Cocker
Cocker, a socket module to aggressively handle connection retries.
NOTE: It directly inherits from net.Socket.
Table of Contents
Install
$ npm install cocker [-g]
require:
const Cocker = ;
Run Tests
$ cd cocker/$ npm test
to execute a single test file simply do:
$ node test/file-name.js
Constructor
Arguments between [ ] are optional.
or
Object options
Options
NOTE: default options are listed.
It accepts a configuration hash/object:
option
address : Object connection : Object reconnection : Object
option.address (default)
host : '127.0.0.1' port : 0 family : null /* * Specify an IPC endpoint, like a unix domain socket, if a string is * provided, the TCP-specific options above are ignored. * For further details, see "Identifying paths for IPC connections" in * the /api/net section. */ path : null
option.address (additional options for net.Socket)
// should connect from localAddress : undefined localPort: undefined // custom lookup and hints lookup : dnslookup hints : 0
option.connection
encoding : null keepAlive : true timeout : 0 noDelay : true allowHalfOpen : false
option.reconnection
trials : 3 interval : 1000 /* * A value to use for calculating the pause between two * connection attempts. Default value is the golden ratio. * Final value is calculated as: * interval * Math.pow( factor, curr.attempts + 1 ) */ factor : Math + 1 / 2
Properties
NOTE: do not mess up with these properties.
a property that holds the current configuration object
Cockeroptions : Object
current number of connection attempts
Cockerattempts : Number
a flag to signal the current status of the connection
Cockerlost : Boolean
a flag used to disable reconnection (after #hunt Promise resolution)
Cockerstop : Boolean
current lapse of time (to wait) until the next connection attempt
Cockerlapse : Number
Methods
all the methods from net.Socket module are inherited.
name | description |
---|---|
bye | end the connection. |
run | connect to a socket or attempting to. |
die | end the connection. (Promise) |
hunt | connect to a socket or attempting to. (Promise) |
prey | connect using a list of hosts. (Promise) |
watch | re-connect after losing the current connection. (Promise) |
Arguments between [ ] are optional.
Cocker.bye
end the connection (without re-connecting).
: undefined
Cocker.run
connect to a socket or attempting to (k times).
// it optionally accepts a cocker option object to reconfigure the socket. : undefined
Cocker.die
end the connection (without re-connecting).
// Promise will not be resolved until 'lost' event : Promise
Cocker.hunt
connect to a socket or attempting to (k times).
/* * Try to connect to a socket. Promise will not be resolved until 'online', * rejected after 'lost' event; it optionally accepts a cocker option object * to reconfigure the socket. */ : Promise
Cocker.prey
try to connect until success, using a list of optional hosts/config.
/* * It recursively scan a list, using #hunt Promises. The #prey Promise will * not be resolved until a connection will be made, definitively rejected * when no hosts had accepted one. * Every host in the list should be an object like Cocker.options.address. */ : Promise
Cocker.watch
try to re-connect after losing the current connection.
/* * When the current established connection is lost, it tries to reconnect. * This Promise has the same resolution as for #hunt, the only difference is * that this Promise was "registered" on socket disconnection, then it will be * resolved/rejected only after capturing a 'lost' event from the current * broken connection. See examples. */ : Promise
Events
all the events from net.Socket module are inherited.
!online: connection was established.
// when: soon after socket !connect event
!offline: connection is down.
// when: on the first !close event for the current socket
!attempt: current connection attempt.
// when: after !offline, on every connection attempt, until !lost or !online
!lost: no other attempts will be made, connection is definitively lost.
// when: soon before the last !close event.
Examples
Simple Mode
Native Promises
- connection with hunt
- connection with prey (through an address list)
- looping with watch
- looping (indefinitely) with hunt and watch
See examples.
MIT License
Copyright (c) 2013-present < Guglielmo Ferri : 44gatti@gmail.com >
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.