Wiki source code of Through MQTT to upload data

Version 49.2 by Xiaoling on 2022/05/31 14:38

version	line-number	content
44.2	1	Contents:
	2
1.4	3	{{toc/}}
1.1	4
1.4	5
	6
	7
1.2	8	= 1. What is MQTT API? =
1.1	9
1.5	10	{{{MQTT is a publish/subscribe model that runs over TCP/IP sockets or WebSockets. MQTT over WebSockets can be secured with SSL.}}}
1.1	11
	12
1.2	13	= 2. MQTT Features =
1.1	14
1.2	15	The MQTT protocol runs on TCP / IP or other network protocols and provides an ordered, lossless, bidirectional connection. Features include:
1.1	16
1.2	17	* The publish / subscribe messaging pattern used, which provides one-to-many messaging for decoupling from the application.
	18	* Message-masking mechanism for payload content.
	19	* There are three Quality of Service (QoS) for transmitting messages:
	20	* At most, messages of this level may be lost or duplicated, and message postings depend on the underlying TCP / IP network. That is: <= 1
	21	* At one time, this level will ensure that the message arrives, but the message may be repeated. That is:> = 1
	22	* Only once, make sure the message arrives only once. That is: = 1. In some demanding billing systems, you can use this level Data transfer and protocol exchange is minimized (protocol header only 2 bytes) to reduce network traffic
	23	* Notification mechanism, notify the transmission of both sides when an exception occurs
1.1	24
	25
44.2	26
1.2	27	= 3. What does this example shows? How it works? =
1.1	28
43.3	29	(((
1.2	30	The server we use here is ThingSpeak which has an intuitive chart to show the test result for our test.The ThingSpeak IoT service now supports MQTT subscriptions to receive instant updates when [[ThingSpeak>>url:https://thingspeak.com/]] channel gets updated. The method here is general and can be used with other IoT servers for MQTT connection as well.
43.3	31	)))
1.1	32
3.2	33	[[image:image-20220531135402-1.png]]
1.1	34
1.2	35	Message Queuing Telemetry Transport
1.1	36
	37
3.2	38	[[image:image-20220531135449-2.png]]
	39
1.2	40	working principle
1.1	41
3.2	42
4.2	43	[[image:image-20220531135521-3.png]]
1.2	44
43.3	45	(((
1.2	46	Schematic diagram: uplink.In this section, we will try to program LG01 to uplink data to ThingSpeak. The data flow in this example.We have already tried ① and ② in the above simple LoRa example. Now we will try the step ③ first, after it work as expect, we will integrate these three steps together for a complete uplink example.
43.3	47	)))
1.2	48
4.2	49
	50
5.2	51	[[image:image-20220531135607-4.png]]
1.2	52
43.3	53	(((
1.2	54	Schematic diagram:downlink.In this section, we will try to program LG01 to fetch download data from ThingSpeak, then broadcast this data to local LoRa network. The end node will get this message and check if they need to do something. Similar with Uplink Example, we will first try to do it in PC, then do it in Linux side, and finally integrate it with LoRa.
43.3	55	)))
1.2	56
43.3	57	(((
1.2	58	MQTT agreement to achieve the need: client and server There are three identities in the MQTT protocol: Publish, Broker (server), Subscribe. Among them, the publisher and the subscriber of the message are all clients, the broker is the server, and the publisher can be both the subscriber and the subscriber. MQTT transmission of information is divided into: Topic and payload in two parts Topic, can be understood as the type of message subscribers Subscribe, you will receive the theme of the message content (payload) The payload, which can be understood as the content of the message, refers to the specific content to be used by the subscribers.
43.3	59	)))
1.2	60
43.3	61	(((
1.2	62	To use the server, we need to register an account on [[ThingSpeak>>url:https://thingspeak.com/]] . Then create a channel and type the channel info. As shown below, the Channel ID is the unique ID to store our data in [[ThingSpeak>>url:https://thingspeak.com/]] .
43.3	63	)))
1.2	64
	65
44.3	66
1.2	67	= 4. Preparation =
	68
	69	== 4.1 Hardware ==
	70
6.2	71	1. [[image:image-20220531135650-5.png]](((
1.2	72	Listening on the LoRa wireless channel, while there is new LoRa packet arrives, parse it and send out to IoT Server.
6.2	73
	74
	75
1.2	76	)))
7.2	77	1. [[image:image-20220531135750-6.png]](((
1.2	78	The LoRa End node keeps getting temperature and humidity from the sensor and sends out via LoRa periodically.
	79	)))
	80
	81	== 4.2 Software ==
	82
	83	1. [[4.3.4 version>>url:http://www.dragino.com/downloads/index.php?dir=motherboards/ms14/Firmware/IoT/]]
	84	1. [[MQTT_Client>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/IoTServer/ThingSpeak/MQTT_Client]]
	85	1. [[MQTT_Simple_Server MQTT_Simeple_Server>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/LoRa/MQTT_Simple_Server]]
	86	1. [[DHTlib>>url:https://github.com/goodcheney/Lora/blob/patch-1/Lora%20Shield/Examples/DHTlib.zip]]
	87
44.4	88
	89
1.2	90	== 4.3 Server(For example) ==
	91
	92	* [[ThingSpeak>>url:https://thingspeak.com/]]
	93
44.5	94
	95
1.3	96	== 4.4 Configure IoT Server ==
1.2	97
	98	* Need this keys:
	99
9.2	100	1. [[image:image-20220531140054-8.png]](((
1.2	101	Channel ID,Write API Key
8.3	102
	103
	104
1.2	105	)))
14.2	106	1. [[image:image-20220531140326-13.png]](((
1.2	107	Account->My Profile,MQTT API Key
10.2	108
	109
	110
1.2	111	)))
	112	1. (((
14.2	113	[[image:image-20220531140304-12.png]]
44.6	114
	115
	116
1.2	117	)))
	118
1.3	119	== 4.5 Configure LG01 settings ==
1.2	120
44.7	121
1.2	122	Tips:Please confirm that your LG01 version is 4.3.3.
	123
14.2	124	[[image:image-20220531140248-11.png]]
1.2	125
19.3	126	Overview
1.2	127
14.3	128
	129
15.2	130	[[image:image-20220531140425-14.png]]
1.2	131
19.3	132	Senosor->IOT Server
1.2	133
15.2	134
16.2	135	[[image:image-20220531140458-15.png]]
1.2	136
19.3	137	MQTT->Configure MQTT Server
1.2	138
16.2	139
	140
17.2	141	[[image:image-20220531140538-16.png]]
1.2	142
19.3	143	MQTT->MQTT Channel
1.2	144
17.2	145
	146
18.2	147	[[image:image-20220531140611-17.png]]
1.2	148
19.3	149	Sensor->LoRa/LoraWAN
1.2	150
18.2	151
	152
19.2	153	[[image:image-20220531140651-18.png]]
1.2	154
19.3	155	Configure network access.Network->Internet Access
1.2	156
	157
1.3	158	== 4.6 Try MQTT API call with LG01 Linux command ==
1.2	159
1.3	160	=== 4.6.1 Input the command at the console ===
1.2	161
21.2	162	1. [[image:image-20220531140811-19.png]](((
1.2	163	Open this Application.
21.2	164
	165
1.2	166	)))
21.2	167	1. [[image:image-20220531140842-20.png]](((
1.2	168	Input passward(dragino).After into the console.
21.2	169
	170
1.2	171	)))
22.2	172	1. [[image:image-20220531140915-21.png]](((
1.2	173	First, we need to make sure the LG01 has internet access. We can log in the SSH and ping an Internet address and see if it get through. As below
22.3	174
	175
1.2	176	)))
23.2	177	1. [[image:image-20220531140955-22.png]](((
1.2	178	LG01 has built-in Linux tool mosquitto. It is a very powerful tool for http communication. We can use this tool to handle MQTT API call in LG01. Input this command and replace your keys.
23.2	179
	180
	181
1.2	182	)))
24.2	183	1. [[image:image-20220531141026-23.png]](((
1.2	184	Go to Server check out result.We success to use LG01 to uplink data to ThingSpeak,the mosquitto_pub command is executed in the Linux side, finally, we will have to call mosquitto_pub command with sensor data variable in Arduino side. This is through the process class in Arduino and we will show it in the final sketch.
	185	)))
	186
	187	* This command:
	188
24.3	189	(% class="box infomessage" %)
	190	(((
	191	mosquitto_pub -h mqtt.thingspeak.com -p 1883 -u dragino -P UZ4NGHKJMKS9WR5E -i dragino_Client -t channels/399171/publish/A4NNF6G8G63JOIUV -m "field1=23.5&field2=57.5&status=MQTTPUBLISH"
	192	)))
1.2	193
	194	* Need replace:
	195
24.3	196	(% class="box infomessage" %)
	197	(((
	198	**UZ4NGHKJMKS9WR5E ~/~/MQTT API
	199	399171 ~/~/Channel ID
	200	A4NNF6G8G63JOIUV ~/~/Write API Key**
	201	)))
1.2	202
	203
1.3	204	=== 4.6.2 Input the command at the console(LG01 new version:4.3.4) ===
1.2	205
25.2	206	1. [[image:image-20220531141150-24.png]](((
1.2	207	Open this Application.
25.2	208
	209
	210
1.2	211	)))
27.2	212	1. (((
	213	[[image:image-20220531141400-27.png]]
	214
1.2	215	Check the settings.
27.2	216
	217
	218
1.2	219	)))
28.2	220	1. (((
29.2	221	[[image:image-20220531141601-30.png]]
	222
1.2	223	input this command.
27.2	224
	225
	226
1.2	227	)))
28.2	228	1. [[image:image-20220531141515-29.png]](((
1.2	229	Check the result.
28.2	230
	231
	232
1.2	233	)))
	234
1.3	235	== 4.7 Updata data to Server(Through MQTT) ==
1.2	236
	237	* This version of Sketch implements these features:
	238
	239	1. Read the LG01 configuration information from Linux.
	240	1. Receive the LoRa node data and store the data in the /tmp/iot/channels
	241	1. Send reply after then receive LoRa node data.
	242	1. Sketch will write active content to /tmp/iot/status periodically (every 5 minutes).(Watchdog feature)
	243
49.2	244	1. [[image:image-20220531143822-49.png]](((
1.2	245	Open the sketch [[MQTT_Simple_Server>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/LoRa/MQTT_Simple_Server]].(Board:Dragino Yun + UNO or LG01/OLG01,Port:Network ports.)and upload.
30.2	246
	247
	248
1.2	249	)))
31.2	250	1. [[image:image-20220531141800-32.png]](((
1.2	251	Open Serial monitor.
31.2	252
	253
	254
1.2	255	)))
48.2	256	1. [[image:image-20220531143748-48.png]](((
1.2	257	Open the Sketch [[MQTT_Client>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/IoTServer/ThingSpeak/MQTT_Client]]. (Board:Arduino/Genuino Uno.Port:Serial ports.)and upload.
32.2	258
	259
	260
1.2	261	)))
33.2	262	1. [[image:image-20220531141927-34.png]](((
1.2	263	Open Serial monitor.
33.2	264
	265
	266
1.2	267	)))
	268	1. Go to IoT Server to check the result.
	269	1. (((
47.2	270	[[image:image-20220531143707-47.png]]
34.2	271
35.2	272
34.2	273
1.2	274	)))
	275	1. (((
46.2	276	[[image:image-20220531143632-46.png]]
35.3	277
	278
	279
1.2	280	)))
	281
1.3	282	= 5. FAQ =
1.2	283
1.3	284	== 5.1 Configure to support general mqtt server ==
1.2	285
	286	First, try to run mosquitto_pub in Linux console to send a data to MQTT server.
	287
	288	For example: for ThingSpeak, a MQTT publish command is:
	289
36.2	290	(% class="box infomessage" %)
	291	(((
	292	mosquitto_pub -h mqtt.thingspeak.com -p 1883 -u dragino -P QZXTAKE88V3S7O2J -i dragino_Client -t channels/200893/publish/B9Z0R25QNVEBKIFY -m "field1=34&field2=89&status=MQTTPUBLISH"
	293	)))
1.2	294
	295	What now we need to put in the LG01 is how to combine this command.
	296
	297	1. LG01 web console -> Sensor -> MQTT
	298	1. Choose general Server
36.2	299	1. [[image:image-20220531142342-37.png]](((
1.2	300	Refer to your server to fill in.
36.2	301
	302
	303
1.2	304	)))
37.2	305	1. [[image:image-20220531142447-38.png]](((
1.2	306	Ex:ThingSpeak Server
37.2	307
	308
1.2	309	)))
	310
	311	According to MQTT commands: mosquitto_pub, we need to put
	312
	313	* server[-h] : mqtt.thingspeak.com
	314	* port[-p] : 1883
	315	* User Name[-u]: dragino
	316	* Password[-P]:QZXTAKE88V3S7O2J
	317	* Client ID[-i]: dragino_Client
	318	* topic_format[-t]: channels/CHANNEL/publish/WRITE_API
	319	* data_format[-m]: DATA&status=MQTTPUBLISH
	320
	321	In the mqtt script, the upper CHANNEL will be replaced by the parameter (remote channel in IoT server). and the WRITE_API will be replaced by the settings in write api key. the DATA will be replaced by the value stored in the /var/iot/channels/LOCAL_CHANNEL file.
	322
	323	MQTT script will keep checking the files in /var/iot/channels/ . If it find a match Local channel, then the MQTT script will send out the data of this local channel to a remote channel according to the setting above.
	324
	325	User can also enable MQTT debug in the LG01 ~-~-> IoT Server settings and run logread in Linux console to see how the mqtt command is compose. below is an example:
	326
38.2	327	[[image:image-20220531142525-39.png]]
1.2	328
	329	MQTT Logread example
	330
	331
1.3	332	== 5.2 What is Watchdog feature? ==
1.2	333
	334	LG01 for 4.3.3 version,we have added watchdog feature. In order to avoid the gateway running process will get stuck. So add writing action on every times.
	335
39.2	336	* [[image:image-20220531142558-40.png]](((
1.2	337	Enable Sensor->Micro-Controller settings
39.3	338
	339
	340
1.2	341	)))
40.2	342	* [[image:image-20220531142629-41.png]](((
1.2	343	Open the sketch [[MQTT_Simple_Server>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/LoRa/MQTT_Simple_Server]].(Board:Dragino Yun + UNO or LG01/OLG01,Port:Network ports.)and upload.
40.2	344
	345
	346
1.2	347	)))
41.2	348	* [[image:image-20220531142659-42.png]](((
1.2	349	Each time the function loops, it uses the watchdog function once.
41.2	350
	351
	352
1.2	353	)))
42.2	354	* [[image:image-20220531142720-43.png]](((
1.2	355	Open SSH and check watchdog result.If the result change constantly,the feature enable successfully.
42.2	356
	357
	358
1.2	359	)))
43.2	360	* [[image:image-20220531142748-44.png]](((
1.2	361	If the time doesnt's change,you can refer it to calculate for checking status.
	362	)))
	363
44.1	364	(% class="wikigeneratedid" id="H" %)
	365

Wiki source code of Through MQTT to upload data

Applications

Navigation