MessageDb.StreamName

Streams are the fundamental unit of organization of evented, service-oriented systems. They are both the storage and the transport of messages in message-based systems. And they are the principle storage medium of applicative entity data.

Streams are created by writing a message to the stream. Messages are appended to the end of streams. If the stream doesn't exist when an event is appended to it, the event will be appended at position 0. If the stream already exists, the event will be appended at the next position number.

Read more at: http://docs.eventide-project.org/core-concepts/streams

Documentation

newtype StreamName

Name of a stream. Look into categoryOfStream or identifierOfStream to parse out the category or identifier from the stream name.

Constructors

StreamName

Fields

• streamNameToText :: Text

  Convert the StreamName to Text.

Instances

Eq StreamName

Defined in MessageDb.StreamName

Methods

(==) :: StreamName -> StreamName -> Bool

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

Ord StreamName

Defined in MessageDb.StreamName

Methods

compare :: StreamName -> StreamName -> Ordering

(<) :: StreamName -> StreamName -> Bool

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

(>) :: StreamName -> StreamName -> Bool

(>=) :: StreamName -> StreamName -> Bool

max :: StreamName -> StreamName -> StreamName

min :: StreamName -> StreamName -> StreamName

Show StreamName

Defined in MessageDb.StreamName

Methods

showsPrec :: Int -> StreamName -> ShowS

show :: StreamName -> String

showList :: [StreamName] -> ShowS

IsString StreamName

Defined in MessageDb.StreamName

Methods

fromString :: String -> StreamName

Semigroup StreamName

Defined in MessageDb.StreamName

Methods

(<>) :: StreamName -> StreamName -> StreamName

sconcat :: NonEmpty StreamName -> StreamName

stimes :: Integral b => b -> StreamName -> StreamName

ToJSON StreamName

Defined in MessageDb.StreamName

Methods

toJSON :: StreamName -> Value

toEncoding :: StreamName -> Encoding

toJSONList :: [StreamName] -> Value

toEncodingList :: [StreamName] -> Encoding

FromJSON StreamName

Defined in MessageDb.StreamName

Methods

parseJSON :: Value -> Parser StreamName

parseJSONList :: Value -> Parser [StreamName]

Category

data Category

A Category represents everything in the StreamName up to the first hyphen (-). For example, the category for the stream name, "account-1234", is "account".

Instances

Eq Category

Defined in MessageDb.StreamName

Methods

(==) :: Category -> Category -> Bool

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

Ord Category

Defined in MessageDb.StreamName

Methods

compare :: Category -> Category -> Ordering

(<) :: Category -> Category -> Bool

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

(>) :: Category -> Category -> Bool

(>=) :: Category -> Category -> Bool

max :: Category -> Category -> Category

min :: Category -> Category -> Category

Show Category

Defined in MessageDb.StreamName

Methods

showsPrec :: Int -> Category -> ShowS

show :: Category -> String

showList :: [Category] -> ShowS

ToJSON Category

Defined in MessageDb.StreamName

Methods

toJSON :: Category -> Value

toEncoding :: Category -> Encoding

toJSONList :: [Category] -> Value

toEncodingList :: [Category] -> Encoding

FromJSON Category

Defined in MessageDb.StreamName

Methods

parseJSON :: Value -> Parser Category

parseJSONList :: Value -> Parser [Category]

categoryOfStream :: StreamName -> Category

Gets the category of a stream. For example for "account-123" it would return "account".

categoryToText :: Category -> Text

Convert from a Category to a Text.

category :: Text -> Category

Identifier

newtype Identifier

The identifier part of a stream name. Anything after the first hyphen (-).

Constructors

Identifier

Fields

• identifierNameToText :: Text

  Convert from an Identifier to a 'Text.

Instances

Eq Identifier

Defined in MessageDb.StreamName

Methods

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

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

Ord Identifier

Defined in MessageDb.StreamName

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

Show Identifier

Defined in MessageDb.StreamName

Methods

showsPrec :: Int -> Identifier -> ShowS

show :: Identifier -> String

showList :: [Identifier] -> ShowS

ToJSON Identifier

Defined in MessageDb.StreamName

Methods

toJSON :: Identifier -> Value

toEncoding :: Identifier -> Encoding

toJSONList :: [Identifier] -> Value

toEncodingList :: [Identifier] -> Encoding

FromJSON Identifier

Defined in MessageDb.StreamName

Methods

parseJSON :: Value -> Parser Identifier

parseJSONList :: Value -> Parser [Identifier]

identifierOfStream :: StreamName -> Maybe Identifier

Gets the identifier of a stream from a StreamName. For example "account-ed3b4af7-b4a0-499e-8a16-a09763811274" would return Just "ed3b4af7-b4a0-499e-8a16-a09763811274", and "account" would return Nothing.

addIdentifierToCategory :: Category -> Identifier -> StreamName

Add an identifier to a Category. For example category "account" and identifier "123" would return "account-123".

addMaybeIdentifierToCategory :: Category -> Maybe Identifier -> StreamName

Add a maybe identifier, allowing you to add an identifier to the stream name if it is Just.