Fixed observe to handle subresources and to always create a fake request for notify GETs

apps/er-coap/er-coap-observe.c

@@ -58,9 +58,9 @@ LIST(observers_list);
 /*---------------------------------------------------------------------------*/
 /*- Internal API ------------------------------------------------------------*/
 /*---------------------------------------------------------------------------*/
-coap_observer_t *
+static coap_observer_t *
-coap_add_observer(uip_ipaddr_t *addr, uint16_t port, const uint8_t *token,
+add_observer(uip_ipaddr_t *addr, uint16_t port, const uint8_t *token,
-                  size_t token_len, const char *uri)
+             size_t token_len, const char *uri, int uri_len)
 {
   /* Remove existing observe relationship, if any. */
   coap_remove_observer_by_uri(addr, port, uri);
@@ -68,7 +68,12 @@ coap_add_observer(uip_ipaddr_t *addr, uint16_t port, const uint8_t *token,
   coap_observer_t *o = memb_alloc(&observers_memb);
 
   if(o) {
-    o->url = uri;
+    int max = sizeof(o->url) - 1;
+    if(max > uri_len) {
+      max = uri_len;
+    }
+    memcpy(o->url, uri, max);
+    o->url[max] = 0;
     uip_ipaddr_copy(&o->addr, addr);
     o->port = port;
     o->token_len = token_len;
@@ -177,18 +182,45 @@ coap_remove_observer_by_mid(uip_ipaddr_t *addr, uint16_t port, uint16_t mid)
 /*---------------------------------------------------------------------------*/
 void
 coap_notify_observers(resource_t *resource)
+{
+  coap_notify_observers_sub(resource, NULL);
+}
+void
+coap_notify_observers_sub(resource_t *resource, const char *subpath)
 {
   /* build notification */
   coap_packet_t notification[1]; /* this way the packet can be treated as pointer as usual */
-  coap_init_message(notification, COAP_TYPE_NON, CONTENT_2_05, 0);
+  coap_packet_t request[1]; /* this way the packet can be treated as pointer as usual */
   coap_observer_t *obs = NULL;
+  int url_len, obs_url_len;
+  char url[COAP_OBSERVER_URL_LEN];
 
-  PRINTF("Observe: Notification from %s\n", resource->url);
+  url_len = strlen(resource->url);
+  strncpy(url, resource->url, COAP_OBSERVER_URL_LEN);
+  if(strlen(url) < COAP_OBSERVER_URL_LEN && subpath != NULL) {
+    strncpy(&url[url_len], subpath, COAP_OBSERVER_URL_LEN - url_len);
+  }
+  /* url now contains the notify URL that needs to match the observer */
+  PRINTF("Observe: Notification from %s\n", url);
+
+  coap_init_message(notification, COAP_TYPE_NON, CONTENT_2_05, 0);
+  /* create a "fake" request for the URI */
+  coap_init_message(request, COAP_TYPE_CON, COAP_GET, 0);
+  coap_set_header_uri_path(request, url);
 
   /* iterate over observers */
+  url_len = strlen(url);
   for(obs = (coap_observer_t *)list_head(observers_list); obs;
       obs = obs->next) {
-    if(obs->url == resource->url) {     /* using RESOURCE url pointer as handle */
+    obs_url_len = strlen(obs->url);
+
+    /* Do a match based on the parent/sub-resource match so that it is
+       possible to do parent-node observe */
+    if((obs_url_len == url_len
+        || (obs_url_len > url_len
+            && (resource->flags & HAS_SUB_RESOURCES)
+            && obs->url[url_len] == '/'))
+       && strncmp(url, obs->url, url_len) == 0) {
       coap_transaction_t *transaction = NULL;
 
       /*TODO implement special transaction for CON, sharing the same buffer to allow for more observers */
@@ -209,7 +241,7 @@ coap_notify_observers(resource_t *resource)
         /* prepare response */
         notification->mid = transaction->mid;
 
-        resource->get_handler(NULL, notification,
+        resource->get_handler(request, notification,
                               transaction->packet + COAP_MAX_HEADER_SIZE,
                               REST_MAX_CHUNK_SIZE, NULL);
 
@@ -237,9 +269,9 @@ coap_observe_handler(resource_t *resource, void *request, void *response)
   if(coap_req->code == COAP_GET && coap_res->code < 128) { /* GET request and response without error code */
     if(IS_OPTION(coap_req, COAP_OPTION_OBSERVE)) {
       if(coap_req->observe == 0) {
-        obs = coap_add_observer(&UIP_IP_BUF->srcipaddr, UIP_UDP_BUF->srcport,
+        obs = add_observer(&UIP_IP_BUF->srcipaddr, UIP_UDP_BUF->srcport,
-                                coap_req->token, coap_req->token_len,
+                           coap_req->token, coap_req->token_len,
-                                resource->url);
+                           coap_req->uri_path, coap_req->uri_path_len);
        if(obs) {
           coap_set_header_observe(coap_res, (obs->obs_counter)++);
           /*

apps/er-coap/er-coap-observe.h

@@ -43,6 +43,8 @@
 #include "er-coap-transactions.h"
 #include "stimer.h"
 
+#define COAP_OBSERVER_URL_LEN 20
+
 typedef struct coap_observable {
   uint32_t observe_clock;
   struct stimer orphan_timer;
@@ -54,7 +56,7 @@ typedef struct coap_observable {
 typedef struct coap_observer {
   struct coap_observer *next;   /* for LIST */
 
-  const char *url;
+  char url[COAP_OBSERVER_URL_LEN];
   uip_ipaddr_t addr;
   uint16_t port;
   uint8_t token_len;
@@ -68,11 +70,6 @@ typedef struct coap_observer {
 } coap_observer_t;
 
 list_t coap_get_observers(void);
-
-coap_observer_t *coap_add_observer(uip_ipaddr_t *addr, uint16_t port,
-                                   const uint8_t *token, size_t token_len,
-                                   const char *url);
-
 void coap_remove_observer(coap_observer_t *o);
 int coap_remove_observer_by_client(uip_ipaddr_t *addr, uint16_t port);
 int coap_remove_observer_by_token(uip_ipaddr_t *addr, uint16_t port,
@@ -83,6 +80,7 @@ int coap_remove_observer_by_mid(uip_ipaddr_t *addr, uint16_t port,
                                 uint16_t mid);
 
 void coap_notify_observers(resource_t *resource);
+void coap_notify_observers_sub(resource_t *resource, const char *subpath);
 
 void coap_observe_handler(resource_t *resource, void *request,
                           void *response);

apps/rest-engine/rest-engine.c

@@ -126,11 +126,11 @@ rest_invoke_restful_service(void *request, void *response, uint8_t *buffer,
   const char *url = NULL;
   int url_len, res_url_len;
 
+  url_len = REST.get_url(request, &url);
   for(resource = (resource_t *)list_head(restful_services);
       resource; resource = resource->next) {
 
     /* if the web service handles that kind of requests and urls matches */
-    url_len = REST.get_url(request, &url);
     res_url_len = strlen(resource->url);
     if((url_len == res_url_len
         || (url_len > res_url_len