Middleware

All middleware should have the following interface.

classDiagram

class Middleware {
  -name: str
  +constructor(config: Config)
  +connect()
  +close()
  +isOpen() boolean
}

Where config is a key:value pair dictionary that is scoped to the middleware by its name property. So if the name property is 'bus', the config object will be scoped to config.bus.

Cache

The cache class is a type of component with the following interface,

classDiagram

class Middleware
class Cache {
  +setKey(id, value)
  +getKey(id) any|null
}

Cache <|-- Middleware

config

The configuration parameters for the default cache middleware should be the connection url.

Parameters:

name	type	description
conn_url	str	a string with the connection url to the middleware. Defaults to the configuration variable conf.cache.url

setKey(id, value)

Parameters:

name	type	description
id	str	the key in the middleware to set
value	any	the value to store in the middleware at location id

getKey(id)

gets the value of a key from the cache middleware

Parameters:

name	type	description
id	str	the key to retrieve its value from the middleware.

Returns:

Either the value in the middleware, or null if it does not exist in the middleware.

Bus

classDiagram

class Middleware
class Bus {
  +String prefix
  +Dict routePrefix

  +connect()
  +subscribe(route, inputHandler, onConsuming, onMessage)
  +send(route, message) boolean
  +emitEvent(event) boolean
}

Bus <|-- Middleware

config

Parameters:

name	type	description
conn_url	str	The url to connect to the bus. defaults to conf.bus.url
prefix	str	The prefix to use when setting up the route. Defaults to conf.bus.prefix

subscribe(route, inputHandler, onConsuming, onMessage)

Parameters:

name	type	description
route	str	the route to subscribe to
inputHandler	INPUTHANDLER	a function to handle messages routed to the service
onConsuming	ONCONSUMING	a call back function when the service is consuming

send(route, message)

Parameters:

name	type	description
route	str	the route to subscribe to
message	Payload	a function to handle messages routed to the service

Returns:

Boolean true if successful.

emitEvent(event)

Parameters:

name	type	description
event	Event	the event to emit

Returns:

Boolean true if successful.