Usage Examples

In absence of a complete tutorial, these files can serve as reference implementations for server and client. In order to test them, run ./server.py in one terminal, and use ./clientGET.py and ./clientPUT.py to interact with it.

Client

import logging
import asyncio

from aiocoap import *

logging.basicConfig(level=logging.INFO)

@asyncio.coroutine
def main():
    protocol = yield from Context.create_client_context()

    request = Message(code=GET)
    request.set_request_uri('coap://localhost/time')

    try:
        response = yield from protocol.request(request).response
    except Exception as e:
        print('Failed to fetch resource:')
        print(e)
    else:
        print('Result: %s\n%r'%(response.code, response.payload))

if __name__ == "__main__":
    asyncio.get_event_loop().run_until_complete(main())

import logging
import asyncio

from aiocoap import *

logging.basicConfig(level=logging.INFO)

@asyncio.coroutine
def main():
    """
    Example class which performs single PUT request to localhost
    port 5683 (official IANA assigned CoAP port), URI "/other/block".
    Request is sent 2 seconds after initialization.

    Payload is bigger than 1kB, and thus is sent as several blocks.
    """

    context = yield from Context.create_client_context()

    yield from asyncio.sleep(2)

    payload = b"The quick brown fox jumps over the lazy dog.\n" * 30
    request = Message(code=PUT, payload=payload)
    request.opt.uri_host = '127.0.0.1'
    request.opt.uri_path = ("other", "block")

    response = yield from context.request(request).response

    print('Result: %s\n%r'%(response.code, response.payload))

if __name__ == "__main__":
    asyncio.get_event_loop().run_until_complete(main())

Server

import datetime
import logging

import asyncio

import aiocoap.resource as resource
import aiocoap


class BlockResource(resource.Resource):
    """
    Example resource which supports GET and PUT methods. It sends large
    responses, which trigger blockwise transfer.
    """

    def __init__(self):
        super(BlockResource, self).__init__()
        self.content = ("This is the resource's default content. It is padded "\
                "with numbers to be large enough to trigger blockwise "\
                "transfer.\n" + "0123456789\n" * 100).encode("ascii")

    @asyncio.coroutine
    def render_get(self, request):
        response = aiocoap.Message(code=aiocoap.CONTENT, payload=self.content)
        return response

    @asyncio.coroutine
    def render_put(self, request):
        print('PUT payload: %s' % request.payload)
        self.content = request.payload
        payload = ("I've accepted the new payload. You may inspect it here in "\
                "Python's repr format:\n\n%r"%self.content).encode('utf8')
        return aiocoap.Message(code=aiocoap.CHANGED, payload=payload)


class SeparateLargeResource(resource.Resource):
    """
    Example resource which supports GET method. It uses asyncio.sleep to
    simulate a long-running operation, and thus forces the protocol to send
    empty ACK first.
    """

    def __init__(self):
        super(SeparateLargeResource, self).__init__()
#        self.add_param(resource.LinkParam("title", "Large resource."))

    @asyncio.coroutine
    def render_get(self, request):
        yield from asyncio.sleep(3)

        payload = "Three rings for the elven kings under the sky, seven rings"\
                "for dwarven lords in their halls of stone, nine rings for"\
                "mortal men doomed to die, one ring for the dark lord on his"\
                "dark throne.".encode('ascii')
        return aiocoap.Message(code=aiocoap.CONTENT, payload=payload)

class TimeResource(resource.ObservableResource):
    """
    Example resource that can be observed. The `notify` method keeps scheduling
    itself, and calles `update_state` to trigger sending notifications.
    """
    def __init__(self):
        super(TimeResource, self).__init__()

        self.notify()

    def notify(self):
        self.updated_state()
        asyncio.get_event_loop().call_later(60, self.notify)

    @asyncio.coroutine
    def render_get(self, request):
        payload = datetime.datetime.now().strftime("%Y-%m-%d %H:%M").encode('ascii')
        return aiocoap.Message(code=aiocoap.CONTENT, payload=payload)

#class CoreResource(resource.Resource):
#    """
#    Example Resource that provides list of links hosted by a server.
#    Normally it should be hosted at /.well-known/core
#
#    Notice that self.visible is not set - that means that resource won't
#    be listed in the link format it hosts.
#    """
#
#    def __init__(self, root):
#        resource.Resource.__init__(self)
#        self.root = root
#
#    @asyncio.coroutine
#    def render_get(self, request):
#        data = []
#        self.root.generate_resource_list(data, "")
#        payload = ",".join(data).encode('utf-8')
#        response = aiocoap.Message(code=aiocoap.CONTENT, payload=payload)
#        response.opt.content_format = 40
#        return response

# logging setup

logging.basicConfig(level=logging.INFO)
logging.getLogger("coap-server").setLevel(logging.DEBUG)

def main():
    # Resource tree creation
    root = resource.Site()

    root.add_resource(('.well-known', 'core'), resource.WKCResource(root.get_resources_as_linkheader))

    root.add_resource(('time',), TimeResource())

    root.add_resource(('other', 'block'), BlockResource())

    root.add_resource(('other', 'separate'), SeparateLargeResource())

    asyncio.async(aiocoap.Context.create_server_context(root))

    asyncio.get_event_loop().run_forever()

if __name__ == "__main__":
    main()