Gateway UDP Data Decode

Hello everyone, I need help I am receiving below data from my Rpi through my own gateway and I want to decode it, anyone knows how to decode below data? Thanks!

RECEIVED 203 bytes from /192.168.0.107 : 1700
.203We got Data: 2 0 3a 0 33 38 33 30 3a 0 28 0 7b 22 72 78 70 6b 22 3a 5b 7b 22 74 6d 73 74 22 3a 31 32 37 34 36 37 32 36 30 34 2c 22 63 68 61 6e
22 3a 30 2c 22 72 66 63 68 22 3a 31 2c 22 66 72 65 71 22 3a 38 36 38 2e 31 30 30 30 30 30 2c 22 73 74 61 74 22 3a 31 2c 22 6d 6f 64 75 22 3a 22 4c
4f 52 41 22 2c 22 64 61 74 72 22 3a 22 53 46 31 32 42 57 31 32 35 22 2c 22 63 6f 64 72 22 3a 22 34 2f 35 22 2c 22 6c 73 6e 72 22 3a 38 2e 30 2c 22
72 73 73 69 22 3a 2d 35 38 2c 22 73 69 7a 65 22 3a 32 31 2c 22 64 61 74 61 22 3a 22 67 43 6f 64 41 53 59 41 43 51 41 50 53 62 38 39 65 6c 55 47 36
6b 6a 75 7a 48 4b 74 22 7d 5d 7d = < : 3830: ( {“rxpk”:[{“tmst”:1274672604,“chan”:0,“rfch”:1,“freq”:868.100000,“stat”:1,“modu”:“LORA”,“datr”:“SF1
2BW125”,“codr”:“4/5”,“lsnr”:8.0,“rssi”:-58,“size”:21,“data”:“gCodASYACQAPSb89elUG6kjuzHKt”}]}

You will find the UDP protocol specification here: https://github.com/Lora-net/packet_forwarder/blob/master/PROTOCOL.TXT.

Thank you so much for the link @brocaar
After using this link I am getting below error in my Rpi, can you help, please.

TypeError: lora_packet.fromWire is not a function
at Object. (/home/pi/Naveed/LoraPD3/LoraTest/demo1.js:11:26)
at Module._compile (internal/modules/cjs/loader.js:1015:30)
at Object.Module._extensions…js (internal/modules/cjs/loader.js:1035:10)
at Module.load (internal/modules/cjs/loader.js:879:32)
at Function.Module._load (internal/modules/cjs/loader.js:724:14)
at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:60:12)
at internal/main/run_main_module.js:17:47