Updated to CoAP Proposed Standard and removed draft versions.

examples/er-rest-example/resources/res-event.c

@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) 2013, Institute for Pervasive Computing, ETH Zurich
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file is part of the Contiki operating system.
+ */
+
+/**
+ * \file
+ *      Example resource
+ * \author
+ *      Matthias Kovatsch <kovatsch@inf.ethz.ch>
+ */
+
+#include <string.h>
+#include "rest-engine.h"
+#include "er-coap.h"
+
+#define DEBUG   DEBUG_NONE
+#include "net/uip-debug.h"
+
+static void res_get_handler(void* request, void* response, uint8_t *buffer, uint16_t preferred_size, int32_t *offset);
+static void res_event_handler();
+
+/*
+ * Example for an event resource.
+ * Additionally takes a period parameter that defines the interval to call [name]_periodic_handler().
+ * A default post_handler takes care of subscriptions and manages a list of subscribers to notify.
+ */
+EVENT_RESOURCE(res_event,
+    "title=\"Event demo\";obs",
+    res_get_handler,
+    NULL,
+    NULL,
+    NULL,
+    res_event_handler);
+
+/*
+ * Use local resource state that is accessed by res_get_handler() and altered by res_event_handler() or PUT or POST.
+ */
+static int32_t event_counter = 0;
+
+static void
+res_get_handler(void* request, void* response, uint8_t *buffer, uint16_t preferred_size, int32_t *offset)
+{
+  REST.set_header_content_type(response, REST.type.TEXT_PLAIN);
+  REST.set_response_payload(response, buffer, snprintf((char *)buffer, preferred_size, "EVENT %lu", event_counter));
+
+  /* A post_handler that handles subscriptions/observing will be called for periodic resources by the framework. */
+}
+
+/*
+ * Additionally, res_event_handler must be implemented for each EVENT_RESOURCE.
+ * It is called through <res_name>.trigger(), usually from the server process.
+ */
+static void
+res_event_handler()
+{
+  /* Do the update triggered by the event here, e.g., sampling a sensor. */
+  ++event_counter;
+
+  /* Usually a condition is defined under with subscribers are notified, e.g., event was above a threshold. */
+  if (1) {
+    PRINTF("TICK %u for /%s\n", event_counter, res_event.url);
+
+    /* Notify the registered observers which will trigger the res_get_handler to create the response. */
+    REST.notify_subscribers(&res_event);
+  }
+}