From fecb11f2faefa45bd11619f70b611c0f04defae2 Mon Sep 17 00:00:00 2001
From: Alexander Alashkin <alexander.alashkin@cesanta.com>
Date: Thu, 29 Sep 2016 13:34:53 +0200
Subject: [PATCH] Add CoAP server example doc. Closes cesanta/dev#4917
PUBLISHED_FROM=ee7728db61721c0628a00ed702a47f7382ad7cd7
---
docs/coap/server_example.md | 61 ++++++++++++++++++++++++++++++++++++-
1 file changed, 60 insertions(+), 1 deletion(-)
diff --git a/docs/coap/server_example.md b/docs/coap/server_example.md
index 2345755d5..676f537f1 100644
--- a/docs/coap/server_example.md
+++ b/docs/coap/server_example.md
@@ -2,4 +2,63 @@
title: CoAP server example
---
-TBD
+To create a CoAP server, follow this pattern:
+1. Create a listening connection by calling `mg_bind()` or `mg_bind_opt()`
+2. 2. Call `mg_set_protocol_coap()` for that listening connection.
+3. Create an event handler function that handles the following events:
+- `MG_EV_COAP_CON`
+- `MG_EV_COAP_NOC`
+- `MG_EV_COAP_ACK`
+- `MG_EV_COAP_RST`
+
+Here's an example of the simplest CoAP server. Error checking is omitted for the sake of clarity:
+
+```c
+#include "mongoose.h"
+
+static char *s_default_address = "udp://:5683";
+
+static void coap_handler(struct mg_connection *nc, int ev, void *p) {
+ switch (ev) {
+ case MG_EV_COAP_CON: {
+ uint32_t res;
+ struct mg_coap_message *cm = (struct mg_coap_message *) p;
+ printf("CON with msg_id = %d received\n", cm->msg_id);
+ res = mg_coap_send_ack(nc, cm->msg_id);
+ if (res == 0) {
+ printf("Successfully sent ACK for message with msg_id = %d\n",
+ cm->msg_id);
+ } else {
+ printf("Error: %d\n", res);
+ }
+ break;
+ }
+ case MG_EV_COAP_NOC:
+ case MG_EV_COAP_ACK:
+ case MG_EV_COAP_RST: {
+ struct mg_coap_message *cm = (struct mg_coap_message *) p;
+ printf("ACK/RST/NOC with msg_id = %d received\n", cm->msg_id);
+ break;
+ }
+ }
+}
+
+int main(void) {
+ struct mg_mgr mgr;
+ struct mg_connection *nc;
+
+ mg_mgr_init(&mgr, 0);
+
+ nc = mg_bind(&mgr, s_default_address, coap_handler);
+ mg_set_protocol_coap(nc);
+
+ while (1) {
+ mg_mgr_poll(&mgr, 1000);
+ }
+
+ mg_mgr_free(&mgr);
+ return 0;
+}
+```
+
+See full source code at [CoAP server example](https://github.com/cesanta/mongoose/tree/master/examples/coap_server).
--
GitLab