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Wiki source code of Set up CoAP Server

Version 1.6 by Xiaoling on 2022/05/17 15:00
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Xiaoling 1.3 1 **~ Contents:**
Xiaoling 1.1 2
Xiaoling 1.3 3 {{toc/}}
Xiaoling 1.1 4
Xiaoling 1.3 5
Xiaoling 1.2 6 = 1. Introduction =
Xiaoling 1.1 7
Xiaoling 1.2 8 (((
9 In this chapter, we set up a CoAP/ MQTT server by using Open Source MQTT Broker : [[EMQX.IO>>url:https://www.emqx.io/]]. And show how to communicate it with CoAP and MQTT.
10 )))
Xiaoling 1.1 11
Xiaoling 1.2 12 (((
13 Below is the network structure. The end device use CoAP to connect our Emqx server via NB-IoT network. EMQ X broker will further process the data for the actually application.
14 )))
Xiaoling 1.1 15
Xiaoling 1.2 16 [[image:https://wiki.dragino.com/images/thumb/2/25/CoAP_1.png/600px-CoAP_1.png||height="219" width="600"]]
Xiaoling 1.1 17
Xiaoling 1.2 18 Network structure
Xiaoling 1.1 19
Xiaoling 1.2 20 = 2. Install CoAP server =
Xiaoling 1.1 21
Xiaoling 1.2 22 Set up example in Ubuntu 18.04
Xiaoling 1.1 23
Xiaoling 1.2 24 (% class="box" %)
25 (((
26 sudo apt-get update
27 sudo apt-get upgrade
28 wget [[https:~~/~~/www.emqx.io/downloads/broker/v3.2.7/emqx-ubuntu18.04-v3.2.7_amd64.deb>>url:https://www.emqx.io/downloads/broker/v3.2.7/emqx-ubuntu18.04-v3.2.7_amd64.deb]]  #download the installation package.
29 sudo dpkg –i emqx-ubuntu18.04-v3.2.4_amd64.deb  #install EMQX
30 emqx start            # Start EMQX service
31 emqx_ctl status   #check if EMQX is running
32 ./bin/emqx_ctl plugins load emqx_coap # Run COAP service
33 )))
Xiaoling 1.1 34
Xiaoling 1.5 35 (((
Xiaoling 1.2 36 (% style="color:red" %)**Notice: CoAP default port use 5683, if you install EMQX in a cloud server, make sure you open the UDP port 5683. So can receive the packets from NB-IoT.**
Xiaoling 1.5 37 )))
Xiaoling 1.1 38
Xiaoling 1.2 39 = 3. Test CoAP Server =
Xiaoling 1.1 40
Xiaoling 1.2 41 == 3.1 Install Copper in Chrome ==
Xiaoling 1.1 42
Xiaoling 1.2 43 (((
44 ~1. Download Copper4Cr from [[https:~~/~~/github.com/mkovatsc/Copper4Cr>>url:https://github.com/mkovatsc/Copper4Cr]] and unpack it.
45 )))
Xiaoling 1.1 46
Xiaoling 1.2 47 (((
48 2. Run install.bat in the directory.
49 )))
Xiaoling 1.1 50
Xiaoling 1.2 51 [[image:https://wiki.dragino.com/images/thumb/4/47/CoAP_Test_1.png/600px-CoAP_Test_1.png||height="191" width="600"]]
52
53 Run install.bat
54
55
56 3. Load the unpacked CoAP APP in Google Chrome:
57
58 [[image:https://wiki.dragino.com/images/thumb/8/8b/CoAP_Test_2.png/600px-CoAP_Test_2.png||height="114" width="600"]]
59
60 Install Copper APP
61
Xiaoling 1.6 62 [[image:https://wiki.dragino.com/images/thumb/7/70/CoAP_Test_3.png/687px-CoAP_Test_3.png||alt="File:CoAP Test 3.png"]]
Xiaoling 1.2 63
64 Install APP Successful
65
66
67 4. Load the unpacked CoAP extension in Google Chrome:
68
69 [[image:https://wiki.dragino.com/images/thumb/6/65/CoAP_Test_4.png/600px-CoAP_Test_4.png||height="154" width="600"]]
70
71 Install Copper Extension
72
73 [[image:https://wiki.dragino.com/images/thumb/9/99/CoAP_Test_5.png/600px-CoAP_Test_5.png||height="183" width="600"]]
74
75 Install Extension Successful
76
77
78 5. Replace the appID in file extension\endpoint\ClientPortChrome.js to Copper (Cu4Cr) Application ID
79
80 [[image:https://wiki.dragino.com/images/thumb/7/7e/CoAP_Test_6.png/600px-CoAP_Test_6.png||height="301" width="600"]]
81
82 Replace ID
83
84
85 6. Open the Copper extension. If you see below message, means install successfully.
86
87 [[image:https://wiki.dragino.com/images/thumb/b/b1/CoAP_Test_7.png/600px-CoAP_Test_7.png||height="323" width="600"]]
88
89 Install Finished
90
91
92 == 3.2 Test CoAP connection ==
93
94 (((
95 Use Chrome Copper externsion to connect to the CoAP server. Input coap:~/~/COAP_SERVER_IP/mqtt/topic0?c=t1 to connect to the MQTT topic0 in CoAP server. Replace COAP_SERVER_IP with your COAP Server IP address, and refer [[here>>url:https://github.com/emqx/emqx-coap]] for the CoAP detail in EMQX. When connection ok, you can see below window.
96 )))
97
98 [[image:https://wiki.dragino.com/images/thumb/0/0c/CoAP_Test_8.png/600px-CoAP_Test_8.png||height="323" width="600"]]
99
100 Connect to CoAP server
101
102
103 == 3.3 Test CoAP Uplink ==
104
105 (((
106 Try to use MQTT.fx to subscribe a the topic (topic0) in the server. And use CoAP to send a message to this topic, we can see the message arrive the topic0 and shown in MQTT.fx.
107 )))
108
109 [[image:https://wiki.dragino.com/images/thumb/b/b0/CoAP_Test_9.png/600px-CoAP_Test_9.png||height="429" width="600"]]
110
111 Use MQTT.fx to subscribe the topic
112
113
114 [[image:https://wiki.dragino.com/images/thumb/3/39/CoAP_Test_10.png/600px-CoAP_Test_10.png||height="323" width="600"]]
115
116 Use CoAP Exension to send a update to CoAP server
117
118
119 [[image:https://wiki.dragino.com/images/thumb/f/fe/CoAP_Test_11.png/600px-CoAP_Test_11.png||height="386" width="600"]]
120
121 MQTT.fx get the update of this topic on CoAP server
122
123
124 == 3.4 Test CoAP Downlink ==
125
Xiaoling 1.3 126 (((
Xiaoling 1.2 127 Try to use MQTT.fx to publish a message to the topic (topic0) in the server. CoAP extension will see this incomming message.
Xiaoling 1.3 128 )))
Xiaoling 1.2 129
130
131 Use MQTT.fx to publish the topic
132
133
134 CoAP extension see the incoming message