From 6e28e95c00218f940979d34da2f662b67e39925e Mon Sep 17 00:00:00 2001 From: Alexandre Abadie Date: Thu, 14 Sep 2017 09:52:28 +0200 Subject: [PATCH] examples/gcoap: update README and add new handlers --- examples/gcoap/README.md | 39 ++++++++++++++++++++++++----- examples/gcoap/gcoap_cli.c | 51 ++++++++++++++++++++++++++++++++------ 2 files changed, 77 insertions(+), 13 deletions(-) diff --git a/examples/gcoap/README.md b/examples/gcoap/README.md index 47209f5f86..9cd7d3b8b2 100644 --- a/examples/gcoap/README.md +++ b/examples/gcoap/README.md @@ -1,19 +1,29 @@ -# gcoap Example +## About -This application provides command line access to gcoap, a high-level API for CoAP messaging. See the [CoAP spec][1] for background, and the Modules>Networking>CoAP topic in the source documentation for detailed usage instructions and implementation notes. +This application provides command line access to gcoap, a high-level API for +CoAP messaging. See the [CoAP spec][1] for background, and the +Modules>Networking>CoAP topic in the source documentation for detailed usage +instructions and implementation notes. We support two setup options for this example: ### Native networking -Build with the standard `Makefile`. Follow the setup [instructions][2] for the gnrc_networking example. + +Build with the standard `Makefile`. Follow the setup [instructions][2] for +the gnrc_networking example. ### SLIP-based border router -Build with `Makefile.slip`. Follow the setup instructions in README-slip.md, which are based on the [SLIP instructions][3] for the gnrc_border_router example. We also plan to provide or reference the ethos/UHCP instructions, but we don't have it working yet. +Build with `Makefile.slip`. Follow the setup instructions in README-slip.md, +which are based on the [SLIP instructions][3] for the gnrc_border_router +example. We also plan to provide or reference the ethos/UHCP instructions, +but we don't have it working yet. ## Example Use -This example uses gcoap as a server on RIOT native. Then we send a request from a libcoap example client on the Linux host. + +This example uses gcoap as a server on RIOT native. Then we send a request +from a libcoap example client on the Linux host. ### Verify setup from RIOT terminal @@ -26,7 +36,10 @@ Expected response: CoAP open requests: 0 ### Query from libcoap example client -gcoap does not provide any output to the CoAP terminal when it handles a request. We recommend use of Wireshark to see the request and response. You also can add some debug output in the endpoint function callback. + +gcoap does not provide any output to the CoAP terminal when it handles a +request. We recommend use of Wireshark to see the request and response. You +also can add some debug output in the endpoint function callback. ./coap-client -N -m get -p 5683 coap://[fe80::1843:8eff:fe40:4eaa%tap0]/.well-known/core @@ -38,6 +51,7 @@ Example response: The response shows the endpoint registered by the gcoap CLI example. ### Send query to libcoap example server + Start the libcoap example server with the command below. ./coap-server @@ -53,6 +67,19 @@ CLI output: ;title="General Info";ct=0,;if="clock";rt="Ticks";title="Internal Clock";ct=0;obs,;ct=0 +## Other available CoAP implementations and applications + +RIOT also provides package imports and test applications for other CoAP +implementations: + +* [Nanocoap](../nanocoap_server): a very lightweight CoAP server based on the + [nanocoap library](https://github.com/kaspar030/sock/tree/master/nanocoap) + implementation + +* [Microcoap](../../tests/pkg_microcoap): another lightweight CoAP server based + on the [microcoap library](https://github.com/1248/microcoap) implementation + + [1]: https://tools.ietf.org/html/rfc7252 "CoAP spec" [2]: https://github.com/RIOT-OS/RIOT/tree/master/examples/gnrc_networking "instructions" [3]: https://github.com/RIOT-OS/RIOT/tree/master/examples/gnrc_border_router "SLIP instructions" diff --git a/examples/gcoap/gcoap_cli.c b/examples/gcoap/gcoap_cli.c index d8dc5d0845..9a3706851c 100644 --- a/examples/gcoap/gcoap_cli.c +++ b/examples/gcoap/gcoap_cli.c @@ -32,11 +32,14 @@ static void _resp_handler(unsigned req_state, coap_pkt_t* pdu, sock_udp_ep_t *remote); static ssize_t _stats_handler(coap_pkt_t* pdu, uint8_t *buf, size_t len); +static ssize_t _riot_board_handler(coap_pkt_t* pdu, uint8_t *buf, size_t len); /* CoAP resources */ static const coap_resource_t _resources[] = { - { "/cli/stats", COAP_GET, _stats_handler }, + { "/cli/stats", COAP_GET | COAP_PUT, _stats_handler }, + { "/riot/board", COAP_GET, _riot_board_handler }, }; + static gcoap_listener_t _listener = { (coap_resource_t *)&_resources[0], sizeof(_resources) / sizeof(_resources[0]), @@ -88,16 +91,50 @@ static void _resp_handler(unsigned req_state, coap_pkt_t* pdu, } /* - * Server callback for /cli/stats. Returns the count of packets sent by the - * CLI. + * Server callback for /cli/stats. Accepts either a GET or a PUT. + * + * GET: Returns the count of packets sent by the CLI. + * PUT: Updates the count of packets. Rejects an obviously bad request, but + * allows any two byte value for example purposes. Semantically, the only + * valid action is to set the value to 0. */ static ssize_t _stats_handler(coap_pkt_t* pdu, uint8_t *buf, size_t len) +{ + /* read coap method type in packet */ + unsigned method_flag = coap_method2flag(coap_get_code_detail(pdu)); + + switch(method_flag) { + case COAP_GET: + gcoap_resp_init(pdu, buf, len, COAP_CODE_CONTENT); + + /* write the response buffer with the request count value */ + size_t payload_len = fmt_u16_dec((char *)pdu->payload, req_count); + + return gcoap_finish(pdu, payload_len, COAP_FORMAT_TEXT); + + case COAP_PUT: + /* convert the payload to an integer and update the internal + value */ + if (pdu->payload_len <= 5) { + char payload[6] = { 0 }; + memcpy(payload, (char *)pdu->payload, pdu->payload_len); + req_count = (uint16_t)strtoul(payload, NULL, 10); + return gcoap_response(pdu, buf, len, COAP_CODE_CHANGED); + } + else { + return gcoap_response(pdu, buf, len, COAP_CODE_BAD_REQUEST); + } + } + + return 0; +} + +static ssize_t _riot_board_handler(coap_pkt_t *pdu, uint8_t *buf, size_t len) { gcoap_resp_init(pdu, buf, len, COAP_CODE_CONTENT); - - size_t payload_len = fmt_u16_dec((char *)pdu->payload, req_count); - - return gcoap_finish(pdu, payload_len, COAP_FORMAT_TEXT); + /* write the RIOT board name in the response buffer */ + memcpy(pdu->payload, RIOT_BOARD, strlen(RIOT_BOARD)); + return gcoap_finish(pdu, strlen(RIOT_BOARD), COAP_FORMAT_TEXT); } static size_t _send(uint8_t *buf, size_t len, char *addr_str, char *port_str)