# NCRL_MQTT
[TOC]
## Server
- Follow https://www.vultr.com/docs/install-mosquitto-mqtt-broker-on-ubuntu-20-04-server/

- Make IP open for everyone

$ cd /etc/mosquitto
$ vim mosquitto.conf
# 修改完後，重起服務
$ sudo systemctl status mosquitto


## Client

### Client OS ubuntu 20.04
- Follow https://github.com/ika-rwth-aachen/mqtt_client
### Client OS not ubuntu 20.04
#### 1. Prerequisites
- install docker ([reference](https://blog.gtwang.org/virtualization/ubuntu-linux-install-docker-tutorial/))

For Linux  : $ sudo apt-get install docker.io
For Rpi    : $ curl -fsSL https://get.docker.com/ | sh
# 打完下面這行要logout
$ sudo usermod -aG docker ${使用者名稱}

- download ncrl_mqtt repo

$ cd
# download repo for docker usage
$ git clone https://github.com/leeandy0822/ncrl_mqtt.git
$ cd ncrl_mqtt
# run docker
$ source docker_run.sh
#catkin_make and load env parameters
$ source env.sh


#### 2. 更改 broker host IP

$ roscd mqtt_client
$ cd launch
$ vim params.yaml


#### 3. Enable the mqtt_ros service

$ roslaunch mqtt_client standalone.launch


#### 4. Check the ros topics

| ROS Input | MQTT | ROS_Output |
| -------- | -------- | -------- |
| /ping/ros | /pingpong/ros | /pong/ros |
| /ping/primitive | /pingpong/primitive |/pong/primitive |


## Authorization

#### 1. broker 端新增 password file
- move to /etc/mosquito

$ cd /etc/mosquito
# 新增一個 password file
$ sudo mosquitto_passwd -c <password file name> <name>
# example
$ sudo mosquitto_passwd -c password ncqq
# 打密碼和確認密碼（這裡設定ee405423）
$ vim password
# username:log


#### 2. 重啟 broker 端 server

$ sudo service mosquitto restart

#### 3. 所有 client 都要新增 password 設定
- 開啟 mqtt_client/launch/params.yaml

$ cd ws/src/mqtt_client/launch
$ vim params.yaml 
# 在 broker 下面新增 user: 和 pass:
# 帳號密碼要與上面password file 一致