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Wiki source code of Set up CoAP Server

Version 15.1 by Xiaoling on 2022/05/30 09:18
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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 2.2 16 [[image:image-20220530084843-1.png]]
Xiaoling 1.1 17
Xiaoling 1.2 18 Network structure
Xiaoling 1.1 19
Xiaoling 2.2 20
Xiaoling 1.2 21 = 2. Install CoAP server =
Xiaoling 1.1 22
Xiaoling 1.2 23 Set up example in Ubuntu 18.04
Xiaoling 1.1 24
Xiaoling 1.2 25 (% class="box" %)
26 (((
27 sudo apt-get update
28 sudo apt-get upgrade
29 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.
30 sudo dpkg –i emqx-ubuntu18.04-v3.2.4_amd64.deb  #install EMQX
31 emqx start            # Start EMQX service
32 emqx_ctl status   #check if EMQX is running
33 ./bin/emqx_ctl plugins load emqx_coap # Run COAP service
34 )))
Xiaoling 1.1 35
Xiaoling 1.5 36 (((
Xiaoling 1.2 37 (% 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 6.2 38
39
Xiaoling 1.5 40 )))
Xiaoling 1.1 41
Xiaoling 1.2 42 = 3. Test CoAP Server =
Xiaoling 1.1 43
Xiaoling 1.2 44 == 3.1 Install Copper in Chrome ==
Xiaoling 1.1 45
Xiaoling 1.2 46 (((
47 ~1. Download Copper4Cr from [[https:~~/~~/github.com/mkovatsc/Copper4Cr>>url:https://github.com/mkovatsc/Copper4Cr]] and unpack it.
48 )))
Xiaoling 1.1 49
Xiaoling 1.2 50 (((
51 2. Run install.bat in the directory.
Xiaoling 6.2 52
53 [[image:image-20220530085327-2.png]]
Xiaoling 1.2 54 )))
Xiaoling 1.1 55
Xiaoling 1.2 56 Run install.bat
57
58
59 3. Load the unpacked CoAP APP in Google Chrome:
60
Xiaoling 6.2 61 [[image:image-20220530085423-3.png]]
Xiaoling 1.2 62
63 Install Copper APP
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Xiaoling 6.2 66 [[image:image-20220530085531-4.png]]
67
Xiaoling 1.2 68 Install APP Successful
69
70
71 4. Load the unpacked CoAP extension in Google Chrome:
72
Xiaoling 7.3 73 [[image:image-20220530085638-5.png||height="338" width="1320"]]
Xiaoling 1.2 74
75 Install Copper Extension
76
Xiaoling 15.1 77
Xiaoling 7.2 78 [[image:image-20220530090104-7.png]]
Xiaoling 1.2 79
80 Install Extension Successful
81
82
83 5. Replace the appID in file extension\endpoint\ClientPortChrome.js to Copper (Cu4Cr) Application ID
84
Xiaoling 9.2 85 [[image:image-20220530090444-10.png]]
Xiaoling 1.2 86
87 Replace ID
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89
90 6. Open the Copper extension. If you see below message, means install successfully.
91
Xiaoling 8.4 92 [[image:image-20220530090404-9.png||height="658" width="1238"]]
Xiaoling 1.2 93
94 Install Finished
95
96
97 == 3.2 Test CoAP connection ==
98
99 (((
100 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.
Xiaoling 10.2 101
102 [[image:image-20220530090848-13.png||height="616" width="1154"]]
Xiaoling 1.2 103 )))
104
105 Connect to CoAP server
106
Xiaoling 9.2 107
Xiaoling 1.2 108 == 3.3 Test CoAP Uplink ==
109
110 (((
111 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.
Xiaoling 11.2 112
113 [[image:image-20220530090939-14.png]]
Xiaoling 1.2 114 )))
115
116 Use MQTT.fx to subscribe the topic
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118
Xiaoling 13.4 119 [[image:image-20220530091358-18.png||height="549" width="1035"]]
Xiaoling 1.2 120
121 Use CoAP Exension to send a update to CoAP server
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123
Xiaoling 13.2 124 [[image:image-20220530091237-17.png]]
Xiaoling 1.2 125
126 MQTT.fx get the update of this topic on CoAP server
127
Xiaoling 11.4 128
Xiaoling 1.2 129 == 3.4 Test CoAP Downlink ==
130
Xiaoling 1.3 131 (((
Xiaoling 1.2 132 Try to use MQTT.fx to publish a message to the topic (topic0) in the server. CoAP extension will see this incomming message.
Xiaoling 1.3 133 )))