Note:
This project has been moved to: https://github.com/mkrainbow/
The new RTIO project URL is: https://github.com/mkrainbow/rtio
The new RTIO API is more concise, such as registering handler functions for URIs without needing to calculate the hash first. It also adds new features, such as support for TLS and JWT authentication. Additionally, the new version does not follow the naming conventions of the current version.
The device SDK has been updated to include a C SDK, which can run on constrained devices. The GO SDK has also been updated.
Thank you for following this project!注意：
该项目已迁移至：https://github.com/mkrainbow/
新版RTIO地址为：https://github.com/mkrainbow/rtio
新版RTIO API更为简洁，比如给URI注册处理函数，无需先计算哈希值；同时增加了新特性，比如支持TLS和JWT验证。另外，新版本没有延续当前版面的命名方式。
设备SDK，增加了C SDK，可运行于受限设备。更新了GO SDK。
感谢您的关注！
RTIO提供设备上云的端到端解决方案，主要包括设备接入、设备代理、后端服务代理等功能：
- 用户端使用HTTP GET、POST方法通过RTIO控制和实时观察设备（通常用户端下发指令、观察设备状态）
- 设备通过GET、POST接口访问RTIO代理的资源（通常设备端获取服务端资源、上报事件）
- 用户可访问NAT网络后的设备
native │ could
│ ┌───────┐ ┌──────────┐
┌──────────┐ tcp/tls │ │ ├─────► device │
│ device ├───────────┼─────► │ │ verifier │
└──────────┘ │ │ │ └──────────┘
│ │ RTIO │
┌──────────┐ http/https│ │ │ ┌──────────┐
│ user ├───────────┼─────► │ │ device │
└──────────┘ │ │ ├─────► services │
phone/web/pc... │ └───────┘ └──────────┘
- REST-Like模型，其参考RESTFul模型
- 用户端通过HTTP访问设备，无需集成SDK
- 用户端通过HTTP即可实时观察设备（非轮询）
- 解耦资源实现和资源调用者（以URI标识不同资源或能力，无topic耦合）
- 单节点支持百万连接（压测报告）
RTIO简化设备接入云端开发。设备也是服务资源的提供者，RTIO采取REST-Like模型，使设备端开发具有和WEB服务开发相似的体验和高效。主要有以下优势：
- 以URI标识不同资源或能力，比如设备提供V2/V3接口，方便设备资源或能力迭代
- 通过GET、POST和ObGet（Observe-GET）等方法交互，流程更简单（相比MQTT减少一半以上交互，可参考FQA部分）
- 解耦资源实现和资源调用者，可使用工具独立测试（类似使用curl/postman工具验证WEB服务接口）
REST-Like模型，这里指类似REST模型，但不以HTTP协议作为底层协议，模型提供了GET和POST方法和ObGET（Observe-GET，观察者模式）等方法。
RTIO交互示例可参考下文RTIO和MQTT服务交互比较。
环境需要安装golang（1.20版本以上）和make工具。
git clone https://github.com/guowenhe/rtio.git
cd rtio
make成功编译后，out目录下会生成执行文件，主要文件如下，rtio为服务端，printer为设备端。
$ tree out/
out/
├── examples
│ ├── printer
│
├── rtio
运行示例，启动rtio服务（可通过-h参数查看帮助）。
$ ./out/rtio -disable.deviceverify -disable.deviceservice -log.level=info
INF cmd/rtio/rtio.go:77 > rtio starting ...另一终端启动设备，模拟打印机。
$ ./out/examples/printer
INF internal/deviceaccess/access_client/devicesession/devicesession.go:675 > serving 另一终端模拟用户端，下达开始打印指令。
$ curl -X POST "http://127.0.0.1:17317/cfa09baa-4913-4ad7-a936-2e26f9671b04/post_handler" -d '{"uri":"/printer/action","id":12667,"data":"c3RhcnQ="}'
{"id":12667,"code":"CODE_OK","data":"cHJpbnQgc3RhcnRlZA=="} # 模拟用户端，持续获取打印进度。
$ curl -X GET "http://127.0.0.1:17317/cfa09baa-4913-4ad7-a936-2e26f9671b04/obget_handler?uri=%2Fprinter%2Fstatus&id=12334&data=MTIzNDU%3D"
{"result":{"id":12334,"fid":0,"code":"CODE_CONTINUE","data":"cHJpbnRpbmcgNDUl"}}
{"result":{"id":12334,"fid":1,"code":"CODE_CONTINUE","data":"cHJpbnRpbmcgNDgl"}}
{"result":{"id":12334,"fid":2,"code":"CODE_CONTINUE","data":"cHJpbnRpbmcgNTIl"}}
...
{"result":{"id":12334,"fid":18,"code":"CODE_CONTINUE","data":"cHJpbnRpbmcgOTEl"}} # data部分base64解码后：printing 91%
{"result":{"id":12334,"fid":19,"code":"CODE_CONTINUE","data":"cHJpbnRpbmcgOTQl"}}
{"result":{"id":12334,"fid":20,"code":"CODE_CONTINUE","data":"cHJpbnRpbmcgOTgl"}}
{"result":{"id":12334,"fid":21,"code":"CODE_CONTINUE","data":"cHJpbnRpbmcgMTAwJQ=="}} # data部分base64解码后：printing 100%
{"result":{"id":12334,"fid":22,"code":"CODE_TERMINATE","data":""}}设备端代码，handler实现：
func handlerAction(req []byte) ([]byte, error) {
log.Info().Str("req", string(req)).Msg("")
return []byte("print started"), nil
}
func handerStatus(ctx context.Context, req []byte) (<-chan []byte, error) {
log.Info().Str("req", string(req)).Msg("")
respChan := make(chan []byte, 1)
go func(context.Context, <-chan []byte) {
for {
select {
...
case <-t.C:
respChan <- []byte("printing " + strconv.Itoa(progress) + "%")
}
}(ctx, respChan)
return respChan, nil
}
}设备端代码，给URI注册handler：
session := ds.NewDeviceSession(conn, deviceID, deviceSecret)
...
// URI: /printer/action 0x44d87c69
session.RegisterPostHandler(0x44d87c69, handlerAction)
// URI: /printer/status 0x781495e7
session.RegisterObGetHandler(0x781495e7, handerStatus)备注：
- 设备集成具体步骤参见设备SDK。
- GET/POST每次交互都带有URI标识，为压缩URI数据量，设备和RTIO服务交互过程采用4字节的哈希摘要（CRC32）通信，可使用rtio-urihash工具计算。
- 用户端Javascript可参考：user.html。
- rtio-device-sdk-go 支持Golang
目前完成设备端到服务端接入和Demo示例，rtio核心部分：
- HTTP远程调用设备端资源（Get、Post、ObGet）
- 设备端调用后端服务资源（Get、Post）
-
RTIO和MQTT服务有何不同？
他们都能与NAT后面的设备通信，MQTT为发布订阅模型，是多对多的模型，RTIO是点对点模型。
点对点通信场景中，MQTT通常需要定义一对topic（*_req和*_resp）来实现请求和响应，而这对topic相关的处理函数（Handler）耦合在两个系统中。RTIO通过URI标识不同资源或能力，解耦资源实现和资源调用者。
-
什么场景选择点对点通信？U2M（User To Machine）选择哪种模型更合适？
“点对点通信”为两台设备间通信，“多对多通信”即多台设备间通行。“多对多”通信有多种实现模型，这里主要对比MQTT的“发布订阅”模型。
U2M为用户端（比如手机）设备控制IoT设备，是典型的点对点通信。如果采用发布订阅作为通信模型，也可实现对IoT设备控制。但相比点对点通信会复杂许多，可参考下文“RTIO和MQTT服务交互比较”。
另外，一个用户控制多台IoT设备，点对点通信是否适用？如果IoT设备间不进行复杂的交互（比如10台打印机之间没交互），这里用户相当于批量的对打印机控制，仅增加批量的控制逻辑（比如循环对10台打印机处理）即可，该场景点对点模型仍比发布订阅模型交互简单。
-
RTIO名字含义？
RTIO - Real Time Input Output。“实时输入输出”，这里的“实时”指在期望的时间完成通信，否则返回超时错误。通过同步通信方式使IoT（特别是远程控制IoT设备）开发更简单。
-
RTIO和MQTT服务交互比较，请求到云端获取version列表
LoadingsequenceDiagram Title: get versions over mqtt participant device as mqtt-device participant broker as mqtt-broker participant app as app-server app ->> broker: SUBSCRIBE toppic: $diviceid_get_versins_req broker -->> app: SUBACK device ->> broker: SUBSCRIBE toppic: $diviceid_get_versins_resp broker -->> device: SUBACK device ->> broker: PUBLISH toppic: $diviceid_get_versins_req broker -->> device: PUBACK broker ->> app: PUBLISH toppic: $diviceid_get_versins_req app -->> broker: PUBACK app ->> app: query versions app ->> broker: PUBLISH toppic: $diviceid_get_versins_resp broker -->> app: PUBACK broker ->> device: PUBLISH toppic: $diviceid_get_versins_resp device -->> broker: PUBACKLoadingsequenceDiagram Title: get versions over rtio participant device as rtio-device participant rtio as rtio-server participant app as app-server(resource-server) rtio ->> rtio: auto discover resource and registry device ->> rtio: GET /resource/versins rtio ->> app: GET app -->> rtio: versions rtio -->> device: versions -
用户控制设备开关
LoadingsequenceDiagram Title: power on over mqtt participant device as mqtt-device participant broker as mqtt-broker participant app as app app ->> broker: SUBSCRIBE toppic: $diviceid_led_power_resp broker -->> app: SUBACK device ->> broker: SUBSCRIBE toppic: $diviceid_led_power_req broker -->> device: SUBACK app ->> app: user power on app ->> broker: PUBLISH toppic: $diviceid_led_power_req broker -->> app: PUBACK note over app,broker : means brocker successfully received not device broker ->> device: PUBLISH toppic: $diviceid_led_power_req device -->> broker: PUBACK device ->> device: led power action device ->> broker: PUBLISH toppic: $diviceid_led_power_resp broker -->> device: PUBACK broker ->> app: PUBLISH toppic: $diviceid_led_power_resp app -->> broker: PUBACKLoadingsequenceDiagram Title: power on over rtio participant device as rtio-device participant rtio as rtio-server participant app as app app ->> app: user power on app ->> rtio: POST $device_name/led_power note right of app : could set timeout rtio ->> device: POST /led_power device ->> device: led power action device -->> rtio: led_power status rtio -->> app: led_power status -
观察者模式（MQTT服务没有此模式）
sequenceDiagram
Title: rtio observation
participant device as rtio-device
participant rtio as rtio-server
participant app as app
app ->> app: observe progress
app ->> rtio: OBGET $device_name/progress
rtio ->> device: OBGET /progress
device -->> rtio: 20%
rtio -->> app: 20%
device -->> rtio: 30%
rtio -->> app: 30%
note over app,device : The observation can be terminated by device or app
device -->> rtio: 100%
rtio -->> app: 100%