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Wiki source code of Set up CoAP Server

Version 16.2 by Xiaoling on 2022/07/22 16:43
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1 **~ Contents:**
2
3 {{toc/}}
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5
6
7 = 1. Introduction =
8
9 (((
10 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.
11 )))
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14 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.
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17 [[image:image-20220530084843-1.png]]
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19 Network structure
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21
22 = 2. Install CoAP server =
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24 Set up example in Ubuntu 18.04
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26 (% class="box" %)
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28 sudo apt-get update
29 sudo apt-get upgrade
30 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.
31 sudo dpkg –i emqx-ubuntu18.04-v3.2.4_amd64.deb  #install EMQX
32 emqx start            # Start EMQX service
33 emqx_ctl status   #check if EMQX is running
34 ./bin/emqx_ctl plugins load emqx_coap # Run COAP service
35 )))
36
37 (((
38 (% 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.**
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40
41 )))
42
43 = 3. Test CoAP Server =
44
45 == 3.1 Install Copper in Chrome ==
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47 (((
48 ~1. Download Copper4Cr from [[https:~~/~~/github.com/mkovatsc/Copper4Cr>>url:https://github.com/mkovatsc/Copper4Cr]] and unpack it.
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50
51 (((
52 2. Run install.bat in the directory.
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54 [[image:image-20220530085327-2.png]]
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56
57 Run install.bat
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59
60 3. Load the unpacked CoAP APP in Google Chrome:
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62 [[image:image-20220530085423-3.png||height="241" width="1250"]]
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64 Install Copper APP
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67 [[image:image-20220530085531-4.png]]
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69 Install APP Successful
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72 4. Load the unpacked CoAP extension in Google Chrome:
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74 [[image:image-20220530085638-5.png||height="338" width="1320"]]
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76 Install Copper Extension
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78
79 [[image:image-20220530090104-7.png||height="389" width="1282"]]
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81 Install Extension Successful
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83
84 5. Replace the appID in file extension\endpoint\ClientPortChrome.js to Copper (Cu4Cr) Application ID
85
86 [[image:image-20220530090444-10.png]]
87
88 Replace ID
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91 6. Open the Copper extension. If you see below message, means install successfully.
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93 [[image:image-20220530090404-9.png||height="658" width="1238"]]
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95 Install Finished
96
97
98 == 3.2 Test CoAP connection ==
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100 (((
101 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.
102
103 [[image:image-20220530090848-13.png||height="616" width="1154"]]
104 )))
105
106 Connect to CoAP server
107
108
109 == 3.3 Test CoAP Uplink ==
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111 (((
112 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.
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114 [[image:image-20220530090939-14.png]]
115 )))
116
117 Use MQTT.fx to subscribe the topic
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119
120 [[image:image-20220530091358-18.png||height="549" width="1035"]]
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122 Use CoAP Exension to send a update to CoAP server
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124
125 [[image:image-20220530091237-17.png]]
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127 MQTT.fx get the update of this topic on CoAP server
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129
130 == 3.4 Test CoAP Downlink ==
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132 (((
133 Try to use MQTT.fx to publish a message to the topic (topic0) in the server. CoAP extension will see this incomming message.
134 )))