Nitin B
Published

AWS Parking System

Parking system built using Raspberry Pi 2 with AWS IoT.

BeginnerFull instructions provided4,452
AWS Parking System

Things used in this project

Hardware components

Raspberry Pi 2 Model B
Raspberry Pi 2 Model B
×1
IR sensor
×2
Resistor 10k ohm
Resistor 10k ohm
×4
Male/Female Jumper Wires
Male/Female Jumper Wires
×10

Software apps and online services

AWS IoT
Amazon Web Services AWS IoT
AWS SNS
Amazon Web Services AWS SNS

Story

Read more

Schematics

Schema

Code

Shadow Sample

C/C++
/*
 * Copyright 2010-2015 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */

/**
 * @file shadow_sample.c
 * @brief A simple connected window example demonstrating the use of Thing Shadow
 */

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <unistd.h>

#include <signal.h>
#include <memory.h>
#include <sys/time.h>
#include <limits.h>

#include "aws_iot_log.h"
#include "aws_iot_version.h"
#include "aws_iot_shadow_interface.h"
#include "aws_iot_shadow_json_data.h"
#include "aws_iot_config.h"
#include "aws_iot_mqtt_interface.h"

#include <wiringPi.h>

#define SLOTIN 28
#define SLOTOUT 29


void ShadowUpdateStatusCallback(const char *pThingName, ShadowActions_t action,
		Shadow_Ack_Status_t status, const char *pReceivedJsonDocument,
		void *pContextData) {

	if (status == SHADOW_ACK_TIMEOUT) {
		INFO("Update Timeout--");
	} else if (status == SHADOW_ACK_REJECTED) {
		INFO("Update RejectedXX");
	} else if (status == SHADOW_ACK_ACCEPTED) {
		INFO("Update Accepted !!");
	}
}

void windowActuate_Callback(const char *pJsonString, uint32_t JsonStringDataLen,
		jsonStruct_t *pContext) {
	if (pContext != NULL) {
		INFO("Delta - Window state changed to %d", *(bool *) (pContext->pData));
	}
}

char certDirectory[PATH_MAX + 1] = "../../certs";
char HostAddress[255] = AWS_IOT_MQTT_HOST;
uint32_t port = AWS_IOT_MQTT_PORT;
uint8_t numPubs = 5;

void parseInputArgsForConnectParams(int argc, char** argv) {
	int opt;

	while (-1 != (opt = getopt(argc, argv, "h:p:c:n:"))) {
		switch (opt) {
		case 'h':
			strcpy(HostAddress, optarg);
			DEBUG("Host %s", optarg);
			break;
		case 'p':
			port = atoi(optarg);
			DEBUG("arg %s", optarg);
			break;
		case 'c':
			strcpy(certDirectory, optarg);
			DEBUG("cert root directory %s", optarg);
			break;
		case 'n':
			numPubs = atoi(optarg);
			DEBUG("num pubs %s", optarg);
			break;
		case '?':
			if (optopt == 'c') {
				ERROR("Option -%c requires an argument.", optopt);
			} else if (isprint(optopt)) {
				WARN("Unknown option `-%c'.", optopt);
			} else {
				WARN("Unknown option character `\\x%x'.", optopt);
			}
			break;
		default:
			ERROR("ERROR in command line argument parsing");
			break;
		}
	}

}

#define MAX_LENGTH_OF_UPDATE_JSON_BUFFER 200

int main(int argc, char** argv) {
	IoT_Error_t rc = NONE_ERROR;
	int32_t i = 0;
	int slotInClosed = 0;
	int slotOutClosed = 0;
	int update = 0;

	MQTTClient_t mqttClient;
	aws_iot_mqtt_init(&mqttClient);

	char JsonDocumentBuffer[MAX_LENGTH_OF_UPDATE_JSON_BUFFER];
	size_t sizeOfJsonDocumentBuffer = sizeof(JsonDocumentBuffer)
			/ sizeof(JsonDocumentBuffer[0]);
	char *pJsonStringToUpdate;
	int slots_consumed = 0;

	bool windowOpen = false;
	jsonStruct_t windowActuator;
	windowActuator.cb = windowActuate_Callback;
	windowActuator.pData = &windowOpen;
	windowActuator.pKey = "windowOpen";
	windowActuator.type = SHADOW_JSON_BOOL;

	jsonStruct_t slotHandler;
	slotHandler.cb = NULL;
	slotHandler.pKey = "Slots_filled";
	slotHandler.pData = &slots_consumed;
	slotHandler.type = SHADOW_JSON_INT32;

	char rootCA[PATH_MAX + 1];
	char clientCRT[PATH_MAX + 1];
	char clientKey[PATH_MAX + 1];
	char CurrentWD[PATH_MAX + 1];
	char cafileName[] = AWS_IOT_ROOT_CA_FILENAME;
	char clientCRTName[] = AWS_IOT_CERTIFICATE_FILENAME;
	char clientKeyName[] = AWS_IOT_PRIVATE_KEY_FILENAME;

	parseInputArgsForConnectParams(argc, argv);

	INFO("\nAWS IoT SDK Version(dev) %d.%d.%d-%s\n", VERSION_MAJOR,
			VERSION_MINOR, VERSION_PATCH, VERSION_TAG);

	getcwd(CurrentWD, sizeof(CurrentWD));
	sprintf(rootCA, "%s/%s/%s", CurrentWD, certDirectory, cafileName);
	sprintf(clientCRT, "%s/%s/%s", CurrentWD, certDirectory, clientCRTName);
	sprintf(clientKey, "%s/%s/%s", CurrentWD, certDirectory, clientKeyName);

	DEBUG("Using rootCA %s", rootCA);
	DEBUG("Using clientCRT %s", clientCRT);
	DEBUG("Using clientKey %s", clientKey);

	ShadowParameters_t sp = ShadowParametersDefault;
	sp.pMyThingName = AWS_IOT_MY_THING_NAME;
	sp.pMqttClientId = AWS_IOT_MQTT_CLIENT_ID;
	sp.pHost = HostAddress;
	sp.port = port;
	sp.pClientCRT = clientCRT;
	sp.pClientKey = clientKey;
	sp.pRootCA = rootCA;

	INFO("Shadow Init");
	rc = aws_iot_shadow_init(&mqttClient);

	INFO("Shadow Connect");
	rc = aws_iot_shadow_connect(&mqttClient, &sp);

	if (NONE_ERROR != rc) {
		ERROR("Shadow Connection Error %d", rc);
	}

	rc = aws_iot_shadow_register_delta(&mqttClient, &windowActuator);

	if (NONE_ERROR != rc) {
		ERROR("Shadow Register Delta Error");
	}
	wiringPiSetup();
	pinMode(SLOTIN, INPUT);
	pinMode(SLOTOUT, INPUT);
	pullUpDnControl(SLOTIN, PUD_UP);
	pullUpDnControl(SLOTOUT, PUD_UP);

	// loop and publish a change in slot consumtion
	while (1) {
		if (!digitalRead(SLOTIN)) {
			//INFO("SLOTIN closed");
			slotInClosed = 1;
		}
		if (!digitalRead(SLOTOUT)) {
			//INFO("SLOTOUT closed");
			slotOutClosed = 1;
		}
		if (digitalRead(SLOTIN) && (slotInClosed == 1)) {
			//INFO("SLOTIN Opened");
			slotInClosed = 0;
			update = 1;
			slots_consumed++;

		}
		if (digitalRead(SLOTOUT) && (slotOutClosed == 1)) {
			//INFO("SLOTOUT closed");
			slotOutClosed = 0;
			update = 1;
			if (slots_consumed) {
				slots_consumed--;
			}

		}
		if (update == 1) {
			rc = aws_iot_shadow_yield(&mqttClient, 200);
			INFO("\n=======================================================================================\n");
			INFO("On Device: window state %s", windowOpen ? "true" : "false");
			INFO("Slot consumed %d", slots_consumed);
			rc = aws_iot_shadow_init_json_document(JsonDocumentBuffer,
					sizeOfJsonDocumentBuffer);
			if (rc == NONE_ERROR) {
				rc = aws_iot_shadow_add_reported(JsonDocumentBuffer,
						sizeOfJsonDocumentBuffer, 2, &slotHandler,
						&windowActuator);
				if (rc == NONE_ERROR) {
					rc = aws_iot_finalize_json_document(JsonDocumentBuffer,
							sizeOfJsonDocumentBuffer);
					if (rc == NONE_ERROR) {
						INFO("Update Shadow: %s", JsonDocumentBuffer);
						rc = aws_iot_shadow_update(&mqttClient,
								AWS_IOT_MY_THING_NAME, JsonDocumentBuffer,
								ShadowUpdateStatusCallback, NULL, 4, true);
						if (rc == NONE_ERROR) {
							update = 0;
						}
					}
				}
			}
		}
	}

	return 1;
}

Makefile

Makefile
CC = gcc

#remove @ for no make command prints
DEBUG=@

APP_DIR = .
APP_NAME=shadow_sample
APP_INCLUDE_DIRS += -I $(APP_DIR)
APP_SRC_FILES=$(APP_NAME).c

#IoT client directory


IOT_CLIENT_DIR=../../aws_iot_src

PLATFORM_DIR = $(IOT_CLIENT_DIR)/protocol/mqtt/aws_iot_embedded_client_wrapper/platform_linux/openssl
PLATFORM_COMMON_DIR = $(IOT_CLIENT_DIR)/protocol/mqtt/aws_iot_embedded_client_wrapper/platform_linux/common
SHADOW_SRC_DIR= $(IOT_CLIENT_DIR)/shadow


IOT_INCLUDE_DIRS += -I $(IOT_CLIENT_DIR)/protocol/mqtt
IOT_INCLUDE_DIRS += -I $(IOT_CLIENT_DIR)/protocol/mqtt/aws_iot_embedded_client_wrapper
IOT_INCLUDE_DIRS += -I $(IOT_CLIENT_DIR)/protocol/mqtt/aws_iot_embedded_client_wrapper/platform_linux
IOT_INCLUDE_DIRS += -I $(PLATFORM_COMMON_DIR)
IOT_INCLUDE_DIRS += -I $(PLATFORM_DIR)
IOT_INCLUDE_DIRS += -I $(SHADOW_SRC_DIR)
IOT_INCLUDE_DIRS += -I $(IOT_CLIENT_DIR)/utils
IOT_INCLUDE_DIRS += -I $(IOT_CLIENT_DIR)/shadow

IOT_SRC_FILES += $(IOT_CLIENT_DIR)/protocol/mqtt/aws_iot_embedded_client_wrapper/aws_iot_mqtt_embedded_client_wrapper.c
IOT_SRC_FILES += $(IOT_CLIENT_DIR)/utils/jsmn.c
IOT_SRC_FILES += $(IOT_CLIENT_DIR)/utils/aws_iot_json_utils.c
IOT_SRC_FILES += $(shell find $(SHADOW_SRC_DIR)/ -name '*.c')
IOT_SRC_FILES += $(shell find $(PLATFORM_DIR)/ -name '*.c')
IOT_SRC_FILES += $(shell find $(PLATFORM_COMMON_DIR)/ -name '*.c')

#MQTT Paho Embedded C client directory
MQTT_DIR = ../../aws_mqtt_embedded_client_lib
MQTT_C_DIR = $(MQTT_DIR)/MQTTClient-C/src
MQTT_EMB_DIR = $(MQTT_DIR)/MQTTPacket/src

MQTT_INCLUDE_DIR += -I $(MQTT_EMB_DIR)
MQTT_INCLUDE_DIR += -I $(MQTT_C_DIR)

MQTT_SRC_FILES += $(shell find $(MQTT_EMB_DIR)/ -name '*.c')
MQTT_SRC_FILES += $(MQTT_C_DIR)/MQTTClient.c

#TLS - openSSL
TLS_LIB_DIR = /usr/lib/
TLS_INCLUDE_DIR = -I /usr/include/openssl
EXTERNAL_LIBS += -L$(TLS_LIB_DIR)
LD_FLAG := -ldl -lssl -lcrypto
LD_FLAG += -Wl,-rpath,$(TLS_LIB_DIR)

#Aggregate all include and src directories
INCLUDE_ALL_DIRS += $(IOT_INCLUDE_DIRS) 
INCLUDE_ALL_DIRS += $(MQTT_INCLUDE_DIR) 
INCLUDE_ALL_DIRS += $(TLS_INCLUDE_DIR)
INCLUDE_ALL_DIRS += $(APP_INCLUDE_DIRS)
 
SRC_FILES += $(MQTT_SRC_FILES)
SRC_FILES += $(APP_SRC_FILES)
SRC_FILES += $(IOT_SRC_FILES)

# Logging level control
LOG_FLAGS += -DIOT_DEBUG
LOG_FLAGS += -DIOT_INFO
LOG_FLAGS += -DIOT_WARN
LOG_FLAGS += -DIOT_ERROR

COMPILER_FLAGS += -g -lwiringPi
COMPILER_FLAGS += $(LOG_FLAGS)

MAKE_CMD = $(CC) $(SRC_FILES) $(COMPILER_FLAGS) -o $(APP_NAME) $(EXTERNAL_LIBS) $(LD_FLAG) $(INCLUDE_ALL_DIRS)

all:
	$(DEBUG)$(MAKE_CMD)
	
clean:
	rm -rf $(APP_DIR)/$(APP_NAME)	

Credits

Nitin B

Nitin B

4 projects • 8 followers

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