/******************************************************************************* * Copyright 2012-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. * Licensed under the Apache License, Version 2.0 (the "License"). You may not use * this file except in compliance with the License. A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. * This file is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR * CONDITIONS OF ANY KIND, either express or implied. See the License for the * specific language governing permissions and limitations under the License. * ***************************************************************************** * * AWS Tools for Windows (TM) PowerShell (TM) * */ using System; using System.Collections.Generic; using System.Linq; using System.Management.Automation; using System.Text; using Amazon.PowerShell.Common; using Amazon.Runtime; using Amazon.DynamoDBv2; using Amazon.DynamoDBv2.Model; namespace Amazon.PowerShell.Cmdlets.DDB { /// /// The GetItem operation returns a set of attributes for the item with the /// given primary key. If there is no matching item, GetItem does not return /// any data and there will be no Item element in the response. /// /// /// GetItem provides an eventually consistent read by default. If your application /// requires a strongly consistent read, set ConsistentRead to true. /// Although a strongly consistent read might take more time than an eventually consistent /// read, it always returns the last updated value. /// /// [Cmdlet("Get", "DDBItem")] [OutputType("System.String")] [AWSCmdlet("Calls the Amazon DynamoDB GetItem API operation.", Operation = new[] {"GetItem"}, SelectReturnType = typeof(Amazon.DynamoDBv2.Model.GetItemResponse))] [AWSCmdletOutput("System.String or Amazon.DynamoDBv2.Model.GetItemResponse", "This cmdlet returns a collection of System.String objects.", "The service call response (type Amazon.DynamoDBv2.Model.GetItemResponse) can also be referenced from properties attached to the cmdlet entry in the $AWSHistory stack." )] public partial class GetDDBItemCmdlet : AmazonDynamoDBClientCmdlet, IExecutor { #region Parameter AttributesToGet /// /// /// This is a legacy parameter. Use ProjectionExpression instead. For more /// information, see AttributesToGet /// in the Amazon DynamoDB Developer Guide. /// /// [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true)] public System.String[] AttributesToGet { get; set; } #endregion #region Parameter ConsistentRead /// /// /// Determines the read consistency model: If set to true, then the operation /// uses strongly consistent reads; otherwise, the operation uses eventually consistent /// reads. /// /// [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true)] public System.Boolean? ConsistentRead { get; set; } #endregion #region Parameter ExpressionAttributeName /// /// /// One or more substitution tokens for attribute names in an expression. The following /// are some use cases for using ExpressionAttributeNames:Use the # character in an expression to dereference an attribute name. For /// example, consider the following attribute name: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:You could then use this substitution in an expression, as in this example: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 Specifying /// Item Attributes in the Amazon DynamoDB Developer Guide. /// /// [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true)] [Alias("ExpressionAttributeNames")] public System.Collections.Hashtable ExpressionAttributeName { get; set; } #endregion #region Parameter Key /// /// /// A map of attribute names to AttributeValue objects, representing the /// primary key of the item to retrieve.For the primary key, you must provide all of the 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. /// /// #if !MODULAR [System.Management.Automation.Parameter(Position = 0, ValueFromPipelineByPropertyName = true, ValueFromPipeline = true)] #else [System.Management.Automation.Parameter(Position = 0, ValueFromPipelineByPropertyName = true, ValueFromPipeline = true, Mandatory = true)] [System.Management.Automation.AllowEmptyCollection] [System.Management.Automation.AllowNull] #endif [Amazon.PowerShell.Common.AWSRequiredParameter] public System.Collections.Hashtable Key { get; set; } #endregion #region Parameter 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 are returned. If any of the /// requested attributes are not found, they do not appear in the result.For more information, see Specifying /// Item Attributes in the Amazon DynamoDB Developer Guide. /// /// [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true)] public System.String ProjectionExpression { get; set; } #endregion #region Parameter ReturnConsumedCapacity /// /// /// The service has not provided documentation for this parameter; please refer to the service's API reference documentation for the latest available information. /// /// [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true)] [AWSConstantClassSource("Amazon.DynamoDBv2.ReturnConsumedCapacity")] public Amazon.DynamoDBv2.ReturnConsumedCapacity ReturnConsumedCapacity { get; set; } #endregion #region Parameter TableName /// /// /// The name of the table containing the requested item. /// /// #if !MODULAR [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true)] #else [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true, Mandatory = true)] [System.Management.Automation.AllowEmptyString] [System.Management.Automation.AllowNull] #endif [Amazon.PowerShell.Common.AWSRequiredParameter] public System.String TableName { get; set; } #endregion #region Parameter Select /// /// Use the -Select parameter to control the cmdlet output. The default value is 'Item'. /// Specifying -Select '*' will result in the cmdlet returning the whole service response (Amazon.DynamoDBv2.Model.GetItemResponse). /// Specifying the name of a property of type Amazon.DynamoDBv2.Model.GetItemResponse will result in that property being returned. /// Specifying -Select '^ParameterName' will result in the cmdlet returning the selected cmdlet parameter value. /// [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true)] public string Select { get; set; } = "Item"; #endregion #region Parameter PassThru /// /// Changes the cmdlet behavior to return the value passed to the Key parameter. /// The -PassThru parameter is deprecated, use -Select '^Key' instead. This parameter will be removed in a future version. /// [System.Obsolete("The -PassThru parameter is deprecated, use -Select '^Key' instead. This parameter will be removed in a future version.")] [System.Management.Automation.Parameter(ValueFromPipelineByPropertyName = true)] public SwitchParameter PassThru { get; set; } #endregion protected override void ProcessRecord() { this._AWSSignerType = "v4"; base.ProcessRecord(); var context = new CmdletContext(); // allow for manipulation of parameters prior to loading into context PreExecutionContextLoad(context); #pragma warning disable CS0618, CS0612 //A class member was marked with the Obsolete attribute if (ParameterWasBound(nameof(this.Select))) { context.Select = CreateSelectDelegate(Select) ?? throw new System.ArgumentException("Invalid value for -Select parameter.", nameof(this.Select)); if (this.PassThru.IsPresent) { throw new System.ArgumentException("-PassThru cannot be used when -Select is specified.", nameof(this.Select)); } } else if (this.PassThru.IsPresent) { context.Select = (response, cmdlet) => this.Key; } #pragma warning restore CS0618, CS0612 //A class member was marked with the Obsolete attribute if (this.AttributesToGet != null) { context.AttributesToGet = new List(this.AttributesToGet); } context.ConsistentRead = this.ConsistentRead; if (this.ExpressionAttributeName != null) { context.ExpressionAttributeName = new Dictionary(StringComparer.Ordinal); foreach (var hashKey in this.ExpressionAttributeName.Keys) { context.ExpressionAttributeName.Add((String)hashKey, (String)(this.ExpressionAttributeName[hashKey])); } } if (this.Key != null) { context.Key = new Dictionary(StringComparer.Ordinal); foreach (var hashKey in this.Key.Keys) { context.Key.Add((String)hashKey, (AttributeValue)(this.Key[hashKey])); } } #if MODULAR if (this.Key == null && ParameterWasBound(nameof(this.Key))) { WriteWarning("You are passing $null as a value for parameter Key which is marked as required. In case you believe this parameter was incorrectly marked as required, report this by opening an issue at https://github.com/aws/aws-tools-for-powershell/issues."); } #endif context.ProjectionExpression = this.ProjectionExpression; context.ReturnConsumedCapacity = this.ReturnConsumedCapacity; context.TableName = this.TableName; #if MODULAR if (this.TableName == null && ParameterWasBound(nameof(this.TableName))) { WriteWarning("You are passing $null as a value for parameter TableName which is marked as required. In case you believe this parameter was incorrectly marked as required, report this by opening an issue at https://github.com/aws/aws-tools-for-powershell/issues."); } #endif // allow further manipulation of loaded context prior to processing PostExecutionContextLoad(context); var output = Execute(context) as CmdletOutput; ProcessOutput(output); } #region IExecutor Members public object Execute(ExecutorContext context) { var cmdletContext = context as CmdletContext; // create request var request = new Amazon.DynamoDBv2.Model.GetItemRequest(); if (cmdletContext.AttributesToGet != null) { request.AttributesToGet = cmdletContext.AttributesToGet; } if (cmdletContext.ConsistentRead != null) { request.ConsistentRead = cmdletContext.ConsistentRead.Value; } if (cmdletContext.ExpressionAttributeName != null) { request.ExpressionAttributeNames = cmdletContext.ExpressionAttributeName; } if (cmdletContext.Key != null) { request.Key = cmdletContext.Key; } if (cmdletContext.ProjectionExpression != null) { request.ProjectionExpression = cmdletContext.ProjectionExpression; } if (cmdletContext.ReturnConsumedCapacity != null) { request.ReturnConsumedCapacity = cmdletContext.ReturnConsumedCapacity; } if (cmdletContext.TableName != null) { request.TableName = cmdletContext.TableName; } CmdletOutput output; // issue call var client = Client ?? CreateClient(_CurrentCredentials, _RegionEndpoint); try { var response = CallAWSServiceOperation(client, request); object pipelineOutput = null; pipelineOutput = cmdletContext.Select(response, this); output = new CmdletOutput { PipelineOutput = pipelineOutput, ServiceResponse = response }; } catch (Exception e) { output = new CmdletOutput { ErrorResponse = e }; } return output; } public ExecutorContext CreateContext() { return new CmdletContext(); } #endregion #region AWS Service Operation Call private Amazon.DynamoDBv2.Model.GetItemResponse CallAWSServiceOperation(IAmazonDynamoDB client, Amazon.DynamoDBv2.Model.GetItemRequest request) { Utils.Common.WriteVerboseEndpointMessage(this, client.Config, "Amazon DynamoDB", "GetItem"); try { #if DESKTOP return client.GetItem(request); #elif CORECLR return client.GetItemAsync(request).GetAwaiter().GetResult(); #else #error "Unknown build edition" #endif } catch (AmazonServiceException exc) { var webException = exc.InnerException as System.Net.WebException; if (webException != null) { throw new Exception(Utils.Common.FormatNameResolutionFailureMessage(client.Config, webException.Message), webException); } throw; } } #endregion internal partial class CmdletContext : ExecutorContext { public List AttributesToGet { get; set; } public System.Boolean? ConsistentRead { get; set; } public Dictionary ExpressionAttributeName { get; set; } public Dictionary Key { get; set; } public System.String ProjectionExpression { get; set; } public Amazon.DynamoDBv2.ReturnConsumedCapacity ReturnConsumedCapacity { get; set; } public System.String TableName { get; set; } public System.Func Select { get; set; } = (response, cmdlet) => response.Item; } } }