This is a node.js library for my DCP Protocol, analogous to the http library for the HTTP protocol, but DCP is optimized for IoT. See the DCP Protocol Specification for details or my IoT Manager project which is a working full stack IoT demonstration using this module. Key features implemented:
- Works on both TCP and UDP transport layers
- TCP Request/Response cycles can be synchronous or asynchronous (i.e. close the TCP socket after sending a request and wait for a response, or leave the socket open and handle responses as they come in)
- Handles socket management and message framing
- Parses DCP messages into Request and Response objects
- Provides utility methods for creating DCP Request and Response objects
- Provides utility methods for formatting DCP messages from DCP Request and Response objects
- Listen method accepts a callback function for handling incoming messages with Request and Response objects as parameters
- Send method accepts a Request object and a callback function for handling the Response with the Response object as a parameter
- Response callbacks are registered by a unique TRANSACTION-ID header carried on both both requests and responses to tie them together when asynchronous. If no TRANSACTION-ID is provided, one will be generated and applied as a header automatically.
See the DCP Protocol Specification for protocol details here: https://dcp.rev4labs.com
There are two demo scripts that are meant to be used together: thingOneDemoScript.js and thingTwoDemoScript.js. They are meant to be run in separate console windows (or machines). Start thingTwoDemoScript.js first in one console window, then run thingOneDemoScript.js in another console. You will see the two scripts communicate with each other. Thing 1 will send a request to Thing 2. Then Thing 2 will run a request handler and respond to Thing 1. Thing 1 will then run a response handler that prints the response to the console. Note the constants and comments at the top of each script. You can try both TCP and UDP transport protocols.
These scripts should provide a good example of how to use the library and get started. The library is still in development and will likely change, but a lot of the core functionality is working should you want to experiment with it.
The Device Control Protocol (DCP) is an application level protocol optimized for the integration, monitoring and control of devices or "things" on a network. It provides a framework for integrating unconventional network devices attached to networks directly, wirelessly or as computer periphery. DCP is a generic, object-oriented protocol which supports connection and connectionless communication between resources. It employs an open ended set of methods for indicating the purpose of a request and builds on the discipline of reference provided by the Uniform Resource Identifier (URI), for indicating the object to which these methods are to be applied. By the typing and negotiation of device data representation, DCP allows applications and devices to be built independently of data representation while maintaining interoperability. It defines an extensible object model that enables the developer to expose objects, properties, methods, and events of a device. Plug-and-play characteristics may be implemented for devices through the reserved user interface and device driver objects. The Device Control Protocol has been designed to provide a natural and comfortable extension of the Internet to "things."
There are numerous ways to use DCP. Here are a few examples:
