Database.MongoDB.Structured.Query

This module exports several classes and combinators that operated on Structured types. Specifically, we provide the structured versions of mongoDB''s combinators, including structured query creation.

Insert

insert :: (MonadIO' m, Structured a) => a -> Action m Value

Inserts document to its corresponding collection and return the "_id" value.

insert_ :: (MonadIO' m, Structured a) => a -> Action m ()

Same as insert but discarding result.

insertMany :: (MonadIO' m, Structured a) => [a] -> Action m [Value]

Inserts documents to their corresponding collection and return their "_id" values.

insertMany_ :: (MonadIO' m, Structured a) => [a] -> Action m ()

Same as insertMany but discarding result.

insertAll :: (MonadIO' m, Structured a) => [a] -> Action m [Value]

Inserts documents to their corresponding collection and return their "_id" values. Unlike insertMany, this function keeps inserting remaining documents even if an error occurs.

insertAll_ :: (MonadIO' m, Structured a) => [a] -> Action m ()

Same as insertAll but discarding result.

Update

save :: (MonadIO' m, Structured a) => a -> Action m ()

Save document to collection. If the SObjId field is set then the document is updated, otherwise we perform an insert.

Delete

delete :: MonadIO m => StructuredSelection -> Action m ()

Delete all documents that match the selection/query.

deleteOne :: MonadIO m => StructuredSelection -> Action m ()

Delete the first documents that match the selection/query.

Order

asc :: Selectable a f t => f -> OrderExp

Sort by field, ascending

desc :: Selectable a f t => f -> OrderExp

Sort by field, descending

Query

data StructuredQuery

Wrapper for mongoDB's Query type.

Instances

Eq StructuredQuery

Show StructuredQuery

StructuredSelect StructuredQuery

limit :: StructuredQuery -> Word32

Maximum number of objects to return (default: 0, no limit).

skip :: StructuredQuery -> Word32

Number of matching objects to skip (default: 0).

sort :: StructuredQuery -> [OrderExp]

Sortresult by this order.

find :: (Functor m, MonadIO m, MonadBaseControl IO m) => StructuredQuery -> Action m StructuredCursor

Find documents satisfying query

findOne :: (MonadIO m, Structured a) => StructuredQuery -> Action m (Maybe a)

Find documents satisfying query

fetch :: (MonadIO m, Functor m, Structured a) => StructuredQuery -> Action m a

Same as findOne but throws DocNotFound if none match. Error is thrown if the document cannot e transformed.

count :: MonadIO' m => StructuredQuery -> Action m Int

Count number of documents satisfying query.

Structured selections/queries

data StructuredSelection

Wrapper for mongoDB's Selection type.

Instances

Eq StructuredSelection

Show StructuredSelection

StructuredSelect StructuredSelection

class StructuredSelect aQorS where

Analog to mongoDB's Select class

Methods

select :: Structured a => QueryExp a -> aQorS

Create a selection or query from an expression

Instances

StructuredSelect StructuredQuery

StructuredSelect StructuredSelection

class Val t => Selectable a f t | f -> a, f -> t where

Class defining a selectable type. Type a corresponds to the record type, f corresponds to the field or facet, and t corresponds to the field/facet type.

Methods

s :: f -> t -> Label

Given facet, return the BSON field name

Instances

(Selectable r f t, Selectable t f' t') => Selectable r (Nested f f') t'

(.!) :: (Selectable r f t, Selectable t f' t') => f -> f' -> Nested f f'

Combining two field names to create a Nested type.

data QueryExp a

A query expression.

Instances

Eq (QueryExp a)

Show (QueryExp a)

(.*) :: Structured a => QueryExp a

Combinator for ==

(.==) :: (Val t, Selectable a f t) => f -> t -> QueryExp a

Combinator for ==

(./=) :: (Val t, Selectable a f t) => f -> t -> QueryExp a

Combinator for $ne

(.<) :: (Val t, Selectable a f t) => f -> t -> QueryExp a

Combinator for <

(.<=) :: (Val t, Selectable a f t) => f -> t -> QueryExp a

Combinator for <=

(.>) :: (Val t, Selectable a f t) => f -> t -> QueryExp a

Combinator for >

(.>=) :: (Val t, Selectable a f t) => f -> t -> QueryExp a

Combinator for >=

(.&&) :: QueryExp a -> QueryExp a -> QueryExp a

Combinator for $and

(.||) :: QueryExp a -> QueryExp a -> QueryExp a

Combinator for $or

not_ :: QueryExp a -> QueryExp a

Combinator for $not

Cursor

data StructuredCursor

Wrapper for mongoDB's Cursor.

closeCursor :: (MonadIO m, MonadBaseControl IO m) => StructuredCursor -> Action m ()

Close the cursor.

isCursorClosed :: (MonadIO m, MonadBase IO m) => StructuredCursor -> Action m Bool

Check if the cursor is closed.

nextBatch :: (Structured a, Functor m, MonadIO m, MonadBaseControl IO m) => StructuredCursor -> Action m [Maybe a]

Return next batch of structured documents.

next :: (Structured a, MonadIO m, MonadBaseControl IO m) => StructuredCursor -> Action m (Either () (Maybe a))

Return next structured document. If failed return Left, otherwise Right of the deserialized result.

nextN :: (Structured a, Functor m, MonadIO m, MonadBaseControl IO m) => Int -> StructuredCursor -> Action m [Maybe a]

Return up to next N documents.

rest :: (Structured a, Functor m, MonadIO m, MonadBaseControl IO m) => StructuredCursor -> Action m [Maybe a]

Return the remaining documents in query result.

Rexports

module Database.MongoDB.Query

data Value

A BSON value is one of the following types of values

Instances

Eq Value

Show Value

Typeable Value

Val [Value]

Val (Maybe Value)