105 lines
2.3 KiB
Markdown
105 lines
2.3 KiB
Markdown
|
QMP
|
||
|
|
===
|
||
|
|
|
||
|
|
Package `qmp` enables interaction with QEMU instances via the QEMU Machine Protocol (QMP).
|
||
|
|
|
||
|
|
## Available Drivers
|
||
|
|
|
||
|
|
### Libvirt
|
||
|
|
|
||
|
|
If your environment is managed by Libvirt, QMP interaction must be proxied through the Libvirt daemon. This can be be done through two available drivers:
|
||
|
|
|
||
|
|
#### RPC
|
||
|
|
|
||
|
|
The RPC driver provides a pure Go implementation of Libvirt's RPC protocol.
|
||
|
|
|
||
|
|
```go
|
||
|
|
//conn, err := net.DialTimeout("unix", "/var/run/libvirt/libvirt-sock", 2*time.Second)
|
||
|
|
conn, err := net.DialTimeout("tcp", "192.168.1.1:16509", 2*time.Second)
|
||
|
|
monitor := libvirtrpc.New("stage-lb-1", conn)
|
||
|
|
```
|
||
|
|
|
||
|
|
#### virsh
|
||
|
|
|
||
|
|
A connection to the monitor socket is provided by proxing requests through the `virsh` executable.
|
||
|
|
|
||
|
|
```go
|
||
|
|
monitor, err := qmp.NewLibvirtMonitor("qemu:///system", "stage-lb-1")
|
||
|
|
```
|
||
|
|
|
||
|
|
### Socket
|
||
|
|
|
||
|
|
If your QEMU instances are not managed by libvirt, direct communication over its UNIX socket is available.
|
||
|
|
|
||
|
|
```go
|
||
|
|
monitor, err := qmp.NewSocketMonitor("unix", "/var/lib/qemu/example.monitor", 2*time.Second)
|
||
|
|
```
|
||
|
|
|
||
|
|
## Examples
|
||
|
|
|
||
|
|
Using the above to establish a new `qmp.Monitor`, the following examples provide a brief overview of QMP usage.
|
||
|
|
|
||
|
|
_error checking omitted for the sake of brevity._
|
||
|
|
|
||
|
|
### Command Execution
|
||
|
|
```go
|
||
|
|
type StatusResult struct {
|
||
|
|
ID string `json:"id"`
|
||
|
|
Return struct {
|
||
|
|
Running bool `json:"running"`
|
||
|
|
Singlestep bool `json:"singlestep"`
|
||
|
|
Status string `json:"status"`
|
||
|
|
} `json:"return"`
|
||
|
|
}
|
||
|
|
|
||
|
|
monitor.Connect()
|
||
|
|
defer monitor.Disconnect()
|
||
|
|
|
||
|
|
cmd := []byte(`{ "execute": "query-status" }`)
|
||
|
|
raw, _ := monitor.Run(cmd)
|
||
|
|
|
||
|
|
var result StatusResult
|
||
|
|
json.Unmarshal(raw, &result)
|
||
|
|
|
||
|
|
fmt.Println(result.Return.Status)
|
||
|
|
```
|
||
|
|
|
||
|
|
```
|
||
|
|
running
|
||
|
|
```
|
||
|
|
|
||
|
|
### Event Monitor
|
||
|
|
|
||
|
|
```go
|
||
|
|
monitor.Connect()
|
||
|
|
defer monitor.Disconnect()
|
||
|
|
|
||
|
|
stream, _ := monitor.Events()
|
||
|
|
for e := range stream {
|
||
|
|
log.Printf("EVENT: %s", e.Event)
|
||
|
|
}
|
||
|
|
|
||
|
|
```
|
||
|
|
|
||
|
|
```
|
||
|
|
$ virsh reboot example
|
||
|
|
Domain example is being rebooted
|
||
|
|
```
|
||
|
|
|
||
|
|
```
|
||
|
|
EVENT: POWERDOWN
|
||
|
|
EVENT: SHUTDOWN
|
||
|
|
EVENT: STOP
|
||
|
|
EVENT: RESET
|
||
|
|
EVENT: RESUME
|
||
|
|
EVENT: RESET
|
||
|
|
...
|
||
|
|
```
|
||
|
|
|
||
|
|
## More information
|
||
|
|
|
||
|
|
* [QEMU QMP Wiki](http://wiki.qemu.org/QMP)
|
||
|
|
* [QEMU QMP Intro](http://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/qmp-intro.txt;hb=HEAD)
|
||
|
|
* [QEMU QMP Events](http://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/qmp-events.txt;hb=HEAD)
|
||
|
|
* [QEMU QMP Spec](http://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/qmp-spec.txt;hb=HEAD)
|