API¶
This document describes the PiKVM API. Since the system consists of microservices, here is a common API with a common entry point provided by Nginx. The examples above use curl and websocat with the -k option to disable SSL certificate verification, since the self-signed certificateis used in the default installation.
There is a third-party library for using the PiKVM API. Please note that this is an unofficial library, so use it carefully.
Authentication¶
All APIs are restricted to authentication. To make requests, you either need to auth each request individually, or get a token and pass it as a cookie with each request.
With enabled 2FA, you will need to add the one-time code to the password without spaces.
That is, if the password is foobar and the code is 123456, then you need to use foobar123456 as the password.
The code can be generated using any TOTP library, for example in Python:
import requests
import pyotp
user = "admin"
passwd = "admin"
secret = "3OBBOGSJRYRBZH35PGXURM4CMWTH3WSU" # Can be found in /etc/kvmd/totp.secret
print(requests.get(
url="https://pikvm/api/info",
verify=False, # For self-signed SSL certificate
headers={
"X-KVMD-User": user,
"X-KVMD-Passwd": passwd + pyotp.TOTP(secret).now(),
},
).text)
Since in the borderline case of the 2FA code lifetime, the code may be invalid, it makes sense to either handle error 403 by repeating the request in seconds.
A more correct way is to combine this method and check the remaining lifetime and postpone the request if there is a second or so left. You can find out how much time is left in this way:
totp = pyotp.TOTP(secret)
now = int(time.time())
remaining = now - (now % totp.interval)
Single request auth¶
There are two options here:
-
Using X-headers. Just pass
X-KVMD-UserandX-KVMD-Passwdwith the request:$ curl -k -H X-KVMD-User:admin -H X-KVMD-Passwd:admin https://<pikvm-ip>/api/auth/check -
Using HTTP Basic Auth. Please note: contrary to the standard, this method DOES NOT use the
WWW-Authenticateheader. HTTP Basic Auth in this implementation is intended only for compatibility with other systems, such as Prometheus.$ curl -k -u admin:admin https://<pikvm-ip>/api/auth/check
Session-based cookie auth¶
-
Get the access token for the user using
POST /api/auth/login:$ curl -k -v -X POST --data user=admin --data passwd=admin https://pikvm/api/auth/login ... < Set-Cookie: auth_token=796cb83b11de4fcb749bc1bad14a91fb06dede84672b2f847fef1e988e6900de; Path=/ ...On success the cookie
auth_tokenwill be received with200 OK. On invalid user or password you will get403 Forbidden. -
The handle
GET /api/auth/checkcan be used for check the auth status. Return of200 OKwill signal that user is authenticated. If the token or any of the single-request auth methods are missing,401 Unauthorizedwill be returned. In case of incorrect credentials or token,403 Forbiddenwill be returned. -
The handle
POST /api/auth/logoutcan be used to invalidate session token. The response codes will be similar to the previous handle.
WebSocket events¶
Most of the data during the user's work with pikvm is transmitted over WebSocket. This includes mouse events, keyboard input, change the state of the various subsystems (such as ATX and Mass Storage Drive). Each event type will be described in the corresponding paragraph for its component. When connecting via WebSocket, the client receives current states as separate events. Then, as the states change, it will receive new events.
In a normal situation, opening a socket session triggers the video streamer to start. The streamer works as long as there is at least one client connected via WebSocket. After the last connection is closed and the client timeout expires, the streamer will also be terminated.
It is possible create a session that will not start the streamer and will not be counted when counting clients to stop the streamer. To do this, use the URL parameter stream=0:
$ websocat -k wss://<pikvm-ip>/api/ws?stream=0 -H X-KVMD-User:admin -H X-KVMD-Passwd:admin
Output with initial events
{"event_type": "gpio_model_state", "event": {"scheme": {"inputs": {"led1": {"hw": {"driver": "__gpio__", "pin": 19}}, "led2": {"hw": {"driver": "__gpio__", "pin": 16}}}, "outputs": {"button1": {"switch": false, "pulse": {"delay": 0.1, "min_delay": 0.1, "max_delay": 0.1}, "hw": {"driver": "__gpio__", "pin": 26}}, "button2": {"switch": false, "pulse": {"delay": 0.1, "min_delay": 0.1, "max_delay": 0.1}, "hw": {"driver": "__gpio__", "pin": 20}}, "relay1": {"switch": true, "pulse": {"delay": 0.1, "min_delay": 0.1, "max_delay": 0.1}, "hw": {"driver": "relay", "pin": 0}}, "relay2": {"switch": true, "pulse": {"delay": 2.0, "min_delay": 0.1, "max_delay": 5.0}, "hw": {"driver": "relay", "pin": 1}}}}, "view": {"header": {"title": "Switches"}, "table": [[{"type": "label", "text": "Generic GPIO leds"}], null, [{"type": "label", "text": "Test 1:"}, {"type": "input", "channel": "led1", "color": "green"}, {"type": "output", "channel": "button1", "text": "Click"}], [{"type": "label", "text": "Test 2:"}, {"type": "input", "channel": "led2", "color": "green"}, {"type": "output", "channel": "button2", "text": "Click"}], null, [{"type": "label", "text": "HID Relays /dev/hidraw0"}], null, [{"type": "label", "text": "Relay #1:"}, {"type": "output", "channel": "relay1", "text": "Boop 0.1"}], [{"type": "label", "text": "Relay #2:"}, {"type": "output", "channel": "relay2", "text": "Boop 2.0"}]]}}}
{"event_type": "info_extras_state", "event": {"vnc": {"name": "VNC", "description": "Show VNC information", "icon": "share/svg/vnc.svg", "path": "vnc", "keyboard_cap": false, "daemon": "kvmd-vnc", "port": 5900, "place": 20, "enabled": true}, "ipmi": {"name": "IPMI", "description": "Show IPMI information", "icon": "share/svg/ipmi.svg", "path": "ipmi", "keyboard_cap": false, "daemon": "kvmd-ipmi", "port": 623, "place": 21, "enabled": true}}}
{"event_type": "info_hw_state", "event": {"platform": {"type": "rpi", "base": "Virtual Raspberry Pi"}, "health": {"temp": {"cpu": 36.511, "gpu": 35.0}, "throttling": {"raw_flags": 0, "parsed_flags": {"undervoltage": {"now": false, "past": false}, "freq_capped": {"now": false, "past": false}, "throttled": {"now": false, "past": false}}}}}}
{"event_type": "info_meta_state", "event": {"server": {"host": "localhost.localdomain"}, "kvm": {}}}
{"event_type": "info_system_state", "event": {"kvmd": {"version": "1.102"}, "streamer": {"app": "ustreamer", "version": "1.25", "features": {"WITH_OMX": false, "WITH_GPIO": false, "WITH_PTHREAD_NP": true, "WITH_SETPROCTITLE": true, "HAS_PDEATHSIG": true}}, "kernel": {"system": "Linux", "release": "5.8.10-arch1-1", "version": "#1 SMP PREEMPT Thu, 17 Sep 2020 18:01:06 +0000", "machine": "x86_64"}}}
{"event_type": "wol_state", "event": {"enabled": false, "target": {"ip": "255.255.255.255", "port": 9, "mac": ""}}}
{"event_type": "gpio_state", "event": {"inputs": {"led1": {"online": true, "state": false}, "led2": {"online": true, "state": false}}, "outputs": {"button1": {"online": true, "state": false, "busy": false}, "button2": {"online": true, "state": false, "busy": false}, "relay1": {"online": false, "state": false, "busy": false}, "relay2": {"online": false, "state": false, "busy": false}}}}
{"event_type": "hid_state", "event": {"online": true, "keyboard": {"online": true, "leds": {"caps": false, "scroll": false, "num": false}}, "mouse": {"online": true}}}
{"event_type": "atx_state", "event": {"enabled": true, "busy": false, "leds": {"power": false, "hdd": false}}}
{"event_type": "msd_state", "event": {"enabled": true, "online": true, "busy": false, "storage": {"size": 234950152192, "free": 23514271744, "images": {}, "uploading": false}, "drive": {"image": null, "connected": false, "cdrom": true}, "features": {"multi": true, "cdrom": true}}}
{"event_type": "streamer_state", "event": {"limits": {"max_fps": 40}, "params": {"desired_fps": 30, "quality": 80}, "snapshot": {"saved": null}, "streamer": null, "features": {"quality": true, "resolution": false}}}
{"event_type": "loop", "event": {}}
After connecting the client receives a bundle of states of all KVMD subsystems. After the batch is completed, it sends a loop event, which means that the websocket has entered event loop mode. Now it will send new states and respond to client's requests.
Another type of event is ping, which can be sent by the client: {"event_type": "ping", "event": {}}. If the server is running, it will respond with pong: {"event_type": "pong", "event": {}}.
Sending key events using Python
For keypresses, set event_type to key and fill in the event structure with key and state, where key is the key from mapping and state is boolean that determines if the key is pressed or released:
# python, install websocket-client
import websocket
import ssl, time
uri = "wss://10.0.0.7/api/ws?stream=0"
headers = {"X-KVMD-User": "admin", "X-KVMD-Passwd": "admin"}
ws = websocket.WebSocket(sslopt={"cert_reqs": ssl.CERT_NONE})
ws.connect(uri, header=headers)
ws.send('{"event_type": "key", "event": {"key": "Enter", "state": true}}')
time.sleep(0.05)
ws.send('{"event_type": "key", "event": {"key": "Enter", "state": false}}')
ws.close()
System functions¶
Get system info¶
The GET /api/info handle returns the general information about the PiKVM device.
Parameters:
fields=...(optional) - Only specified categories will be returned, for examplefields=system,hw. By default all categories will be displayed.
$ curl -k -u admin:admin https://<pikvm-ip>/api/info
Click to expand
{
"ok": true,
"result": {
"extras": { // Installed applications; null on internal error
"ipmi": {
"daemon": "kvmd-ipmi",
"description": "Show IPMI information",
"enabled": true,
"icon": "share/svg/ipmi.svg",
"keyboard_cap": false,
"name": "IPMI",
"path": "ipmi",
"place": 21,
"port": 623
},
"vnc": {
"daemon": "kvmd-vnc",
"description": "Show VNC information",
"enabled": true,
"icon": "share/svg/vnc.svg",
"keyboard_cap": false,
"name": "VNC",
"path": "vnc",
"place": 20,
"port": 5900
}
},
"hw": { // Hardware info
"health": {
"temp": {
"cpu": 36.511, // /sys/class/thermal/thermal_zone0/temp / 1000; null on error
"gpu": 35.0 // vcgencmd measure_temp; null on error
},
"throttling": { // vcgencmd get_throttled; null on error
"parsed_flags": {
"freq_capped": {
"now": false,
"past": false
},
"throttled": {
"now": false,
"past": false
},
"undervoltage": {
"now": false,
"past": false
}
},
"raw_flags": 0
}
},
"platform": {
"base": "Raspberry Pi 4 Model B Rev 1.1", // /proc/device-tree/model; null on error
"serial": "0000000000000000", // /proc/device-tree/serial-number; null on error
"type": "rpi"
}
},
"meta": { // /etc/kvmd/meta.yaml; null on error
"kvm": {},
"server": {
"host": "localhost.localdomain"
}
},
"system": {
"kernel": {
"machine": "x86_64",
"release": "5.8.14-arch1-1",
"system": "Linux",
"version": "#1 SMP PREEMPT Wed, 07 Oct 2020 23:59:46 +0000"
},
"kvmd": {
"version": "2.1"
},
"streamer": {
"app": "ustreamer",
"features": { // {} on error
"HAS_PDEATHSIG": true,
"WITH_GPIO": false,
"WITH_OMX": false,
"WITH_PTHREAD_NP": true,
"WITH_SETPROCTITLE": true
},
"version": "2.1" // "" on error
}
}
}
}
Each category is represented by its own event in the websocket (info_hw_state, info_system_state, etc). The event content has the same format as the category content in API.
Get system log¶
The GET /api/log handle displays logs from all KVMD services as plain text.
Parameters:
follow=1(optional) - Turns the request into long-polling mode and follow log messages in real time.seek=N(optional) - Runs the log for the specified time in seconds, for exampleseek=3600will show the log for the last hour.
$ curl -k -u admin:admin https://<pikvm-ip>/api/log
ATX power management¶
Get ATX state¶
The GET /api/atx handle shows the current ATX state.
$ curl -k -u admin:admin https://<pikvm-ip>/api/atx
Click to expand
{
"ok": true,
"result": {
"busy": false, // True if ATX is busy performing an operation and does not accept commands
"enabled": true,
"leds": {
"hdd": false,
"power": false
}
}
}
Set ATX power¶
The POST /api/atx/power handle changes ATX power state to desired.
Parameters:
action=...- Describes desired state:on- Turn on (do nothing in case PSU is already on).off- Turn off (aka soft-off), emulates click on the power button.off_hard- Perform long press on the power button (5+ seconds).reset_hard- Emulates pressing reset button (hardware hot reset).
wait=1(optional) - Says if call should return immediately or just after finishing operation.
$ curl -X POST -k -u admin:admin https://<pikvm-ip>/api/atx/power?action=on
Click ATX button¶
The POST /api/atx/click handle sends the ATX button press event.
Parameters:
button=...- Specifies the desired PC case button:power- Short click on the power button.power_long- Long press on the power button (5+ seconds).reset- Short click on the reset button.
wait=1(Optional) - Says if call should return immediately or just after finishing operation.
$ curl -X POST -k -u admin:admin https://<pikvm-ip>/api/atx/click?button=power
Mass Storage Drive¶
Get MSD state¶
The GET /api/msd handle shows the current MSD state.
$ curl -k -u admin:admin https://<pikvm-ip>/api/msd
Upload MSD image¶
The POST /api/msd/write uploads an image to MSD.
Parameters:
image=...- Specifies the name of the image.- Binary data should be passed to the POST body.
$ # create a test image
$ dd if=/dev/zero of=test.iso bs=1M count=1
$ # upload it to pikvm
$ curl -v -X POST --data-binary @test.iso -k -u admin:admin https://<pikvm-ip>/api/msd/write?image=test.iso
Upload MSD image by URL¶
The POST /api/msd/write_remote handle downloads an image from HTTP(S) URL to the MSD.
Parameters:
url=...- Image URL.image=...(optional) - Image name.timeout=N(optional) - Remote request timeout, 10 seconds by default.
Note
This is a long-polling request. Do not interrupt the request until the download is complete, otherwise the download will stop.
$ # create test image
$ dd if=/dev/zero of=test.iso bs=1M count=1
$ # upload it to pikvm
$ curl -v -X POST -k -u admin:admin https://<pikvm-ip>/api/msd/write_remote?url=http://example.com/test.iso
Set MSD parameters¶
The POST /api/msd/set_params handle changes the current image and/or set drive parameters
Parameters:
image=...(optional) - Change the current image.cdrom=1|0(optional) - Change the media type to the CD-ROM on1, otherwise to the Flash.
$ curl -X POST -k -u admin:admin "https://<pikvm-ip>/api/msd/set_params?image=test.iso&cdrom=1"
Control MSD¶
The POST /api/msd/set_connected connects or disconnect the MSD to the host.
Parameters:
connected=1|0- Change the state.
$ curl -X POST -k -u admin:admin https://<pikvm-ip>/api/msd/set_connected?connected=1
Remove MSD image¶
The POST /api/msd/remove handle removes the specified image.
Parameters:
image=...- The image name.
$ curl -X POST -k -u admin:admin https://<pikvm-ip>/api/msd/remove?image=test.iso
Reset MSD¶
The POST /api/msd/reset handle resets the drive.
$ curl -X POST -k -u admin:admin https://<pikvm-ip>/api/msd/reset
GPIO¶
Get GPIO state¶
The GET /api/gpio handle shows the current GPIO state.
$ curl -k -u admin:admin https://<pikvm-ip>/api/gpio
Switch GPIO channel¶
The POST /api/gpio/switch handle interacts with selected GPIO driver channel in switch mode.
Parameters:
channel=...- The GPIO driver channel.state=1|0- The new switch state.wait=1(optional) - Says if call should return immediately or just after finishing operation.
Pulse GPIO channel¶
The POST /api/gpio/pulse handle interacts with selected GPIO driver channel in pulse mode.
Parameters:
channel=...- The GPIO driver channel.delay=N.N(optional) - The pulse time in seconds (float),0for default delay.wait=1(optional) - Says if call should return immediately or just after finishing operation.
Misc¶
Get Prometheus metrics¶
The GET /api/export/prometheus/metrics handle returns the Prometheus metrics. Also see here for details.
$ curl -k -u admin:admin https://<pikvm-ip>/api/export/prometheus/metrics
To be continued ===>¶
You can find all existing APIs in the KVMD source tree. We would appreciate your help with documentation.