{-# LANGUAGE DeriveDataTypeable #-} {-# LANGUAGE DeriveGeneric #-} {-# LANGUAGE OverloadedStrings #-} {-# LANGUAGE RecordWildCards #-} {-# LANGUAGE TypeFamilies #-} {-# OPTIONS_GHC -fno-warn-unused-imports #-} {-# OPTIONS_GHC -fno-warn-unused-binds #-} {-# OPTIONS_GHC -fno-warn-unused-matches #-} -- Derived from AWS service descriptions, licensed under Apache 2.0. -- | -- Module : Network.AWS.DynamoDB.Query -- Copyright : (c) 2013-2015 Brendan Hay -- License : Mozilla Public License, v. 2.0. -- Maintainer : Brendan Hay <brendan.g.hay@gmail.com> -- Stability : auto-generated -- Portability : non-portable (GHC extensions) -- -- A /Query/ operation uses the primary key of a table or a secondary index -- to directly access items from that table or index. -- -- Use the /KeyConditionExpression/ parameter to provide a specific hash -- key value. The /Query/ operation will return all of the items from the -- table or index with that hash key value. You can optionally narrow the -- scope of the /Query/ operation by specifying a range key value and a -- comparison operator in /KeyConditionExpression/. You can use the -- /ScanIndexForward/ parameter to get results in forward or reverse order, -- by range key or by index key. -- -- Queries that do not return results consume the minimum number of read -- capacity units for that type of read operation. -- -- If the total number of items meeting the query criteria exceeds the -- result set size limit of 1 MB, the query stops and results are returned -- to the user with the /LastEvaluatedKey/ element to continue the query in -- a subsequent operation. Unlike a /Scan/ operation, a /Query/ operation -- never returns both an empty result set and a /LastEvaluatedKey/ value. -- /LastEvaluatedKey/ is only provided if the results exceed 1 MB, or if -- you have used the /Limit/ parameter. -- -- You can query a table, a local secondary index, or a global secondary -- index. For a query on a table or on a local secondary index, you can set -- the /ConsistentRead/ parameter to 'true' and obtain a strongly -- consistent result. Global secondary indexes support eventually -- consistent reads only, so do not specify /ConsistentRead/ when querying -- a global secondary index. -- -- /See:/ <http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_Query.html AWS API Reference> for Query. -- -- This operation returns paginated results. module Network.AWS.DynamoDB.Query ( -- * Creating a Request query , Query -- * Request Lenses , qKeyConditions , qProjectionExpression , qAttributesToGet , qExpressionAttributeNames , qFilterExpression , qQueryFilter , qConsistentRead , qExpressionAttributeValues , qReturnConsumedCapacity , qScanIndexForward , qLimit , qSelect , qKeyConditionExpression , qConditionalOperator , qExclusiveStartKey , qIndexName , qTableName -- * Destructuring the Response , queryResponse , QueryResponse -- * Response Lenses , qrsLastEvaluatedKey , qrsCount , qrsScannedCount , qrsItems , qrsConsumedCapacity , qrsResponseStatus ) where import Network.AWS.DynamoDB.Types import Network.AWS.DynamoDB.Types.Product import Network.AWS.Pager import Network.AWS.Prelude import Network.AWS.Request import Network.AWS.Response -- | Represents the input of a /Query/ operation. -- -- /See:/ 'query' smart constructor. data Query = Query' { _qKeyConditions :: !(Maybe (Map Text Condition)) , _qProjectionExpression :: !(Maybe Text) , _qAttributesToGet :: !(Maybe (List1 Text)) , _qExpressionAttributeNames :: !(Maybe (Map Text Text)) , _qFilterExpression :: !(Maybe Text) , _qQueryFilter :: !(Maybe (Map Text Condition)) , _qConsistentRead :: !(Maybe Bool) , _qExpressionAttributeValues :: !(Maybe (Map Text AttributeValue)) , _qReturnConsumedCapacity :: !(Maybe ReturnConsumedCapacity) , _qScanIndexForward :: !(Maybe Bool) , _qLimit :: !(Maybe Nat) , _qSelect :: !(Maybe Select) , _qKeyConditionExpression :: !(Maybe Text) , _qConditionalOperator :: !(Maybe ConditionalOperator) , _qExclusiveStartKey :: !(Maybe (Map Text AttributeValue)) , _qIndexName :: !(Maybe Text) , _qTableName :: !Text } deriving (Eq,Read,Show,Data,Typeable,Generic) -- | Creates a value of 'Query' with the minimum fields required to make a request. -- -- Use one of the following lenses to modify other fields as desired: -- -- * 'qKeyConditions' -- -- * 'qProjectionExpression' -- -- * 'qAttributesToGet' -- -- * 'qExpressionAttributeNames' -- -- * 'qFilterExpression' -- -- * 'qQueryFilter' -- -- * 'qConsistentRead' -- -- * 'qExpressionAttributeValues' -- -- * 'qReturnConsumedCapacity' -- -- * 'qScanIndexForward' -- -- * 'qLimit' -- -- * 'qSelect' -- -- * 'qKeyConditionExpression' -- -- * 'qConditionalOperator' -- -- * 'qExclusiveStartKey' -- -- * 'qIndexName' -- -- * 'qTableName' query :: Text -- ^ 'qTableName' -> Query query pTableName_ = Query' { _qKeyConditions = Nothing , _qProjectionExpression = Nothing , _qAttributesToGet = Nothing , _qExpressionAttributeNames = Nothing , _qFilterExpression = Nothing , _qQueryFilter = Nothing , _qConsistentRead = Nothing , _qExpressionAttributeValues = Nothing , _qReturnConsumedCapacity = Nothing , _qScanIndexForward = Nothing , _qLimit = Nothing , _qSelect = Nothing , _qKeyConditionExpression = Nothing , _qConditionalOperator = Nothing , _qExclusiveStartKey = Nothing , _qIndexName = Nothing , _qTableName = pTableName_ } -- | This is a legacy parameter, for backward compatibility. New applications -- should use /KeyConditionExpression/ instead. Do not combine legacy -- parameters and expression parameters in a single API call; otherwise, -- DynamoDB will return a /ValidationException/ exception. -- -- The selection criteria for the query. For a query on a table, you can -- have conditions only on the table primary key attributes. You must -- provide the hash key attribute name and value as an 'EQ' condition. You -- can optionally provide a second condition, referring to the range key -- attribute. -- -- If you don\'t provide a range key condition, all of the items that match -- the hash key will be retrieved. If a /FilterExpression/ or /QueryFilter/ -- is present, it will be applied after the items are retrieved. -- -- For a query on an index, you can have conditions only on the index key -- attributes. You must provide the index hash attribute name and value as -- an 'EQ' condition. You can optionally provide a second condition, -- referring to the index key range attribute. -- -- Each /KeyConditions/ element consists of an attribute name to compare, -- along with the following: -- -- - /AttributeValueList/ - One or more values to evaluate against the -- supplied attribute. The number of values in the list depends on the -- /ComparisonOperator/ being used. -- -- For type Number, value comparisons are numeric. -- -- String value comparisons for greater than, equals, or less than are -- based on ASCII character code values. For example, 'a' is greater -- than 'A', and 'a' is greater than 'B'. For a list of code values, -- see <http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters>. -- -- For Binary, DynamoDB treats each byte of the binary data as unsigned -- when it compares binary values. -- -- - /ComparisonOperator/ - A comparator for evaluating attributes, for -- example, equals, greater than, less than, and so on. -- -- For /KeyConditions/, only the following comparison operators are -- supported: -- -- 'EQ | LE | LT | GE | GT | BEGINS_WITH | BETWEEN' -- -- The following are descriptions of these comparison operators. -- -- - 'EQ' : Equal. -- -- /AttributeValueList/ can contain only one /AttributeValue/ of -- type String, Number, or Binary (not a set type). If an item -- contains an /AttributeValue/ element of a different type than -- the one specified in the request, the value does not match. For -- example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. Also, -- '{\"N\":\"6\"}' does not equal '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'LE' : Less than or equal. -- -- /AttributeValueList/ can contain only one /AttributeValue/ -- element of type String, Number, or Binary (not a set type). If -- an item contains an /AttributeValue/ element of a different type -- than the one provided in the request, the value does not match. -- For example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. -- Also, '{\"N\":\"6\"}' does not compare to -- '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'LT' : Less than. -- -- /AttributeValueList/ can contain only one /AttributeValue/ of -- type String, Number, or Binary (not a set type). If an item -- contains an /AttributeValue/ element of a different type than -- the one provided in the request, the value does not match. For -- example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. Also, -- '{\"N\":\"6\"}' does not compare to -- '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'GE' : Greater than or equal. -- -- /AttributeValueList/ can contain only one /AttributeValue/ -- element of type String, Number, or Binary (not a set type). If -- an item contains an /AttributeValue/ element of a different type -- than the one provided in the request, the value does not match. -- For example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. -- Also, '{\"N\":\"6\"}' does not compare to -- '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'GT' : Greater than. -- -- /AttributeValueList/ can contain only one /AttributeValue/ -- element of type String, Number, or Binary (not a set type). If -- an item contains an /AttributeValue/ element of a different type -- than the one provided in the request, the value does not match. -- For example, '{\"S\":\"6\"}' does not equal '{\"N\":\"6\"}'. -- Also, '{\"N\":\"6\"}' does not compare to -- '{\"NS\":[\"6\", \"2\", \"1\"]}'. -- -- - 'BEGINS_WITH' : Checks for a prefix. -- -- /AttributeValueList/ can contain only one /AttributeValue/ of -- type String or Binary (not a Number or a set type). The target -- attribute of the comparison must be of type String or Binary -- (not a Number or a set type). -- -- - 'BETWEEN' : Greater than or equal to the first value, and less -- than or equal to the second value. -- -- /AttributeValueList/ must contain two /AttributeValue/ elements -- of the same type, either String, Number, or Binary (not a set -- type). A target attribute matches if the target value is greater -- than, or equal to, the first element and less than, or equal to, -- the second element. If an item contains an /AttributeValue/ -- element of a different type than the one provided in the -- request, the value does not match. For example, '{\"S\":\"6\"}' -- does not compare to '{\"N\":\"6\"}'. Also, '{\"N\":\"6\"}' does -- not compare to '{\"NS\":[\"6\", \"2\", \"1\"]}' -- -- For usage examples of /AttributeValueList/ and /ComparisonOperator/, see -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LegacyConditionalParameters.html Legacy Conditional Parameters> -- in the /Amazon DynamoDB Developer Guide/. qKeyConditions :: Lens' Query (HashMap Text Condition) qKeyConditions = lens _qKeyConditions (\ s a -> s{_qKeyConditions = a}) . _Default . _Map; -- | 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 -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html Accessing Item Attributes> -- in the /Amazon DynamoDB Developer Guide/. -- -- /ProjectionExpression/ replaces the legacy /AttributesToGet/ parameter. qProjectionExpression :: Lens' Query (Maybe Text) qProjectionExpression = lens _qProjectionExpression (\ s a -> s{_qProjectionExpression = a}); -- | This is a legacy parameter, for backward compatibility. New applications -- should use /ProjectionExpression/ instead. Do not combine legacy -- parameters and expression parameters in a single API call; otherwise, -- DynamoDB will return a /ValidationException/ exception. -- -- This parameter allows you to retrieve attributes of type List or Map; -- however, it cannot retrieve individual elements within a List or a Map. -- -- The names of one or more attributes to retrieve. If no attribute names -- are provided, then all attributes will be returned. If any of the -- requested attributes are not found, they will not appear in the result. -- -- Note that /AttributesToGet/ has no effect on provisioned throughput -- consumption. DynamoDB determines capacity units consumed based on item -- size, not on the amount of data that is returned to an application. -- -- You cannot use both /AttributesToGet/ and /Select/ together in a /Query/ -- request, /unless/ the value for /Select/ is 'SPECIFIC_ATTRIBUTES'. (This -- usage is equivalent to specifying /AttributesToGet/ without any value -- for /Select/.) -- -- If you query a local secondary index and request only attributes that -- are projected into that index, the operation will read only the index -- and not the table. If any of the requested attributes are not projected -- into the local secondary index, DynamoDB will fetch each of these -- attributes from the parent table. This extra fetching incurs additional -- throughput cost and latency. -- -- If you query a global secondary index, you can only request attributes -- that are projected into the index. Global secondary index queries cannot -- fetch attributes from the parent table. qAttributesToGet :: Lens' Query (Maybe (NonEmpty Text)) qAttributesToGet = lens _qAttributesToGet (\ s a -> s{_qAttributesToGet = a}) . mapping _List1; -- | 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 -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html 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 -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.AccessingItemAttributes.html Accessing Item Attributes> -- in the /Amazon DynamoDB Developer Guide/. qExpressionAttributeNames :: Lens' Query (HashMap Text Text) qExpressionAttributeNames = lens _qExpressionAttributeNames (\ s a -> s{_qExpressionAttributeNames = a}) . _Default . _Map; -- | A string that contains conditions that DynamoDB applies after the -- /Query/ operation, but before the data is returned to you. Items that do -- not satisfy the /FilterExpression/ criteria are not returned. -- -- A /FilterExpression/ is applied after the items have already been read; -- the process of filtering does not consume any additional read capacity -- units. -- -- For more information, see -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/QueryAndScan.html#FilteringResults Filter Expressions> -- in the /Amazon DynamoDB Developer Guide/. -- -- /FilterExpression/ replaces the legacy /QueryFilter/ and -- /ConditionalOperator/ parameters. qFilterExpression :: Lens' Query (Maybe Text) qFilterExpression = lens _qFilterExpression (\ s a -> s{_qFilterExpression = a}); -- | This is a legacy parameter, for backward compatibility. New applications -- should use /FilterExpression/ instead. Do not combine legacy parameters -- and expression parameters in a single API call; otherwise, DynamoDB will -- return a /ValidationException/ exception. -- -- A condition that evaluates the query results after the items are read -- and returns only the desired values. -- -- This parameter does not support attributes of type List or Map. -- -- A /QueryFilter/ is applied after the items have already been read; the -- process of filtering does not consume any additional read capacity -- units. -- -- If you provide more than one condition in the /QueryFilter/ map, then by -- default all of the conditions must evaluate to true. In other words, the -- conditions are ANDed together. (You can use the /ConditionalOperator/ -- parameter to OR the conditions instead. If you do this, then at least -- one of the conditions must evaluate to true, rather than all of them.) -- -- Note that /QueryFilter/ does not allow key attributes. You cannot define -- a filter condition on a hash key or range key. -- -- Each /QueryFilter/ element consists of an attribute name to compare, -- along with the following: -- -- - /AttributeValueList/ - One or more values to evaluate against the -- supplied attribute. The number of values in the list depends on the -- operator specified in /ComparisonOperator/. -- -- For type Number, value comparisons are numeric. -- -- String value comparisons for greater than, equals, or less than are -- based on ASCII character code values. For example, 'a' is greater -- than 'A', and 'a' is greater than 'B'. For a list of code values, -- see <http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters>. -- -- For type Binary, DynamoDB treats each byte of the binary data as -- unsigned when it compares binary values. -- -- For information on specifying data types in JSON, see -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataFormat.html JSON Data Format> -- in the /Amazon DynamoDB Developer Guide/. -- -- - /ComparisonOperator/ - A comparator for evaluating attributes. For -- example, equals, greater than, less than, etc. -- -- The following comparison operators are available: -- -- 'EQ | NE | LE | LT | GE | GT | NOT_NULL | NULL | CONTAINS | NOT_CONTAINS | BEGINS_WITH | IN | BETWEEN' -- -- For complete descriptions of all comparison operators, see the -- <http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_Condition.html Condition> -- data type. -- qQueryFilter :: Lens' Query (HashMap Text Condition) qQueryFilter = lens _qQueryFilter (\ s a -> s{_qQueryFilter = a}) . _Default . _Map; -- | Determines the read consistency model: If set to 'true', then the -- operation uses strongly consistent reads; otherwise, the operation uses -- eventually consistent reads. -- -- Strongly consistent reads are not supported on global secondary indexes. -- If you query a global secondary index with /ConsistentRead/ set to -- 'true', you will receive a /ValidationException/. qConsistentRead :: Lens' Query (Maybe Bool) qConsistentRead = lens _qConsistentRead (\ s a -> s{_qConsistentRead = a}); -- | One or more values that can be substituted in an expression. -- -- Use the __:__ (colon) character in an expression to dereference an -- attribute value. For example, suppose that you wanted to check whether -- the value of the /ProductStatus/ attribute was one of the following: -- -- 'Available | Backordered | Discontinued' -- -- You would first need to specify /ExpressionAttributeValues/ as follows: -- -- '{ \":avail\":{\"S\":\"Available\"}, \":back\":{\"S\":\"Backordered\"}, \":disc\":{\"S\":\"Discontinued\"} }' -- -- You could then use these values in an expression, such as this: -- -- 'ProductStatus IN (:avail, :back, :disc)' -- -- For more information on expression attribute values, see -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.SpecifyingConditions.html Specifying Conditions> -- in the /Amazon DynamoDB Developer Guide/. qExpressionAttributeValues :: Lens' Query (HashMap Text AttributeValue) qExpressionAttributeValues = lens _qExpressionAttributeValues (\ s a -> s{_qExpressionAttributeValues = a}) . _Default . _Map; -- | Undocumented member. qReturnConsumedCapacity :: Lens' Query (Maybe ReturnConsumedCapacity) qReturnConsumedCapacity = lens _qReturnConsumedCapacity (\ s a -> s{_qReturnConsumedCapacity = a}); -- | Specifies the order in which to return the query results - either -- ascending ('true') or descending ('false'). -- -- Items with the same hash key are stored in sorted order by range key .If -- the range key data type is Number, the results are stored in numeric -- order. For type String, the results are returned in order of ASCII -- character code values. For type Binary, DynamoDB treats each byte of the -- binary data as unsigned. -- -- If /ScanIndexForward/ is 'true', DynamoDB returns the results in order, -- by range key. This is the default behavior. -- -- If /ScanIndexForward/ is 'false', DynamoDB sorts the results in -- descending order by range key, and then returns the results to the -- client. qScanIndexForward :: Lens' Query (Maybe Bool) qScanIndexForward = lens _qScanIndexForward (\ s a -> s{_qScanIndexForward = a}); -- | The maximum number of items to evaluate (not necessarily the number of -- matching items). If DynamoDB processes the number of items up to the -- limit while processing the results, it stops the operation and returns -- the matching values up to that point, and a key in /LastEvaluatedKey/ to -- apply in a subsequent operation, so that you can pick up where you left -- off. Also, if the processed data set size exceeds 1 MB before DynamoDB -- reaches this limit, it stops the operation and returns the matching -- values up to the limit, and a key in /LastEvaluatedKey/ to apply in a -- subsequent operation to continue the operation. For more information, -- see -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/QueryAndScan.html Query and Scan> -- in the /Amazon DynamoDB Developer Guide/. qLimit :: Lens' Query (Maybe Natural) qLimit = lens _qLimit (\ s a -> s{_qLimit = a}) . mapping _Nat; -- | The attributes to be returned in the result. You can retrieve all item -- attributes, specific item attributes, the count of matching items, or in -- the case of an index, some or all of the attributes projected into the -- index. -- -- - 'ALL_ATTRIBUTES' - Returns all of the item attributes from the -- specified table or index. If you query a local secondary index, then -- for each matching item in the index DynamoDB will fetch the entire -- item from the parent table. If the index is configured to project -- all item attributes, then all of the data can be obtained from the -- local secondary index, and no fetching is required. -- -- - 'ALL_PROJECTED_ATTRIBUTES' - Allowed only when querying an index. -- Retrieves all attributes that have been projected into the index. If -- the index is configured to project all attributes, this return value -- is equivalent to specifying 'ALL_ATTRIBUTES'. -- -- - 'COUNT' - Returns the number of matching items, rather than the -- matching items themselves. -- -- - 'SPECIFIC_ATTRIBUTES' - Returns only the attributes listed in -- /AttributesToGet/. This return value is equivalent to specifying -- /AttributesToGet/ without specifying any value for /Select/. -- -- If you query a local secondary index and request only attributes -- that are projected into that index, the operation will read only the -- index and not the table. If any of the requested attributes are not -- projected into the local secondary index, DynamoDB will fetch each -- of these attributes from the parent table. This extra fetching -- incurs additional throughput cost and latency. -- -- If you query a global secondary index, you can only request -- attributes that are projected into the index. Global secondary index -- queries cannot fetch attributes from the parent table. -- -- If neither /Select/ nor /AttributesToGet/ are specified, DynamoDB -- defaults to 'ALL_ATTRIBUTES' when accessing a table, and -- 'ALL_PROJECTED_ATTRIBUTES' when accessing an index. You cannot use both -- /Select/ and /AttributesToGet/ together in a single request, unless the -- value for /Select/ is 'SPECIFIC_ATTRIBUTES'. (This usage is equivalent -- to specifying /AttributesToGet/ without any value for /Select/.) -- -- If you use the /ProjectionExpression/ parameter, then the value for -- /Select/ can only be 'SPECIFIC_ATTRIBUTES'. Any other value for /Select/ -- will return an error. qSelect :: Lens' Query (Maybe Select) qSelect = lens _qSelect (\ s a -> s{_qSelect = a}); -- | The condition that specifies the key value(s) for items to be retrieved -- by the /Query/ action. -- -- The condition must perform an equality test on a single hash key value. -- The condition can also perform one of several comparison tests on a -- single range key value. /Query/ can use /KeyConditionExpression/ to -- retrieve one item with a given hash and range key value, or several -- items that have the same hash key value but different range key values. -- -- The hash key equality test is required, and must be specified in the -- following format: -- -- 'hashAttributeName' /=/ ':hashval' -- -- If you also want to provide a range key condition, it must be combined -- using /AND/ with the hash key condition. Following is an example, using -- the __=__ comparison operator for the range key: -- -- 'hashAttributeName' /=/ ':hashval' /AND/ 'rangeAttributeName' /=/ -- ':rangeval' -- -- Valid comparisons for the range key condition are as follows: -- -- - 'rangeAttributeName' /=/ ':rangeval' - true if the range key is -- equal to ':rangeval'. -- -- - 'rangeAttributeName' /\</ ':rangeval' - true if the range key is -- less than ':rangeval'. -- -- - 'rangeAttributeName' /\<=/ ':rangeval' - true if the range key is -- less than or equal to ':rangeval'. -- -- - 'rangeAttributeName' />/ ':rangeval' - true if the range key is -- greater than ':rangeval'. -- -- - 'rangeAttributeName' />=/ ':rangeval' - true if the range key is -- greater than or equal to ':rangeval'. -- -- - 'rangeAttributeName' /BETWEEN/ ':rangeval1' /AND/ ':rangeval2' - -- true if the range key is greater than or equal to ':rangeval1', and -- less than or equal to ':rangeval2'. -- -- - /begins_with (/'rangeAttributeName', ':rangeval'/)/ - true if the -- range key begins with a particular operand. (You cannot use this -- function with a range key that is of type Number.) Note that the -- function name 'begins_with' is case-sensitive. -- -- Use the /ExpressionAttributeValues/ parameter to replace tokens such as -- ':hashval' and ':rangeval' with actual values at runtime. -- -- You can optionally use the /ExpressionAttributeNames/ parameter to -- replace the names of the hash and range attributes with placeholder -- tokens. This option might be necessary if an attribute name conflicts -- with a DynamoDB reserved word. For example, the following -- /KeyConditionExpression/ parameter causes an error because /Size/ is a -- reserved word: -- -- - 'Size = :myval' -- -- To work around this, define a placeholder (such a '#S') to represent the -- attribute name /Size/. /KeyConditionExpression/ then is as follows: -- -- - '#S = :myval' -- -- For a list of reserved words, see -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html Reserved Words> -- in the /Amazon DynamoDB Developer Guide/. -- -- For more information on /ExpressionAttributeNames/ and -- /ExpressionAttributeValues/, see -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ExpressionPlaceholders.html Using Placeholders for Attribute Names and Values> -- in the /Amazon DynamoDB Developer Guide/. -- -- /KeyConditionExpression/ replaces the legacy /KeyConditions/ parameter. qKeyConditionExpression :: Lens' Query (Maybe Text) qKeyConditionExpression = lens _qKeyConditionExpression (\ s a -> s{_qKeyConditionExpression = a}); -- | This is a legacy parameter, for backward compatibility. New applications -- should use /FilterExpression/ instead. Do not combine legacy parameters -- and expression parameters in a single API call; otherwise, DynamoDB will -- return a /ValidationException/ exception. -- -- A logical operator to apply to the conditions in a /QueryFilter/ map: -- -- - 'AND' - If all of the conditions evaluate to true, then the entire -- map evaluates to true. -- -- - 'OR' - If at least one of the conditions evaluate to true, then the -- entire map evaluates to true. -- -- If you omit /ConditionalOperator/, then 'AND' is the default. -- -- The operation will succeed only if the entire map evaluates to true. -- -- This parameter does not support attributes of type List or Map. qConditionalOperator :: Lens' Query (Maybe ConditionalOperator) qConditionalOperator = lens _qConditionalOperator (\ s a -> s{_qConditionalOperator = a}); -- | The primary key of the first item that this operation will evaluate. Use -- the value that was returned for /LastEvaluatedKey/ in the previous -- operation. -- -- The data type for /ExclusiveStartKey/ must be String, Number or Binary. -- No set data types are allowed. qExclusiveStartKey :: Lens' Query (HashMap Text AttributeValue) qExclusiveStartKey = lens _qExclusiveStartKey (\ s a -> s{_qExclusiveStartKey = a}) . _Default . _Map; -- | The name of an index to query. This index can be any local secondary -- index or global secondary index on the table. Note that if you use the -- /IndexName/ parameter, you must also provide /TableName./ qIndexName :: Lens' Query (Maybe Text) qIndexName = lens _qIndexName (\ s a -> s{_qIndexName = a}); -- | The name of the table containing the requested items. qTableName :: Lens' Query Text qTableName = lens _qTableName (\ s a -> s{_qTableName = a}); instance AWSPager Query where page rq rs | stop (rs ^. qrsLastEvaluatedKey) = Nothing | stop (rs ^. qrsItems) = Nothing | otherwise = Just $ rq & qExclusiveStartKey .~ rs ^. qrsLastEvaluatedKey instance AWSRequest Query where type Rs Query = QueryResponse request = postJSON dynamoDB response = receiveJSON (\ s h x -> QueryResponse' <$> (x .?> "LastEvaluatedKey" .!@ mempty) <*> (x .?> "Count") <*> (x .?> "ScannedCount") <*> (x .?> "Items" .!@ mempty) <*> (x .?> "ConsumedCapacity") <*> (pure (fromEnum s))) instance ToHeaders Query where toHeaders = const (mconcat ["X-Amz-Target" =# ("DynamoDB_20120810.Query" :: ByteString), "Content-Type" =# ("application/x-amz-json-1.0" :: ByteString)]) instance ToJSON Query where toJSON Query'{..} = object (catMaybes [("KeyConditions" .=) <$> _qKeyConditions, ("ProjectionExpression" .=) <$> _qProjectionExpression, ("AttributesToGet" .=) <$> _qAttributesToGet, ("ExpressionAttributeNames" .=) <$> _qExpressionAttributeNames, ("FilterExpression" .=) <$> _qFilterExpression, ("QueryFilter" .=) <$> _qQueryFilter, ("ConsistentRead" .=) <$> _qConsistentRead, ("ExpressionAttributeValues" .=) <$> _qExpressionAttributeValues, ("ReturnConsumedCapacity" .=) <$> _qReturnConsumedCapacity, ("ScanIndexForward" .=) <$> _qScanIndexForward, ("Limit" .=) <$> _qLimit, ("Select" .=) <$> _qSelect, ("KeyConditionExpression" .=) <$> _qKeyConditionExpression, ("ConditionalOperator" .=) <$> _qConditionalOperator, ("ExclusiveStartKey" .=) <$> _qExclusiveStartKey, ("IndexName" .=) <$> _qIndexName, Just ("TableName" .= _qTableName)]) instance ToPath Query where toPath = const "/" instance ToQuery Query where toQuery = const mempty -- | Represents the output of a /Query/ operation. -- -- /See:/ 'queryResponse' smart constructor. data QueryResponse = QueryResponse' { _qrsLastEvaluatedKey :: !(Maybe (Map Text AttributeValue)) , _qrsCount :: !(Maybe Int) , _qrsScannedCount :: !(Maybe Int) , _qrsItems :: !(Maybe [Map Text AttributeValue]) , _qrsConsumedCapacity :: !(Maybe ConsumedCapacity) , _qrsResponseStatus :: !Int } deriving (Eq,Read,Show,Data,Typeable,Generic) -- | Creates a value of 'QueryResponse' with the minimum fields required to make a request. -- -- Use one of the following lenses to modify other fields as desired: -- -- * 'qrsLastEvaluatedKey' -- -- * 'qrsCount' -- -- * 'qrsScannedCount' -- -- * 'qrsItems' -- -- * 'qrsConsumedCapacity' -- -- * 'qrsResponseStatus' queryResponse :: Int -- ^ 'qrsResponseStatus' -> QueryResponse queryResponse pResponseStatus_ = QueryResponse' { _qrsLastEvaluatedKey = Nothing , _qrsCount = Nothing , _qrsScannedCount = Nothing , _qrsItems = Nothing , _qrsConsumedCapacity = Nothing , _qrsResponseStatus = pResponseStatus_ } -- | The primary key of the item where the operation stopped, inclusive of -- the previous result set. Use this value to start a new operation, -- excluding this value in the new request. -- -- If /LastEvaluatedKey/ is empty, then the \"last page\" of results has -- been processed and there is no more data to be retrieved. -- -- If /LastEvaluatedKey/ is not empty, it does not necessarily mean that -- there is more data in the result set. The only way to know when you have -- reached the end of the result set is when /LastEvaluatedKey/ is empty. qrsLastEvaluatedKey :: Lens' QueryResponse (HashMap Text AttributeValue) qrsLastEvaluatedKey = lens _qrsLastEvaluatedKey (\ s a -> s{_qrsLastEvaluatedKey = a}) . _Default . _Map; -- | The number of items in the response. -- -- If you used a /QueryFilter/ in the request, then /Count/ is the number -- of items returned after the filter was applied, and /ScannedCount/ is -- the number of matching items before> the filter was applied. -- -- If you did not use a filter in the request, then /Count/ and -- /ScannedCount/ are the same. qrsCount :: Lens' QueryResponse (Maybe Int) qrsCount = lens _qrsCount (\ s a -> s{_qrsCount = a}); -- | The number of items evaluated, before any /QueryFilter/ is applied. A -- high /ScannedCount/ value with few, or no, /Count/ results indicates an -- inefficient /Query/ operation. For more information, see -- <http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/QueryAndScan.html#Count Count and ScannedCount> -- in the /Amazon DynamoDB Developer Guide/. -- -- If you did not use a filter in the request, then /ScannedCount/ is the -- same as /Count/. qrsScannedCount :: Lens' QueryResponse (Maybe Int) qrsScannedCount = lens _qrsScannedCount (\ s a -> s{_qrsScannedCount = a}); -- | An array of item attributes that match the query criteria. Each element -- in this array consists of an attribute name and the value for that -- attribute. qrsItems :: Lens' QueryResponse [HashMap Text AttributeValue] qrsItems = lens _qrsItems (\ s a -> s{_qrsItems = a}) . _Default . _Coerce; -- | Undocumented member. qrsConsumedCapacity :: Lens' QueryResponse (Maybe ConsumedCapacity) qrsConsumedCapacity = lens _qrsConsumedCapacity (\ s a -> s{_qrsConsumedCapacity = a}); -- | The response status code. qrsResponseStatus :: Lens' QueryResponse Int qrsResponseStatus = lens _qrsResponseStatus (\ s a -> s{_qrsResponseStatus = a});