/*
* 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
* An abstraction layer for RESTful Web services (Erbium).
* Inspired by RESTful Contiki by Dogan Yazar.
* \author
* Matthias Kovatsch <kovatsch@inf.ethz.ch>
*/
#include <string.h>
#include <stdio.h>
#include "contiki.h"
#include "rest-engine.h"
#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#define PRINT6ADDR(addr) PRINTF("[%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x]", ((uint8_t *)addr)[0], ((uint8_t *)addr)[1], ((uint8_t *)addr)[2], ((uint8_t *)addr)[3], ((uint8_t *)addr)[4], ((uint8_t *)addr)[5], ((uint8_t *)addr)[6], ((uint8_t *)addr)[7], ((uint8_t *)addr)[8], ((uint8_t *)addr)[9], ((uint8_t *)addr)[10], ((uint8_t *)addr)[11], ((uint8_t *)addr)[12], ((uint8_t *)addr)[13], ((uint8_t *)addr)[14], ((uint8_t *)addr)[15])
#define PRINTLLADDR(lladdr) PRINTF("[%02x:%02x:%02x:%02x:%02x:%02x]", (lladdr)->addr[0], (lladdr)->addr[1], (lladdr)->addr[2], (lladdr)->addr[3], (lladdr)->addr[4], (lladdr)->addr[5])
#else
#define PRINTF(...)
#define PRINT6ADDR(addr)
#define PRINTLLADDR(addr)
#endif
PROCESS(rest_engine_process, "REST Engine");
/*---------------------------------------------------------------------------*/
LIST(restful_services);
LIST(restful_periodic_services);
/*---------------------------------------------------------------------------*/
/*- REST Engine API ---------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/**
* \brief Initializes and starts the REST Engine process
*
* This function must be called by server processes before any resources are
* registered through rest_activate_resource().
*/
void
rest_init_engine(void)
{
/* avoid initializing twice */
static uint8_t initialized = 0;
if(initialized) {
PRINTF("REST engine process already running - double initialization?\n");
return;
}
initialized = 1;
list_init(restful_services);
REST.set_service_callback(rest_invoke_restful_service);
/* Start the RESTful server implementation. */
REST.init();
/*Start REST engine process */
process_start(&rest_engine_process, NULL);
}
/*---------------------------------------------------------------------------*/
/**
* \brief Makes a resource available under the given URI path
* \param resource A pointer to a resource implementation
* \param path The URI path string for this resource
*
* The resource implementation must be imported first using the
* extern keyword. The build system takes care of compiling every
* *.c file in the ./resources/ sub-directory (see example Makefile).
*/
void
rest_activate_resource(resource_t *resource, char *path)
{
resource->url = path;
list_add(restful_services, resource);
PRINTF("Activating: %s\n", resource->url);
/* Only add periodic resources with a periodic_handler and a period > 0. */
if(resource->flags & IS_PERIODIC && resource->periodic->periodic_handler
&& resource->periodic->period) {
PRINTF("Periodic resource: %p (%s)\n", resource->periodic,
resource->periodic->resource->url);
list_add(restful_periodic_services, resource->periodic);
}
}
/*---------------------------------------------------------------------------*/
/*- Internal API ------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
list_t
rest_get_resources(void)
{
return restful_services;
}
/*---------------------------------------------------------------------------*/
int
rest_invoke_restful_service(void *request, void *response, uint8_t *buffer,
uint16_t buffer_size, int32_t *offset)
{
uint8_t found = 0;
uint8_t allowed = 1;
resource_t *resource = NULL;
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 */
res_url_len = strlen(resource->url);
if((url_len == res_url_len
|| (url_len > res_url_len
&& (resource->flags & HAS_SUB_RESOURCES)
&& url[res_url_len] == '/'))
&& strncmp(resource->url, url, res_url_len) == 0) {
found = 1;
rest_resource_flags_t method = REST.get_method_type(request);
PRINTF("/%s, method %u, resource->flags %u\n", resource->url,
(uint16_t)method, resource->flags);
if((method & METHOD_GET) && resource->get_handler != NULL) {
/* call handler function */
resource->get_handler(request, response, buffer, buffer_size, offset);
} else if((method & METHOD_POST) && resource->post_handler != NULL) {
/* call handler function */
resource->post_handler(request, response, buffer, buffer_size,
offset);
} else if((method & METHOD_PUT) && resource->put_handler != NULL) {
/* call handler function */
resource->put_handler(request, response, buffer, buffer_size, offset);
} else if((method & METHOD_DELETE) && resource->delete_handler != NULL) {
/* call handler function */
resource->delete_handler(request, response, buffer, buffer_size,
offset);
} else {
allowed = 0;
REST.set_response_status(response, REST.status.METHOD_NOT_ALLOWED);
}
break;
}
}
if(!found) {
REST.set_response_status(response, REST.status.NOT_FOUND);
} else if(allowed) {
/* final handler for special flags */
if(resource->flags & IS_OBSERVABLE) {
REST.subscription_handler(resource, request, response);
}
}
return found & allowed;
}
/*-----------------------------------------------------------------------------------*/
PROCESS_THREAD(rest_engine_process, ev, data)
{
PROCESS_BEGIN();
/* pause to let REST server finish adding resources. */
PROCESS_PAUSE();
/* initialize the PERIODIC_RESOURCE timers, which will be handled by this process. */
periodic_resource_t *periodic_resource = NULL;
for(periodic_resource =
(periodic_resource_t *)list_head(restful_periodic_services);
periodic_resource; periodic_resource = periodic_resource->next) {
if(periodic_resource->periodic_handler && periodic_resource->period) {
PRINTF("Periodic: Set timer for /%s to %lu\n",
periodic_resource->resource->url, periodic_resource->period);
etimer_set(&periodic_resource->periodic_timer,
periodic_resource->period);
}
}
while(1) {
PROCESS_WAIT_EVENT();
if(ev == PROCESS_EVENT_TIMER) {
for(periodic_resource =
(periodic_resource_t *)list_head(restful_periodic_services);
periodic_resource; periodic_resource = periodic_resource->next) {
if(periodic_resource->period
&& etimer_expired(&periodic_resource->periodic_timer)) {
PRINTF("Periodic: etimer expired for /%s (period: %lu)\n",
periodic_resource->resource->url, periodic_resource->period);
/* Call the periodic_handler function, which was checked during adding to list. */
(periodic_resource->periodic_handler)();
etimer_reset(&periodic_resource->periodic_timer);
}
}
}
}
PROCESS_END();
}
/*---------------------------------------------------------------------------*/