lambda - lambda 上的 DynamoDB 验证异常

Question

调用我的 lambda 技能时出现以下错误

ClientError: An error occurred (ValidationException) 
when calling the CreateTable operation: 1 validation error detected: 
Value '[com.amazonaws.dynamodb.v20120810.KeySchemaElement@2273ace6, 
com.amazonaws.dynamodb.v20120810.KeySchemaElement@4d13ab9, 
com.amazonaws.dynamodb.v20120810.KeySchemaElement@115e22b2]' at 
'keySchema' failed to satisfy constraint: Member must have length less than or equal to 2

这是代码:

def write_values_to_db(ddid, token, intent):
    pid = ...
    dynamodb_client = boto3.client('dynamodb')
    try:
        response = dynamodb_client.create_table(
            AttributeDefinitions=[
                {
                    'AttributeName': 'pid',
                    'AttributeType': 'S',
                },
                {
                    'AttributeName': 'ddid',
                    'AttributeType': 'S',
                },
                {
                    'AttributeName': 'token',
                    'AttributeType': 'S',
                },
            ],
            KeySchema=[
                {
                    'AttributeName': 'pid',
                    'KeyType': 'HASH',
                },
                {
                    'AttributeName': 'ddid',
                    'KeyType': 'RANGE',
                },
                {
                    'AttributeName': 'token',
                    'KeyType': 'RANGE',
                },
            ],
            ProvisionedThroughput={
                'ReadCapacityUnits': 5,
                'WriteCapacityUnits': 5,
            },
            TableName='Values',
        )
    except dynamodb_client.exceptions.ResourceInUseException:
        dynamodb_client.put_item(
            TableName='Values',
            Item={
                'pid': pid,
                'ddid': ddid,
                'token': token
            }
        )

根据我的仪表板，错误在 TableName='Values' 上线。我正在学习教程并且只更改了某些内容，所以我不明白为什么这不起作用。我无法在本地环境中进行测试，因为我有区域/凭据问题。

Answer 1

您代码中的 KeySchema 应如下所示，

AttributeDefinitions=[
            {
                'AttributeName': 'pid',
                'AttributeType': 'S',
            }
        ],
KeySchema=[
                {
                    'AttributeName': 'pid',
                    'KeyType': 'HASH'
                }
]

您最多只能有一个哈希键和一个范围键。

如果你想要额外的索引，你可以用二级索引创建它们。

http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LSI.html

以下是全局二级索引的语法。

引用: http://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/DynamoDB.html

GlobalSecondaryIndexes: [
    {
      IndexName: 'STRING_VALUE', /* required */
      KeySchema: [ /* required */
        {
          AttributeName: 'STRING_VALUE', /* required */
          KeyType: HASH | RANGE /* required */
        },
        /* more items */
      ],
      Projection: { /* required */
        NonKeyAttributes: [
          'STRING_VALUE',
          /* more items */
        ],
        ProjectionType: ALL | KEYS_ONLY | INCLUDE
      },
      ProvisionedThroughput: { /* required */
        ReadCapacityUnits: 0, /* required */
        WriteCapacityUnits: 0 /* required */
      }
    },
    /* more items */
  ]