Adafruit_MQTT_Library/Adafruit_MQTT.h
2015-07-27 20:32:38 +02:00

212 lines
7.3 KiB
C++

// The MIT License (MIT)
//
// Copyright (c) 2015 Adafruit Industries
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
#ifndef _ADAFRUIT_MQTT_H_
#define _ADAFRUIT_MQTT_H_
#if ARDUINO >= 100
#include "Arduino.h"
#else
#include "WProgram.h"
#endif
// Uncomment/comment to turn on/off debug output messages.
//#define MQTT_DEBUG
// Set where debug messages will be printed.
#define DEBUG_PRINTER Serial
// Define actual debug output functions when necessary.
#ifdef MQTT_DEBUG
#define DEBUG_PRINT(...) { DEBUG_PRINTER.print(__VA_ARGS__); }
#define DEBUG_PRINTLN(...) { DEBUG_PRINTER.println(__VA_ARGS__); }
#define DEBUG_PRINTBUFFER(buffer, len) { printBuffer(buffer, len); }
#else
#define DEBUG_PRINT(...) {}
#define DEBUG_PRINTLN(...) {}
#define DEBUG_PRINTBUFFER(buffer, len) {}
#endif
#define MQTT_PROTOCOL_LEVEL 3
#define MQTT_CTRL_CONNECT 0x01
#define MQTT_CTRL_CONNECTACK 0x02
#define MQTT_CTRL_PUBLISH 0x03
#define MQTT_CTRL_SUBSCRIBE 0x08
#define MQTT_CTRL_SUBACK 0x09
#define MQTT_CTRL_PINGREQ 0x0C
#define MQTT_CTRL_PINGRESP 0x0D
#define MQTT_QOS_1 0x1
#define MQTT_QOS_0 0x0
#define CONNECT_TIMEOUT_MS 3000
#define PUBLISH_TIMEOUT_MS 500
#define PING_TIMEOUT_MS 500
// Adjust as necessary, in seconds. Default to 5 minutes.
#define MQTT_CONN_KEEPALIVE 300
// Largest full packet we're able to send.
// Need to be able to store at least ~90 chars for a connect packet with full
// 23 char client ID.
#define MAXBUFFERSIZE (125)
#define MQTT_CONN_USERNAMEFLAG 0x80
#define MQTT_CONN_PASSWORDFLAG 0x40
#define MQTT_CONN_WILLRETAIN 0x20
#define MQTT_CONN_WILLQOS 0x08
#define MQTT_CONN_WILLFLAG 0x04
#define MQTT_CONN_CLEANSESSION 0x02
// how many subscriptions we want to be able to
// track
#define MAXSUBSCRIPTIONS 5
// how much data we save in a subscription object
// eg max-subscription-payload-size
#define SUBSCRIPTIONDATALEN 20
extern void printBuffer(uint8_t *buffer, uint8_t len);
class Adafruit_MQTT_Subscribe; // forward decl
class Adafruit_MQTT {
public:
Adafruit_MQTT(const char *server, uint16_t port, const char *cid,
const char *user, const char *pass);
virtual ~Adafruit_MQTT() {}
// Connect to the MQTT server. Returns 0 on success, otherwise an error code
// that indicates something went wrong:
// -1 = Error connecting to server
// 1 = Wrong protocol
// 2 = ID rejected
// 3 = Server unavailable
// 4 = Bad username or password
// 5 = Not authenticated
// 6 = Failed to subscribe
// Use connectErrorString() to get a printable string version of the
// error.
int8_t connect();
// Return a printable string version of the error code returned by
// connect(). This returns a __FlashStringHelper*, which points to a
// string stored in flash, but can be directly passed to e.g.
// Serial.println without any further processing.
const __FlashStringHelper* connectErrorString(int8_t code);
// Disconnect from the MQTT server. Returns true if disconnected, false
// otherwise.
virtual bool disconnect() = 0; // Subclasses need to fill this in!
// Return true if connected to the MQTT server, otherwise false.
virtual bool connected() = 0; // Subclasses need to fill this in!
// Publish a message to a topic using the specified QoS level. Returns true
// if the message was published, false otherwise.
bool publish(const char *topic, const char *payload, uint8_t qos);
// Add a subscription to receive messages for a topic. Returns true if the
// subscription could be added or was already present, false otherwise.
// Must be called before connect(), subscribing after the connection
// is made is not currently supported.
bool subscribe(Adafruit_MQTT_Subscribe *sub);
// Check if any subscriptions have new messages. Will return a reference to
// an Adafruit_MQTT_Subscribe object which has a new message. Should be called
// in the sketch's loop function to ensure new messages are recevied. Note
// that subscribe should be called first for each topic that receives messages!
Adafruit_MQTT_Subscribe *readSubscription(int16_t timeout=0);
// Ping the server to ensure the connection is still alive. Returns true if
// successful, otherwise false.
bool ping(uint8_t t);
protected:
// Interface that subclasses need to implement:
// Connect to the server and return true if successful, false otherwise.
virtual bool connectServer() = 0;
// Send data to the server specified by the buffer and length of data.
virtual bool sendPacket(uint8_t *buffer, uint8_t len) = 0;
// Read MQTT packet from the server. Will read up to maxlen bytes and store
// the data in the provided buffer. Waits up to the specified timeout (in
// milliseconds) for data to be available. If checkForValidPubPacket is true
// then the received data is verified to make sure it's a complete packet.
virtual uint16_t readPacket(uint8_t *buffer, uint8_t maxlen, int16_t timeout,
bool checkForValidPubPacket = false) = 0;
// Shared state that subclasses can use:
const char *servername;
int16_t portnum;
const char *clientid;
const char *username;
const char *password;
uint8_t buffer[MAXBUFFERSIZE]; // one buffer, used for all incoming/outgoing
private:
Adafruit_MQTT_Subscribe *subscriptions[MAXSUBSCRIPTIONS];
// Functions to generate MQTT packets.
uint8_t connectPacket(uint8_t *packet);
uint8_t publishPacket(uint8_t *packet, const char *topic, const char *payload, uint8_t qos);
uint8_t subscribePacket(uint8_t *packet, const char *topic, uint8_t qos);
uint8_t pingPacket(uint8_t *packet);
};
class Adafruit_MQTT_Publish {
public:
Adafruit_MQTT_Publish(Adafruit_MQTT *mqttserver, const char *feed, uint8_t qos = 0);
bool publish(const char *s);
bool publish(double f, uint8_t precision=2); // Precision controls the minimum number of digits after decimal.
// This might be ignored and a higher precision value sent.
bool publish(int32_t i);
bool publish(uint32_t i);
private:
Adafruit_MQTT *mqtt;
const char *topic;
uint8_t qos;
};
class Adafruit_MQTT_Subscribe {
public:
Adafruit_MQTT_Subscribe(Adafruit_MQTT *mqttserver, const char *feedname, uint8_t q=0);
bool setCallback(void (*callback)(char *));
const char *topic;
uint8_t qos;
uint8_t * lastread[SUBSCRIPTIONDATALEN];
private:
Adafruit_MQTT *mqtt;
};
#endif