{-# LANGUAGE DeriveGeneric #-} {-# LANGUAGE DuplicateRecordFields #-} {-# LANGUAGE NamedFieldPuns #-} {-# LANGUAGE OverloadedStrings #-} {-# LANGUAGE RecordWildCards #-} {-# LANGUAGE StrictData #-} {-# LANGUAGE NoImplicitPrelude #-} {-# OPTIONS_GHC -fno-warn-unused-imports #-} {-# OPTIONS_GHC -fno-warn-unused-matches #-} -- Derived from AWS service descriptions, licensed under Apache 2.0. -- | -- Module : Amazonka.DynamoDB.Types.KeysAndAttributes -- Copyright : (c) 2013-2023 Brendan Hay -- License : Mozilla Public License, v. 2.0. -- Maintainer : Brendan Hay -- Stability : auto-generated -- Portability : non-portable (GHC extensions) module Amazonka.DynamoDB.Types.KeysAndAttributes where import qualified Amazonka.Core as Core import qualified Amazonka.Core.Lens.Internal as Lens import qualified Amazonka.Data as Data import Amazonka.DynamoDB.Types.AttributeValue import Amazonka.DynamoDB.Types.WriteRequest import qualified Amazonka.Prelude as Prelude -- | Represents a set of primary keys and, for each key, the attributes to -- retrieve from 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. For a composite primary key, you must provide /both/ the -- partition key and the sort key. -- -- /See:/ 'newKeysAndAttributes' smart constructor. data KeysAndAttributes = KeysAndAttributes' { -- | This is a legacy parameter. Use @ProjectionExpression@ instead. For more -- information, see -- -- in the /Amazon DynamoDB Developer Guide/. attributesToGet :: Prelude.Maybe (Prelude.NonEmpty Prelude.Text), -- | The consistency of a read operation. If set to @true@, then a strongly -- consistent read is used; otherwise, an eventually consistent read is -- used. consistentRead :: Prelude.Maybe Prelude.Bool, -- | One or more substitution tokens for attribute names in an expression. -- 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 -- -- 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 -- -- in the /Amazon DynamoDB Developer Guide/. expressionAttributeNames :: Prelude.Maybe (Prelude.HashMap Prelude.Text Prelude.Text), -- | 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 @ProjectionExpression@ 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 -- -- in the /Amazon DynamoDB Developer Guide/. projectionExpression :: Prelude.Maybe Prelude.Text, -- | The primary key attribute values that define the items and the -- attributes associated with the items. keys :: Prelude.NonEmpty (Prelude.HashMap Prelude.Text AttributeValue) } deriving (Prelude.Eq, Prelude.Read, Prelude.Show, Prelude.Generic) -- | -- Create a value of 'KeysAndAttributes' with all optional fields omitted. -- -- Use or to modify other optional fields. -- -- The following record fields are available, with the corresponding lenses provided -- for backwards compatibility: -- -- 'attributesToGet', 'keysAndAttributes_attributesToGet' - This is a legacy parameter. Use @ProjectionExpression@ instead. For more -- information, see -- -- in the /Amazon DynamoDB Developer Guide/. -- -- 'consistentRead', 'keysAndAttributes_consistentRead' - The consistency of a read operation. If set to @true@, then a strongly -- consistent read is used; otherwise, an eventually consistent read is -- used. -- -- 'expressionAttributeNames', 'keysAndAttributes_expressionAttributeNames' - One or more substitution tokens for attribute names in an expression. -- 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 -- -- 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 -- -- in the /Amazon DynamoDB Developer Guide/. -- -- 'projectionExpression', 'keysAndAttributes_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 @ProjectionExpression@ 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 -- -- in the /Amazon DynamoDB Developer Guide/. -- -- 'keys', 'keysAndAttributes_keys' - The primary key attribute values that define the items and the -- attributes associated with the items. newKeysAndAttributes :: -- | 'keys' Prelude.NonEmpty (Prelude.HashMap Prelude.Text AttributeValue) -> KeysAndAttributes newKeysAndAttributes pKeys_ = KeysAndAttributes' { attributesToGet = Prelude.Nothing, consistentRead = Prelude.Nothing, expressionAttributeNames = Prelude.Nothing, projectionExpression = Prelude.Nothing, keys = Lens.coerced Lens.# pKeys_ } -- | This is a legacy parameter. Use @ProjectionExpression@ instead. For more -- information, see -- -- in the /Amazon DynamoDB Developer Guide/. keysAndAttributes_attributesToGet :: Lens.Lens' KeysAndAttributes (Prelude.Maybe (Prelude.NonEmpty Prelude.Text)) keysAndAttributes_attributesToGet = Lens.lens (\KeysAndAttributes' {attributesToGet} -> attributesToGet) (\s@KeysAndAttributes' {} a -> s {attributesToGet = a} :: KeysAndAttributes) Prelude.. Lens.mapping Lens.coerced -- | The consistency of a read operation. If set to @true@, then a strongly -- consistent read is used; otherwise, an eventually consistent read is -- used. keysAndAttributes_consistentRead :: Lens.Lens' KeysAndAttributes (Prelude.Maybe Prelude.Bool) keysAndAttributes_consistentRead = Lens.lens (\KeysAndAttributes' {consistentRead} -> consistentRead) (\s@KeysAndAttributes' {} a -> s {consistentRead = a} :: KeysAndAttributes) -- | One or more substitution tokens for attribute names in an expression. -- 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 -- -- 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 -- -- in the /Amazon DynamoDB Developer Guide/. keysAndAttributes_expressionAttributeNames :: Lens.Lens' KeysAndAttributes (Prelude.Maybe (Prelude.HashMap Prelude.Text Prelude.Text)) keysAndAttributes_expressionAttributeNames = Lens.lens (\KeysAndAttributes' {expressionAttributeNames} -> expressionAttributeNames) (\s@KeysAndAttributes' {} a -> s {expressionAttributeNames = a} :: KeysAndAttributes) Prelude.. Lens.mapping Lens.coerced -- | 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 @ProjectionExpression@ 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 -- -- in the /Amazon DynamoDB Developer Guide/. keysAndAttributes_projectionExpression :: Lens.Lens' KeysAndAttributes (Prelude.Maybe Prelude.Text) keysAndAttributes_projectionExpression = Lens.lens (\KeysAndAttributes' {projectionExpression} -> projectionExpression) (\s@KeysAndAttributes' {} a -> s {projectionExpression = a} :: KeysAndAttributes) -- | The primary key attribute values that define the items and the -- attributes associated with the items. keysAndAttributes_keys :: Lens.Lens' KeysAndAttributes (Prelude.NonEmpty (Prelude.HashMap Prelude.Text AttributeValue)) keysAndAttributes_keys = Lens.lens (\KeysAndAttributes' {keys} -> keys) (\s@KeysAndAttributes' {} a -> s {keys = a} :: KeysAndAttributes) Prelude.. Lens.coerced instance Data.FromJSON KeysAndAttributes where parseJSON = Data.withObject "KeysAndAttributes" ( \x -> KeysAndAttributes' Prelude.<$> (x Data..:? "AttributesToGet") Prelude.<*> (x Data..:? "ConsistentRead") Prelude.<*> ( x Data..:? "ExpressionAttributeNames" Data..!= Prelude.mempty ) Prelude.<*> (x Data..:? "ProjectionExpression") Prelude.<*> (x Data..: "Keys") ) instance Prelude.Hashable KeysAndAttributes where hashWithSalt _salt KeysAndAttributes' {..} = _salt `Prelude.hashWithSalt` attributesToGet `Prelude.hashWithSalt` consistentRead `Prelude.hashWithSalt` expressionAttributeNames `Prelude.hashWithSalt` projectionExpression `Prelude.hashWithSalt` keys instance Prelude.NFData KeysAndAttributes where rnf KeysAndAttributes' {..} = Prelude.rnf attributesToGet `Prelude.seq` Prelude.rnf consistentRead `Prelude.seq` Prelude.rnf expressionAttributeNames `Prelude.seq` Prelude.rnf projectionExpression `Prelude.seq` Prelude.rnf keys instance Data.ToJSON KeysAndAttributes where toJSON KeysAndAttributes' {..} = Data.object ( Prelude.catMaybes [ ("AttributesToGet" Data..=) Prelude.<$> attributesToGet, ("ConsistentRead" Data..=) Prelude.<$> consistentRead, ("ExpressionAttributeNames" Data..=) Prelude.<$> expressionAttributeNames, ("ProjectionExpression" Data..=) Prelude.<$> projectionExpression, Prelude.Just ("Keys" Data..= keys) ] )