import { DynamoDBClientResolvedConfig, ServiceInputTypes, ServiceOutputTypes } from "../DynamoDBClient"; import { ScanInput, ScanOutput } from "../models/models_0"; import { deserializeAws_json1_0ScanCommand, serializeAws_json1_0ScanCommand } from "../protocols/Aws_json1_0"; import { getSerdePlugin } from "@aws-sdk/middleware-serde"; import { HttpRequest as __HttpRequest, HttpResponse as __HttpResponse } from "@aws-sdk/protocol-http"; import { Command as $Command } from "@aws-sdk/smithy-client"; import { FinalizeHandlerArguments, Handler, HandlerExecutionContext, MiddlewareStack, HttpHandlerOptions as __HttpHandlerOptions, MetadataBearer as __MetadataBearer, SerdeContext as __SerdeContext, } from "@aws-sdk/types"; export interface ScanCommandInput extends ScanInput {} export interface ScanCommandOutput extends ScanOutput, __MetadataBearer {} /** *

The Scan operation returns one or more items and item attributes by accessing every * item in a table or a secondary index. To have DynamoDB return fewer items, you can provide a FilterExpression operation.

*

If the total number of scanned items exceeds the maximum dataset size limit of 1 MB, the * scan stops and results are returned to the user as a LastEvaluatedKey value * to continue the scan in a subsequent operation. The results also include the number of * items exceeding the limit. A scan can result in no table data meeting the filter * criteria.

*

A single Scan operation reads up to the maximum number of items set (if * using the Limit parameter) or a maximum of 1 MB of data and then apply any * filtering to the results using FilterExpression. If * LastEvaluatedKey is present in the response, you need to paginate the * result set. For more information, see Paginating the * Results in the Amazon DynamoDB Developer Guide.

*

* Scan operations proceed sequentially; however, for faster performance on * a large table or secondary index, applications can request a parallel Scan * operation by providing the Segment and TotalSegments * parameters. For more information, see Parallel * Scan in the Amazon DynamoDB Developer Guide.

*

* Scan uses eventually consistent reads when accessing the data in a * table; therefore, the result set might not include the changes to data in the table * immediately before the operation began. If you need a consistent copy of the data, as of * the time that the Scan begins, you can set the ConsistentRead * parameter to true.

* @example * Use a bare-bones client and the command you need to make an API call. * ```javascript * import { DynamoDBClient, ScanCommand } from "@aws-sdk/client-dynamodb"; // ES Modules import * // const { DynamoDBClient, ScanCommand } = require("@aws-sdk/client-dynamodb"); // CommonJS import * const client = new DynamoDBClient(config); * const command = new ScanCommand(input); * const response = await client.send(command); * ``` * * @see {@link ScanCommandInput} for command's `input` shape. * @see {@link ScanCommandOutput} for command's `response` shape. * @see {@link DynamoDBClientResolvedConfig | config} for command's `input` shape. * */ export class ScanCommand extends $Command { // Start section: command_properties // End section: command_properties constructor(readonly input: ScanCommandInput) { // Start section: command_constructor super(); // End section: command_constructor } /** * @internal */ resolveMiddleware( clientStack: MiddlewareStack, configuration: DynamoDBClientResolvedConfig, options?: __HttpHandlerOptions ): Handler { this.middlewareStack.use(getSerdePlugin(configuration, this.serialize, this.deserialize)); const stack = clientStack.concat(this.middlewareStack); const { logger } = configuration; const clientName = "DynamoDBClient"; const commandName = "ScanCommand"; const handlerExecutionContext: HandlerExecutionContext = { logger, clientName, commandName, inputFilterSensitiveLog: ScanInput.filterSensitiveLog, outputFilterSensitiveLog: ScanOutput.filterSensitiveLog, }; const { requestHandler } = configuration; return stack.resolve( (request: FinalizeHandlerArguments) => requestHandler.handle(request.request as __HttpRequest, options || {}), handlerExecutionContext ); } private serialize(input: ScanCommandInput, context: __SerdeContext): Promise<__HttpRequest> { return serializeAws_json1_0ScanCommand(input, context); } private deserialize(output: __HttpResponse, context: __SerdeContext): Promise { return deserializeAws_json1_0ScanCommand(output, context); } // Start section: command_body_extra // End section: command_body_extra }