 1
def test_query_with_and_using_client(test_table):
client = boto3.client("dynamodb")
response = client.query(
TableName=TABLE_NAME,
KeyConditionExpression="#PK = :PK AND #SK = :SK",
ExpressionAttributeNames={
"#PK": "PK",
"#SK": "SK"
},
ExpressionAttributeValues={
":PK": {"S": "pk_value"},
":SK": {"S": "sk_value"}
}
)
assert len(response["Items"]) == 1

首先，我们设置一个带有虚拟项的表，然后有两个测试，第一个用于资源，第二个用于客户端API。也许这能帮你找出错误。

Answer 2

AWS使用关键字RANGE表示某项是排序键。(不知道为什么…)

如果您替换:'KeyType': 'SORT'与'KeyType': 'RANGE'测试通过。

---

我假设AWS在创建具有未知KeyType的表时抛出更明显的错误。如果你愿意，你可以在Moto的Github上创建一个功能请求，让Moto复制这种行为，并抛出同样的异常。