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Class: Aws::DynamoDB::Resource

Inherits:
Object
  • Object
show all
Defined in:
gems/aws-sdk-dynamodb/lib/aws-sdk-dynamodb/resource.rb

Actions collapse

Associations collapse

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ Resource

Returns a new instance of Resource

Parameters:

  • options ({}) (defaults to: {})

Options Hash (options):



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# File 'gems/aws-sdk-dynamodb/lib/aws-sdk-dynamodb/resource.rb', line 13

def initialize(options = {})
  @client = options[:client] || Client.new(options)
end

Instance Method Details

#batch_get_item(options = {}) ⇒ Types::BatchGetItemOutput

Examples:

Request syntax with placeholder values


dynamo_db.batch_get_item({
  request_items: { # required
    "TableName" => {
      keys: [ # required
        {
          "AttributeName" => "value", # value <Hash,Array,String,Numeric,Boolean,IO,Set,nil>
        },
      ],
      attributes_to_get: ["AttributeName"],
      consistent_read: false,
      projection_expression: "ProjectionExpression",
      expression_attribute_names: {
        "ExpressionAttributeNameVariable" => "AttributeName",
      },
    },
  },
  return_consumed_capacity: "INDEXES", # accepts INDEXES, TOTAL, NONE
})

Parameters:

  • options (Hash) (defaults to: {})

    ({})

Options Hash (options):

  • :request_items (required, Hash<String,Types::KeysAndAttributes>)

    A map of one or more table names and, for each table, a map that describes one or more items to retrieve from that table. Each table name can be used only once per BatchGetItem request.

    Each element in the map of items to retrieve consists of the following:

    • ConsistentRead - If true, a strongly consistent read is used; if false (the default), an eventually consistent read is used.

    • ExpressionAttributeNames - One or more substitution tokens for attribute names in the ProjectionExpression parameter. The following are some use cases for using ExpressionAttributeNames:

      • To access an attribute whose name conflicts with a DynamoDB reserved word.

      • To create a placeholder for repeating occurrences of an attribute name in an expression.

      • To prevent special characters in an attribute name from being misinterpreted in an expression.

      Use the # character in an expression to dereference an attribute name. For example, consider the following attribute name:

      • Percentile

      ^

      The name of this attribute conflicts with a reserved word, so it cannot be used directly in an expression. (For the complete list of reserved words, see Reserved Words in the Amazon DynamoDB Developer Guide). To work around this, you could specify the following for ExpressionAttributeNames:

      • \{"#P":"Percentile"\}

      ^

      You could then use this substitution in an expression, as in this example:

      • #P = :val

      ^

      Tokens that begin with the : character are expression attribute values, which are placeholders for the actual value at runtime.

      For more information on expression attribute names, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.

    • Keys - An array of primary key attribute values that define specific items in the table. For each primary key, you must provide all of the key attributes. For example, with a simple primary key, you only need to provide the partition key value. For a composite key, you must provide both the partition key value and the sort key value.

    • ProjectionExpression - A string that identifies one or more attributes to retrieve from the table. These attributes can include scalars, sets, or elements of a JSON document. The attributes in the expression must be separated by commas.

      If no attribute names are specified, then all attributes will be returned. If any of the requested attributes are not found, they will not appear in the result.

      For more information, see Accessing Item Attributes in the Amazon DynamoDB Developer Guide.

    • AttributesToGet - This is a legacy parameter. Use ProjectionExpression instead. For more information, see AttributesToGet in the Amazon DynamoDB Developer Guide.

  • :return_consumed_capacity (String)

    Determines the level of detail about provisioned throughput consumption that is returned in the response:

    • INDEXES - The response includes the aggregate ConsumedCapacity for the operation, together with ConsumedCapacity for each table and secondary index that was accessed.

      Note that some operations, such as GetItem and BatchGetItem, do not access any indexes at all. In these cases, specifying INDEXES will only return ConsumedCapacity information for table(s).

    • TOTAL - The response includes only the aggregate ConsumedCapacity for the operation.

    • NONE - No ConsumedCapacity details are included in the response.

Returns:



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# File 'gems/aws-sdk-dynamodb/lib/aws-sdk-dynamodb/resource.rb', line 147

def batch_get_item(options = {})
  resp = @client.batch_get_item(options)
  resp.data
end

#batch_write_item(options = {}) ⇒ Types::BatchWriteItemOutput

Examples:

Request syntax with placeholder values


dynamo_db.batch_write_item({
  request_items: { # required
    "TableName" => [
      {
        put_request: {
          item: { # required
            "AttributeName" => "value", # value <Hash,Array,String,Numeric,Boolean,IO,Set,nil>
          },
        },
        delete_request: {
          key: { # required
            "AttributeName" => "value", # value <Hash,Array,String,Numeric,Boolean,IO,Set,nil>
          },
        },
      },
    ],
  },
  return_consumed_capacity: "INDEXES", # accepts INDEXES, TOTAL, NONE
  return_item_collection_metrics: "SIZE", # accepts SIZE, NONE
})

Parameters:

  • options (Hash) (defaults to: {})

    ({})

Options Hash (options):

  • :request_items (required, Hash<String,Array>)

    A map of one or more table names and, for each table, a list of operations to be performed (DeleteRequest or PutRequest). Each element in the map consists of the following:

    • DeleteRequest - Perform a DeleteItem operation on the specified item. The item to be deleted is identified by a Key subelement:

      • Key - A map of primary key attribute values that uniquely identify the item. Each entry in this map consists of an attribute name and an attribute value. For each primary key, you must provide all of the key attributes. For example, with a simple primary key, you only need to provide a value for the partition key. For a composite primary key, you must provide values for both the partition key and the sort key.

      ^

    • PutRequest - Perform a PutItem operation on the specified item. The item to be put is identified by an Item subelement:

      • Item - A map of attributes and their values. Each entry in this map consists of an attribute name and an attribute value. Attribute values must not be null; string and binary type attributes must have lengths greater than zero; and set type attributes must not be empty. Requests that contain empty values will be rejected with a ValidationException exception.

        If you specify any attributes that are part of an index key, then the data types for those attributes must match those of the schema in the table's attribute definition.

  • :return_consumed_capacity (String)

    Determines the level of detail about provisioned throughput consumption that is returned in the response:

    • INDEXES - The response includes the aggregate ConsumedCapacity for the operation, together with ConsumedCapacity for each table and secondary index that was accessed.

      Note that some operations, such as GetItem and BatchGetItem, do not access any indexes at all. In these cases, specifying INDEXES will only return ConsumedCapacity information for table(s).

    • TOTAL - The response includes only the aggregate ConsumedCapacity for the operation.

    • NONE - No ConsumedCapacity details are included in the response.

  • :return_item_collection_metrics (String)

    Determines whether item collection metrics are returned. If set to SIZE, the response includes statistics about item collections, if any, that were modified during the operation are returned in the response. If set to NONE (the default), no statistics are returned.

Returns:



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# File 'gems/aws-sdk-dynamodb/lib/aws-sdk-dynamodb/resource.rb', line 228

def batch_write_item(options = {})
  resp = @client.batch_write_item(options)
  resp.data
end

#clientClient

Returns:



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# File 'gems/aws-sdk-dynamodb/lib/aws-sdk-dynamodb/resource.rb', line 18

def client
  @client
end

#create_table(options = {}) ⇒ Table

Examples:

Request syntax with placeholder values


table = dynamo_db.create_table({
  attribute_definitions: [ # required
    {
      attribute_name: "KeySchemaAttributeName", # required
      attribute_type: "S", # required, accepts S, N, B
    },
  ],
  table_name: "TableName", # required
  key_schema: [ # required
    {
      attribute_name: "KeySchemaAttributeName", # required
      key_type: "HASH", # required, accepts HASH, RANGE
    },
  ],
  local_secondary_indexes: [
    {
      index_name: "IndexName", # required
      key_schema: [ # required
        {
          attribute_name: "KeySchemaAttributeName", # required
          key_type: "HASH", # required, accepts HASH, RANGE
        },
      ],
      projection: { # required
        projection_type: "ALL", # accepts ALL, KEYS_ONLY, INCLUDE
        non_key_attributes: ["NonKeyAttributeName"],
      },
    },
  ],
  global_secondary_indexes: [
    {
      index_name: "IndexName", # required
      key_schema: [ # required
        {
          attribute_name: "KeySchemaAttributeName", # required
          key_type: "HASH", # required, accepts HASH, RANGE
        },
      ],
      projection: { # required
        projection_type: "ALL", # accepts ALL, KEYS_ONLY, INCLUDE
        non_key_attributes: ["NonKeyAttributeName"],
      },
      provisioned_throughput: { # required
        read_capacity_units: 1, # required
        write_capacity_units: 1, # required
      },
    },
  ],
  provisioned_throughput: { # required
    read_capacity_units: 1, # required
    write_capacity_units: 1, # required
  },
  stream_specification: {
    stream_enabled: false,
    stream_view_type: "NEW_IMAGE", # accepts NEW_IMAGE, OLD_IMAGE, NEW_AND_OLD_IMAGES, KEYS_ONLY
  },
})

Parameters:

  • options (Hash) (defaults to: {})

    ({})

Options Hash (options):

  • :attribute_definitions (required, Array<Types::AttributeDefinition>)

    An array of attributes that describe the key schema for the table and indexes.

  • :table_name (required, String)

    The name of the table to create.

  • :key_schema (required, Array<Types::KeySchemaElement>)

    Specifies the attributes that make up the primary key for a table or an index. The attributes in KeySchema must also be defined in the AttributeDefinitions array. For more information, see Data Model in the Amazon DynamoDB Developer Guide.

    Each KeySchemaElement in the array is composed of:

    • AttributeName - The name of this key attribute.

    • KeyType - The role that the key attribute will assume:

      • HASH - partition key

      • RANGE - sort key

    The partition key of an item is also known as its hash attribute. The term "hash attribute" derives from DynamoDB' usage of an internal hash function to evenly distribute data items across partitions, based on their partition key values.

    The sort key of an item is also known as its range attribute. The term "range attribute" derives from the way DynamoDB stores items with the same partition key physically close together, in sorted order by the sort key value.

    For a simple primary key (partition key), you must provide exactly one element with a KeyType of HASH.

    For a composite primary key (partition key and sort key), you must provide exactly two elements, in this order: The first element must have a KeyType of HASH, and the second element must have a KeyType of RANGE.

    For more information, see Specifying the Primary Key in the Amazon DynamoDB Developer Guide.

  • :local_secondary_indexes (Array<Types::LocalSecondaryIndex>)

    One or more local secondary indexes (the maximum is five) to be created on the table. Each index is scoped to a given partition key value. There is a 10 GB size limit per partition key value; otherwise, the size of a local secondary index is unconstrained.

    Each local secondary index in the array includes the following:

    • IndexName - The name of the local secondary index. Must be unique only for this table.

    • KeySchema - Specifies the key schema for the local secondary index. The key schema must begin with the same partition key as the table.

    • Projection - Specifies attributes that are copied (projected) from the table into the index. These are in addition to the primary key attributes and index key attributes, which are automatically projected. Each attribute specification is composed of:

      • ProjectionType - One of the following:

        • KEYS_ONLY - Only the index and primary keys are projected into the index.

        • INCLUDE - Only the specified table attributes are projected into the index. The list of projected attributes are in NonKeyAttributes.

        • ALL - All of the table attributes are projected into the index.

      • NonKeyAttributes - A list of one or more non-key attribute names that are projected into the secondary index. The total count of attributes provided in NonKeyAttributes, summed across all of the secondary indexes, must not exceed 20. If you project the same attribute into two different indexes, this counts as two distinct attributes when determining the total.

  • :global_secondary_indexes (Array<Types::GlobalSecondaryIndex>)

    One or more global secondary indexes (the maximum is five) to be created on the table. Each global secondary index in the array includes the following:

    • IndexName - The name of the global secondary index. Must be unique only for this table.

    • KeySchema - Specifies the key schema for the global secondary index.

    • Projection - Specifies attributes that are copied (projected) from the table into the index. These are in addition to the primary key attributes and index key attributes, which are automatically projected. Each attribute specification is composed of:

      • ProjectionType - One of the following:

        • KEYS_ONLY - Only the index and primary keys are projected into the index.

        • INCLUDE - Only the specified table attributes are projected into the index. The list of projected attributes are in NonKeyAttributes.

        • ALL - All of the table attributes are projected into the index.

      • NonKeyAttributes - A list of one or more non-key attribute names that are projected into the secondary index. The total count of attributes provided in NonKeyAttributes, summed across all of the secondary indexes, must not exceed 20. If you project the same attribute into two different indexes, this counts as two distinct attributes when determining the total.

    • ProvisionedThroughput - The provisioned throughput settings for the global secondary index, consisting of read and write capacity units.

  • :provisioned_throughput (required, Types::ProvisionedThroughput)

    Represents the provisioned throughput settings for a specified table or index. The settings can be modified using the UpdateTable operation.

    For current minimum and maximum provisioned throughput values, see Limits in the Amazon DynamoDB Developer Guide.

  • :stream_specification (Types::StreamSpecification)

    The settings for DynamoDB Streams on the table. These settings consist of:

    • StreamEnabled - Indicates whether Streams is to be enabled (true) or disabled (false).

    • StreamViewType - When an item in the table is modified, StreamViewType determines what information is written to the table's stream. Valid values for StreamViewType are:

      • KEYS_ONLY - Only the key attributes of the modified item are written to the stream.

      • NEW_IMAGE - The entire item, as it appears after it was modified, is written to the stream.

      • OLD_IMAGE - The entire item, as it appeared before it was modified, is written to the stream.

      • NEW_AND_OLD_IMAGES - Both the new and the old item images of the item are written to the stream.

Returns:



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# File 'gems/aws-sdk-dynamodb/lib/aws-sdk-dynamodb/resource.rb', line 455

def create_table(options = {})
  resp = @client.create_table(options)
  Table.new(
    name: resp.data.table_description.table_name,
    data: resp.data.table_description,
    client: @client
  )
end

#table(name) ⇒ Table

Parameters:

  • name (String)

Returns:



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# File 'gems/aws-sdk-dynamodb/lib/aws-sdk-dynamodb/resource.rb', line 468

def table(name)
  Table.new(
    name: name,
    client: @client
  )
end

#tables(options = {}) ⇒ Table::Collection

Examples:

Request syntax with placeholder values


dynamo_db.tables()

Parameters:

  • options (Hash) (defaults to: {})

    ({})

Returns:



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# File 'gems/aws-sdk-dynamodb/lib/aws-sdk-dynamodb/resource.rb', line 480

def tables(options = {})
  batches = Enumerator.new do |y|
    resp = @client.list_tables(options)
    resp.each_page do |page|
      batch = []
      page.data.table_names.each do |t|
        batch << Table.new(
          name: t,
          client: @client
        )
      end
      y.yield(batch)
    end
  end
  Table::Collection.new(batches)
end