osd-contiki/examples/er-rest-example/README.md
2013-03-26 23:15:37 +01:00

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A Quick Introduction to the Erbium (Er) REST Engine
===================================================
EXAMPLE FILES
-------------
- er-example-server.c: A RESTful server example showing how to use the REST
layer to develop server-side applications (at the moment only CoAP is
implemented for the REST Engine).
- er-example-client.c: A CoAP client that polls the /actuators/toggle resource
every 10 seconds and cycles through 4 resources on button press (target
address is hard-coded).
- er-plugtest-server.c: The server used for draft compliance testing at ETSI
IoT CoAP Plugtest in Paris, France, March 2012 (configured for minimal-net).
PRELIMINARIES
-------------
- Make sure rpl-border-router has the same stack and fits into mote memory:
You can disable RDC in border-router project-conf.h (not really required as BR keeps radio turned on).
#undef NETSTACK_CONF_RDC
#define NETSTACK_CONF_RDC nullrdc_driver
- For convenience, define the Cooja addresses in /etc/hosts
aaaa::0212:7401:0001:0101 cooja1
aaaa::0212:7402:0002:0202 cooja2
...
- Get the Copper (Cu) CoAP user-agent from
[https://addons.mozilla.org/en-US/firefox/addon/copper-270430](https://addons.mozilla.org/en-US/firefox/addon/copper-270430)
- Optional: Save your target as default target
make TARGET=sky savetarget
COOJA HOWTO
-----------
###Server only:
make TARGET=cooja server-only.csc
Open new terminal
make connect-router-cooja
- Start Copper and discover resources at coap://cooja2:5683/
- Choose "Click button on Sky 2" from the context menu of mote 2 (server) after
requesting /test/separate
- Do the same when observing /test/event
###With client:
make TARGET=cooja server-client.csc
Open new terminal
make connect-router-cooja
- Wait until red LED toggles on mote 2 (server)
- Choose "Click button on Sky 3" from the context menu of mote 3 (client) and
watch serial output
TMOTES HOWTO
------------
###Server:
1. Connect two Tmote Skys (check with $ make TARGET=sky sky-motelist)
make TARGET=sky er-example-server.upload MOTE=2
make TARGET=sky login MOTE=2
2. Press reset button, get address, abort with Ctrl+C:
Line: "Tentative link-local IPv6 address fe80:0000:0000:0000:____:____:____:____"
cd ../ipv6/rpl-border-router/
make TARGET=sky border-router.upload MOTE=1
make connect-router
For a BR tty other than USB0:
make connect-router-port PORT=X
3. Start Copper and discover resources at:
coap://[aaaa::____:____:____:____]:5683/
### Add a client:
1. Change the hard-coded server address in er-example-client.c to aaaa::____:____:____:____
2. Connect a third Tmote Sky
make TARGET=sky er-example-client.upload MOTE=3
MINIMAL-NET HOWTO
-----------------
With the target minimal-net you can test your CoAP applications without
constraints, i.e., with large buffers, debug output, memory protection, etc.
The er-plugtest-server is thought for the minimal-net platform, as it requires
an 1280-byte IP buffer and 1024-byte blocks.
make TARGET=minimal-net er-plugtest-server
sudo ./er-plugtest-server.minimal-net
Open new terminal
make connect-minimal
- Start Copper and discover resources at coap://[fdfd::ff:fe00:10]:5683/
- You can enable the ETSI Plugtest menu in Copper's preferences
Under Windows/Cygwin, WPCAP might need a patch in
<cygwin>\usr\include\w32api\in6addr.h:
21,23c21
< #ifdef __INSIDE_CYGWIN__
< uint32_t __s6_addr32[4];
< #endif
---
> u_int __s6_addr32[4];
36d33
< #ifdef __INSIDE_CYGWIN__
39d35
< #endif
DETAILS
-------
Erbium currently implements draft 13. Central features are commented in
er-example-server.c. In general, apps/er-coap-13 supports:
- All draft 13 header options
- CON Retransmissions (note COAP_MAX_OPEN_TRANSACTIONS)
- Blockwise Transfers (note REST_MAX_CHUNK_SIZE, see er-plugtest-server.c for
Block1 uploads)
- Separate Responses (no rest_set_pre_handler() required anymore, note
coap_separate_accept(), _reject(), and _resume())
- Resource Discovery
- Observing Resources (see EVENT_ and PRERIODIC_RESOURCE, note
COAP_MAX_OBSERVERS)
REST IMPLEMENTATIONS
--------------------
The Makefile uses WITH_COAP to configure different implementations for the
Erbium (Er) REST Engine.
- WITH_COAP=13 uses Erbium CoAP 13 apps/er-coap-13/. The default port for
coap-13 is 5683.
- WITH_COAP=12 uses Erbium CoAP 12 apps/er-coap-12/. The default port for
coap-12 is 5683.
- WITH_COAP=7 uses Erbium CoAP 08 apps/er-coap-07/. The default port for
coap-07/-08 is 5683.
- WITH_COAP=3 uses Erbium CoAP 03 apps/er-coap-03/. The default port for
coap-03 is 61616. er-coap-03 produces some warnings, as it not fully
maintained anymore.
- WITH_COAP=0 is a stub to link an Erbium HTTP engine that uses the same
resource abstraction (REST.x() functions and RESOURCE macros.
TODOs
-----
- Dedicated Observe buffers
- Optimize message struct variable access (directly access struct without copying)
- Observe client
- Multiple If-Match ETags
- (Message deduplication)