Database.RethinkDB

Documentation

data Handle

newHandle :: IO Handle

Create a new handle to the RethinkDB server.

run :: (Any a, FromResponse (Result a)) => Handle -> Exp a -> IO (Res a)

Start a new query and wait for its (first) result. If the result is an single value (Datum), then three will be no further results. If it is a sequence, then you must consume results until the sequence ends.

nextChunk :: FromResponse (Sequence a) => Handle -> Sequence a -> IO (Either Error (Sequence a))

Get the next chunk of a sequence. It is an error to request the next chunk if the sequence is already Done,

collect :: FromResponse (Sequence a) => Handle -> Sequence a -> IO (Either Error (Vector a))

Collect all the values in a sequence and make them available as a 'Vector a'.

data Error

Constructors

ProtocolError !Text

An error on the protocol level. Perhaps the socket was closed unexpectedly, or the server sent a message which the driver could not parse.

ClientError

CompileError

RuntimeError

Instances

Eq Error

Show Error

data Exp a

Instances

IsString (Exp Text)

Convenience to for automatically converting a Text to a constant expression.

ToJSON a => ToJSON (Exp a)

type Array = Vector Datum

Arrays are vectors of Datum.

type Object = HashMap Text Datum

Objects are maps from Text to Datum. Like Aeson, we're using HashMap.

data Datum

A sumtype covering all the primitive types which can appear in queries or responses.

Constructors

Null

Bool !Bool

Number !Double

String !Text

Array !Array

Object !Object

Instances

Eq Datum

Show Datum

Generic Datum

ToJSON Array

ToJSON Datum

FromJSON Array

FromJSON Datum

IsObject Object

IsDatum Object

IsDatum Array

IsDatum Datum

Any Object

Any Array

Any Datum

data Sequence a

Sequences are a bounded list of items. The server may split the sequence into multiple chunks when sending it to the client. When the response is a partial sequence, the client may request additional chunks until it gets a Done.

Instances

Show (Sequence a)

ToJSON (Sequence a)

Any a => IsSequence (Sequence a)

Any a => Any (Sequence a)

constant :: IsDatum a => a -> Exp a

Convert a Datum to an Exp.

data Table

Tables are something you can select objects from.

This type is not exported, and merely serves as a sort of phantom type. On the client tables are converted to a Sequence.

Instances

ToJSON Table

IsSequence Table

Any Table

data Database

A Database is something which contains tables. It is a server-only type.

Instances

ToJSON Database

Any Database

data SingleSelection

SingleSelection is essentially a 'Maybe Object', where Nothing is represented with Null in the network protocol.

Instances

Show SingleSelection

ToJSON SingleSelection

IsObject SingleSelection

IsDatum SingleSelection

Any SingleSelection

type Res a = Either Error (Result a)

The result of a query. It is either an error or a result (which depends on the type of the query expression). This type is named to be symmetrical to Exp, so we get this nice type for run.

 run :: Handle -> Exp a -> IO (Res a)

emptyOptions :: Object

class ToJSON a => Any a

Any value which can appear in RQL terms.

For convenience we require that it can be converted to JSON, but that is not required for all types. Only types which satisfy IsDatum are eventually converted to JSON.

Instances

Any Bool

For a boolean type, we're reusing the standard Haskell Bool type.

Any Double

Numbers are Double (unlike Aeson, which uses Scientific). No particular reason.

Any Text

For strings, we're using the Haskell Text type.

Any Database

Any SingleSelection

Any Table

Any Object

Any Array

Any Datum

Any a => Any (Sequence a)

class Any a => IsDatum a

Instances

IsDatum Bool

IsDatum Double

IsDatum Text

IsDatum SingleSelection

IsDatum Object

IsDatum Array

IsDatum Datum

class IsDatum a => IsObject a

Instances

IsObject SingleSelection

IsObject Object

class Any a => IsSequence a

Instances

IsSequence Table

Any a => IsSequence (Sequence a)

db :: Exp Text -> Exp Database

table :: Exp Text -> Exp Table

getField :: IsObject o => Exp o -> Exp Text -> Exp Datum

extractField :: (IsSequence s, IsDatum a) => Exp s -> Exp Text -> Exp (Sequence a)

get :: Exp Table -> Exp Text -> Exp SingleSelection

coerceTo :: Any v => Exp v -> Exp Text => Exp Text

getAll :: IsDatum a => Exp Table -> [Exp a] -> Maybe Text -> Exp Array

getAllIndexed :: IsDatum a => Exp Table -> [Exp a] -> Text -> Exp (Sequence Datum)

add :: [Exp Double] -> Exp Double

insert :: Exp Table -> Object -> Exp Object

limit :: Any a => Exp a -> Exp Double -> Exp Table

append :: Exp Array -> Exp Datum -> Exp Array