Safe Haskell	None
Language	Haskell2010

Database.CQRS.TabularData

Description

This module provides a backend-agnostic abstraction on top on tabular data allowing projections to be decoupled from their storage.

A Table is a list (if using Flat) or a hash map (if using WithUniqueKeys) of Tuples.

Synopsis

data TabularDataAction (cols :: Columns) where
- Insert :: Tuple Identity cols -> TabularDataAction cols
- Update :: Tuple Update cols -> Tuple Conditions cols -> TabularDataAction cols
- Upsert :: Tuple Identity (WithUniqueKey keyCols cols) -> TabularDataAction (WithUniqueKey keyCols cols)
- Delete :: Tuple Conditions cols -> TabularDataAction cols
data Condition a where
- Equal :: Eq a => a -> Condition a
- NotEqual :: Eq a => a -> Condition a
- LowerThan :: Ord a => a -> Condition a
- LowerThanOrEqual :: Ord a => a -> Condition a
- GreaterThan :: Ord a => a -> Condition a
- GreaterThanOrEqual :: Ord a => a -> Condition a
newtype Conditions a = Conditions {
- getConditions :: [Condition a]
}
equal :: Eq a => a -> Conditions a
notEqual :: Eq a => a -> Conditions a
lowerThan :: Ord a => a -> Conditions a
lowerThanOrEqual :: Ord a => a -> Conditions a
greaterThan :: Ord a => a -> Conditions a
greaterThanOrEqual :: Ord a => a -> Conditions a
data Update a where
- NoUpdate :: Update a
- Set :: a -> Update a
- Plus :: Num a => a -> Update a
- Minus :: Num a => a -> Update a
set :: a -> Update a
plus :: Num a => a -> Update a
minus :: Num a => a -> Update a
data Columns where
- Flat :: [(Symbol, Type)] -> Columns
- WithUniqueKey :: [(Symbol, Type)] -> [(Symbol, Type)] -> Columns
type Tuple f cols = FlatTuple f (Flatten cols)
type family Flatten (cols :: k) :: [(Symbol, Type)] where ...
data FlatTuple :: (Type -> Type) -> [(Symbol, Type)] -> Type where
- Nil :: FlatTuple f '[]
- Cons :: f a -> FlatTuple f cols -> FlatTuple f ('(sym, a) ': cols)
pattern (:~) :: a -> FlatTuple Identity cols -> FlatTuple Identity ('(sym, a) ': cols)
empty :: FlatTuple f '[]
type family Table (cols :: Columns) :: Type where ...
field :: forall cols sym f a. (Field f sym a (Flatten cols), Wrapper f a) => a -> Tuple f cols
ffield :: forall cols sym f a. Field f sym a (Flatten cols) => f a -> Tuple f cols
class MergeSplitTuple keyCols cols where
- mergeTuple :: (FlatTuple f keyCols, FlatTuple f cols) -> Tuple f (WithUniqueKey keyCols cols)
- splitTuple :: Tuple f (WithUniqueKey keyCols cols) -> (FlatTuple f keyCols, FlatTuple f cols)
applyTabularDataAction :: ApplyTabularDataAction f cols => Table cols -> TabularDataAction cols -> f (Table cols)
class GetKeyAndConditions keyCols cols
type family AllColumns (cs :: Type -> Constraint) (cols :: [(Symbol, Type)]) :: Constraint where ...
toList :: forall cs cols f b. AllColumns cs cols => (forall a. cs a => String -> f a -> b) -> FlatTuple f cols -> [b]

Documentation

data TabularDataAction (cols :: Columns) where Source #

Action on tabular data with an index.

Its purpose is to be used by an EffectfulProjection to create persisting backend-agnostic projections.

Constructors

Insert :: Tuple Identity cols -> TabularDataAction cols
Update :: Tuple Update cols -> Tuple Conditions cols -> TabularDataAction cols
Upsert
Fields :: Tuple Identity (WithUniqueKey keyCols cols) -> TabularDataAction (WithUniqueKey keyCols cols) Insert a new row or update the row with the same key if it exists.
Delete :: Tuple Conditions cols -> TabularDataAction cols

Instances

AllColumns Show (Flatten cols) => Show (TabularDataAction cols) Source #
Instance details Defined in Database.CQRS.TabularData Methods showsPrec :: Int -> TabularDataAction cols -> ShowS # show :: TabularDataAction cols -> String # showList :: [TabularDataAction cols] -> ShowS #

data Condition a where Source #

Constructors

Equal :: Eq a => a -> Condition a
NotEqual :: Eq a => a -> Condition a
LowerThan :: Ord a => a -> Condition a
LowerThanOrEqual :: Ord a => a -> Condition a
GreaterThan :: Ord a => a -> Condition a
GreaterThanOrEqual :: Ord a => a -> Condition a

Instances

Eq (Condition a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods (==) :: Condition a -> Condition a -> Bool # (/=) :: Condition a -> Condition a -> Bool #
Show a => Show (Condition a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods showsPrec :: Int -> Condition a -> ShowS # show :: Condition a -> String # showList :: [Condition a] -> ShowS #

newtype Conditions a Source #

Constructors

Conditions
Fields getConditions :: [Condition a]

Instances

Eq a => Wrapper Conditions a Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods wrap :: a -> Conditions a Source #
Eq (Conditions a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods (==) :: Conditions a -> Conditions a -> Bool # (/=) :: Conditions a -> Conditions a -> Bool #
Show a => Show (Conditions a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods showsPrec :: Int -> Conditions a -> ShowS # show :: Conditions a -> String # showList :: [Conditions a] -> ShowS #
Semigroup (Conditions a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods (<>) :: Conditions a -> Conditions a -> Conditions a # sconcat :: NonEmpty (Conditions a) -> Conditions a # stimes :: Integral b => b -> Conditions a -> Conditions a #
Monoid (Conditions a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods mempty :: Conditions a # mappend :: Conditions a -> Conditions a -> Conditions a # mconcat :: [Conditions a] -> Conditions a #

equal :: Eq a => a -> Conditions a Source #

notEqual :: Eq a => a -> Conditions a Source #

lowerThan :: Ord a => a -> Conditions a Source #

lowerThanOrEqual :: Ord a => a -> Conditions a Source #

greaterThan :: Ord a => a -> Conditions a Source #

greaterThanOrEqual :: Ord a => a -> Conditions a Source #

data Update a where Source #

Constructors

NoUpdate :: Update a
Set :: a -> Update a
Plus :: Num a => a -> Update a
Minus :: Num a => a -> Update a

Instances

Wrapper Update a Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods wrap :: a -> Update a Source #
Show a => Show (Update a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods showsPrec :: Int -> Update a -> ShowS # show :: Update a -> String # showList :: [Update a] -> ShowS #
Semigroup (Update a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods (<>) :: Update a -> Update a -> Update a # sconcat :: NonEmpty (Update a) -> Update a # stimes :: Integral b => b -> Update a -> Update a #
Monoid (Update a) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods mempty :: Update a # mappend :: Update a -> Update a -> Update a # mconcat :: [Update a] -> Update a #

set :: a -> Update a Source #

plus :: Num a => a -> Update a Source #

minus :: Num a => a -> Update a Source #

data Columns where Source #

Kind of types that describe columns of a table.

This is not intended as a type. It's promoted to a kind.

Use Flat for simple tables and WithUniqueKey if you want to be able to do upserts and/or store tuples in memory with a hash map instead of a list.

Constructors

Flat :: [(Symbol, Type)] -> Columns
WithUniqueKey :: [(Symbol, Type)] -> [(Symbol, Type)] -> Columns

type Tuple f cols = FlatTuple f (Flatten cols) Source #

A named tuple representing a row in the table.

type family Flatten (cols :: k) :: [(Symbol, Type)] where ... Source #

Equations

Flatten (WithUniqueKey (col ': keyCols) cols) = col ': Flatten (WithUniqueKey keyCols cols)
Flatten (WithUniqueKey '[] cols) = cols
Flatten (Flat cols) = cols

data FlatTuple :: (Type -> Type) -> [(Symbol, Type)] -> Type where Source #

Constructors

Nil :: FlatTuple f '[]
Cons :: f a -> FlatTuple f cols -> FlatTuple f ('(sym, a) ': cols)

Instances

(Eq (f a), Eq (FlatTuple f cols)) => Eq (FlatTuple f ((,) sym a ': cols)) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods (==) :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> Bool # (/=) :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> Bool #
Eq (FlatTuple f ([] :: [(Symbol, Type)])) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods (==) :: FlatTuple f [] -> FlatTuple f [] -> Bool # (/=) :: FlatTuple f [] -> FlatTuple f [] -> Bool #
(Ord (f a), Ord (FlatTuple f cols)) => Ord (FlatTuple f ((,) sym a ': cols)) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods compare :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> Ordering # (<) :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> Bool # (<=) :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> Bool # (>) :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> Bool # (>=) :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> Bool # max :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) # min :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) #
Ord (FlatTuple f ([] :: [(Symbol, Type)])) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods compare :: FlatTuple f [] -> FlatTuple f [] -> Ordering # (<) :: FlatTuple f [] -> FlatTuple f [] -> Bool # (<=) :: FlatTuple f [] -> FlatTuple f [] -> Bool # (>) :: FlatTuple f [] -> FlatTuple f [] -> Bool # (>=) :: FlatTuple f [] -> FlatTuple f [] -> Bool # max :: FlatTuple f [] -> FlatTuple f [] -> FlatTuple f [] # min :: FlatTuple f [] -> FlatTuple f [] -> FlatTuple f [] #
(AllColumns Show cols, forall a. Show a => Show (f a)) => Show (FlatTuple f cols) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods showsPrec :: Int -> FlatTuple f cols -> ShowS # show :: FlatTuple f cols -> String # showList :: [FlatTuple f cols] -> ShowS #
(Semigroup (f a), Semigroup (FlatTuple f cols)) => Semigroup (FlatTuple f ((,) sym a ': cols)) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods (<>) :: FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) # sconcat :: NonEmpty (FlatTuple f ((sym, a) ': cols)) -> FlatTuple f ((sym, a) ': cols) # stimes :: Integral b => b -> FlatTuple f ((sym, a) ': cols) -> FlatTuple f ((sym, a) ': cols) #
Semigroup (FlatTuple f ([] :: [(Symbol, Type)])) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods (<>) :: FlatTuple f [] -> FlatTuple f [] -> FlatTuple f [] # sconcat :: NonEmpty (FlatTuple f []) -> FlatTuple f [] # stimes :: Integral b => b -> FlatTuple f [] -> FlatTuple f [] #
(Monoid (f a), Monoid (FlatTuple f xs)) => Monoid (FlatTuple f ((,) sym a ': xs)) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods mempty :: FlatTuple f ((sym, a) ': xs) # mappend :: FlatTuple f ((sym, a) ': xs) -> FlatTuple f ((sym, a) ': xs) -> FlatTuple f ((sym, a) ': xs) # mconcat :: [FlatTuple f ((sym, a) ': xs)] -> FlatTuple f ((sym, a) ': xs) #
Monoid (FlatTuple f ([] :: [(Symbol, Type)])) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods mempty :: FlatTuple f [] # mappend :: FlatTuple f [] -> FlatTuple f [] -> FlatTuple f [] # mconcat :: [FlatTuple f []] -> FlatTuple f [] #
(Hashable (f a), Hashable (FlatTuple f cols)) => Hashable (FlatTuple f ((,) sym a ': cols)) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods hashWithSalt :: Int -> FlatTuple f ((sym, a) ': cols) -> Int # hash :: FlatTuple f ((sym, a) ': cols) -> Int #
Hashable (FlatTuple f ([] :: [(Symbol, Type)])) Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods hashWithSalt :: Int -> FlatTuple f [] -> Int # hash :: FlatTuple f [] -> Int #

pattern (:~) :: a -> FlatTuple Identity cols -> FlatTuple Identity ('(sym, a) ': cols) infixr 5 Source #

empty :: FlatTuple f '[] Source #

type family Table (cols :: Columns) :: Type where ... Source #

In-memory table that supports TabularDataAction. See applyTabularDataAction.

Equations

Table (WithUniqueKey keyCols cols) = HashMap (FlatTuple Identity keyCols) (FlatTuple Identity cols)
Table (Flat cols) = [FlatTuple Identity cols]

field :: forall cols sym f a. (Field f sym a (Flatten cols), Wrapper f a) => a -> Tuple f cols Source #

Create a tuple with the given field set to the given value wrapped into f. In practice, f is Conditions or Update.

It is meant to be used together with TypeApplications, e.g. field"field_name" value @

ffield :: forall cols sym f a. Field f sym a (Flatten cols) => f a -> Tuple f cols Source #

Create a tuple with the given field set to the given "wrapped" value.

It is more flexible than field but less convenient to use if the goal is to simply wrap the value inside the Applicative. In particular, it can be used with Conditions such as ffield"email" (equal "someoneexample.com")

class MergeSplitTuple keyCols cols where Source #

Methods

mergeTuple :: (FlatTuple f keyCols, FlatTuple f cols) -> Tuple f (WithUniqueKey keyCols cols) Source #

splitTuple :: Tuple f (WithUniqueKey keyCols cols) -> (FlatTuple f keyCols, FlatTuple f cols) Source #

Instances

MergeSplitTuple ([] :: [(Symbol, Type)]) cols Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods mergeTuple :: (FlatTuple f [], FlatTuple f cols) -> Tuple f (WithUniqueKey [] cols) Source # splitTuple :: Tuple f (WithUniqueKey [] cols) -> (FlatTuple f [], FlatTuple f cols) Source #
MergeSplitTuple keyCols cols => MergeSplitTuple (a ': keyCols) cols Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods mergeTuple :: (FlatTuple f (a ': keyCols), FlatTuple f cols) -> Tuple f (WithUniqueKey (a ': keyCols) cols) Source # splitTuple :: Tuple f (WithUniqueKey (a ': keyCols) cols) -> (FlatTuple f (a ': keyCols), FlatTuple f cols) Source #

applyTabularDataAction :: ApplyTabularDataAction f cols => Table cols -> TabularDataAction cols -> f (Table cols) Source #

Apply some TabularDataAction on an in-memory table and return a new table.

class GetKeyAndConditions keyCols cols Source #

Used to optimise operations on the in-memory storage. When we want to update or delete rows based on some conditions that would match one row matching its key, it's more efficient to use alter instead of traversing the hash map.

Minimal complete definition

getKeyAndConditions

Instances

GetKeyAndConditions ([] :: [(Symbol, Type)]) cols Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods getKeyAndConditions :: Tuple Conditions (WithUniqueKey [] cols) -> Maybe (FlatTuple Identity [], FlatTuple Conditions cols) Source #
GetKeyAndConditions keyCols cols => GetKeyAndConditions ((,) sym a ': keyCols) cols Source #
Instance details Defined in Database.CQRS.TabularData.Internal Methods getKeyAndConditions :: Tuple Conditions (WithUniqueKey ((sym, a) ': keyCols) cols) -> Maybe (FlatTuple Identity ((sym, a) ': keyCols), FlatTuple Conditions cols) Source #

type family AllColumns (cs :: Type -> Constraint) (cols :: [(Symbol, Type)]) :: Constraint where ... Source #

Equations

AllColumns _ '[] = ()
AllColumns cs ('(sym, a) ': cols) = (cs a, KnownSymbol sym, AllColumns cs cols)

toList :: forall cs cols f b. AllColumns cs cols => (forall a. cs a => String -> f a -> b) -> FlatTuple f cols -> [b] Source #

Transform a tuple into a list of pairs given a function to transform the field values.

cs is some constraint that the values need to satisfy. For example, toListShow (name value -> (name, maybe NULL show (getLast value))) :: Tuple Last cols -> [(String, String)] @