Hasql.ListenNotify

LISTEN/NOTIFY with hasql.

Listen

newtype Identifier

A Postgres identifier.

Constructors

Identifier ByteString

Instances

Show Identifier

Defined in Hasql.ListenNotify

Methods

showsPrec :: Int -> Identifier -> ShowS

show :: Identifier -> String

showList :: [Identifier] -> ShowS

Eq Identifier

Defined in Hasql.ListenNotify

Methods

(==) :: Identifier -> Identifier -> Bool

(/=) :: Identifier -> Identifier -> Bool

Ord Identifier

Defined in Hasql.ListenNotify

Methods

compare :: Identifier -> Identifier -> Ordering

(<) :: Identifier -> Identifier -> Bool

(<=) :: Identifier -> Identifier -> Bool

(>) :: Identifier -> Identifier -> Bool

(>=) :: Identifier -> Identifier -> Bool

max :: Identifier -> Identifier -> Identifier

min :: Identifier -> Identifier -> Identifier

listen :: Identifier -> Statement () ()

Listen to a channel.

https://www.postgresql.org/docs/current/sql-listen.html

unlisten :: Identifier -> Statement () ()

Stop listening to a channel.

https://www.postgresql.org/docs/current/sql-unlisten.html

unlistenAll :: Statement () ()

Stop listening to all channels.

https://www.postgresql.org/docs/current/sql-unlisten.html

escapeIdentifier :: Text -> Session Identifier

Escape a string as a Postgres identifier.

https://www.postgresql.org/docs/15/libpq-exec.html

data Notification

An incoming notification.

Constructors

Notification

Fields

• channel :: !Text
• payload :: !Text
• pid :: !CPid

Instances

Generic Notification

Defined in Hasql.ListenNotify

Associated Types

type Rep Notification :: Type -> Type

Methods

from :: Notification -> Rep Notification x

to :: Rep Notification x -> Notification

Show Notification

Defined in Hasql.ListenNotify

Methods

showsPrec :: Int -> Notification -> ShowS

show :: Notification -> String

showList :: [Notification] -> ShowS

Eq Notification

Defined in Hasql.ListenNotify

Methods

(==) :: Notification -> Notification -> Bool

(/=) :: Notification -> Notification -> Bool

type Rep Notification

Defined in Hasql.ListenNotify

type Rep Notification = D1 ('MetaData "Notification" "Hasql.ListenNotify" "hasql-listen-notify-0.1.0.1-9QQM5cfHmzE5QxjgAd2Msk" 'False) (C1 ('MetaCons "Notification" 'PrefixI 'True) (S1 ('MetaSel ('Just "channel") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Text) :*: (S1 ('MetaSel ('Just "payload") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Text) :*: S1 ('MetaSel ('Just "pid") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 CPid))))

await :: Session Notification

Get the next notification received from the server.

https://www.postgresql.org/docs/current/libpq-notify.html

poll :: Session (Maybe Notification)

Variant of await that doesn't block.

backendPid :: Session CPid

Get the PID of the backend process handling this session. This can be used to filter out notifications that originate from this session.

https://www.postgresql.org/docs/current/libpq-status.html

Notify

data Notify

An outgoing notification.

Constructors

Notify

Fields

• channel :: !Text
• payload :: !Text

Instances

Generic Notify

Defined in Hasql.ListenNotify

Associated Types

type Rep Notify :: Type -> Type

Methods

from :: Notify -> Rep Notify x

to :: Rep Notify x -> Notify

Show Notify

Defined in Hasql.ListenNotify

Methods

showsPrec :: Int -> Notify -> ShowS

show :: Notify -> String

showList :: [Notify] -> ShowS

Eq Notify

Defined in Hasql.ListenNotify

Methods

(==) :: Notify -> Notify -> Bool

(/=) :: Notify -> Notify -> Bool

type Rep Notify

Defined in Hasql.ListenNotify

type Rep Notify = D1 ('MetaData "Notify" "Hasql.ListenNotify" "hasql-listen-notify-0.1.0.1-9QQM5cfHmzE5QxjgAd2Msk" 'False) (C1 ('MetaCons "Notify" 'PrefixI 'True) (S1 ('MetaSel ('Just "channel") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Text) :*: S1 ('MetaSel ('Just "payload") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Text)))

notify :: Statement Notify ()

Notify a channel.

https://www.postgresql.org/docs/current/sql-notify.html