28 lines
633 B
Markdown
28 lines
633 B
Markdown
|
# MQTT in curl
|
||
|
|
|
||
|
|
## Usage
|
||
|
|
|
||
|
|
A plain "GET" subscribes to the topic and prints all published messages.
|
||
|
|
Doing a "POST" publishes the post data to the topic and exits.
|
||
|
|
|
||
|
|
Example subscribe:
|
||
|
|
|
||
|
|
curl mqtt://host.home/bedroom/temp
|
||
|
|
|
||
|
|
Example publish:
|
||
|
|
|
||
|
|
curl -d 75 mqtt://host.home/bedroom/dimmer
|
||
|
|
|
||
|
|
## What does curl deliver as a response to a subscribe
|
||
|
|
|
||
|
|
It outputs two bytes topic length (MSB | LSB), the topic followed by the
|
||
|
|
payload.
|
||
|
|
|
||
|
|
## Caveats
|
||
|
|
|
||
|
|
Remaining limitations:
|
||
|
|
- Only QoS level 0 is implemented for publish
|
||
|
|
- No way to set retain flag for publish
|
||
|
|
- No TLS (mqtts) support
|
||
|
|
- Naive EAGAIN handling will not handle split messages
|