wmi_windows.go

package collectors

import (
	"fmt"

	ole "github.com/mattn/go-ole"
	"github.com/mattn/go-ole/oleutil"
)

func wmiQuery(query string) ([]map[string]string, error) {
	ole.CoInitialize(0)
	defer ole.CoUninitialize()

	unknown, err := oleutil.CreateObject("WbemScripting.SWbemLocator")
	if err != nil {
		return nil, err
	}
	defer unknown.Release()

	wmi, err := unknown.QueryInterface(ole.IID_IDispatch)
	if err != nil {
		return nil, err
	}
	defer wmi.Release()

	// service is a SWbemServices
	serviceRaw, err := oleutil.CallMethod(wmi, "ConnectServer")
	if err != nil {
		return nil, err
	}
	service := serviceRaw.ToIDispatch()
	defer service.Release()

	// result is a SWBemObjectSet
	resultRaw, err := oleutil.CallMethod(service, "ExecQuery", query)
	if err != nil {
		return nil, err
	}
	result := resultRaw.ToIDispatch()
	defer result.Release()

	count, err := oleInt64(result, "Count")
	if err != nil {
		return nil, err
	}

	var results []map[string]string
	for i := 0; i < count; i++ {
		// item is a SWbemObject, but really a Win32_Process
		itemRaw, err := oleutil.CallMethod(result, "ItemIndex", i)
		if err != nil {
			return nil, err
		}
		item := itemRaw.ToIDispatch()
		defer item.Release()

		props, err := oleutil.GetProperty(item, "Properties_")
		if err != nil {
			return nil, err
		}
		

		m := make(map[string]string)
		results = append(results, m)
		for _, p := range properties {
			asString, err := oleutil.GetProperty(item, p)
			if err != nil {
				return nil, err
			}
			m[p] = asString.ToString()
		}
	}
	return results, nil
}

func oleInt64(item *ole.IDispatch, prop string) (int64, error) {
	v, err := oleutil.GetProperty(item, prop)
	if err != nil {
		return 0, err
	}
	i := int64(v.Val)
	return i, nil
}

func oleProperties(object *ole.IDispatch) ([]OleProperty, error) {
	// SWbemPropertySet
	propsV, err := oleutil.GetProperty(object, "Properties_")
	if err != nil {
		return nil, err
	}
	props := propsV.ToIDispatch()
	defer props.Release()
	count, err := oleInt64(props, "Count)
	if err != nil {
		return nil, err
	}
	var r []string
	for i := 0; i < count; i++ {
		itemRaw, err := oleutil.CallMethod(props, "Item", i)
		if err != nil {
			return nil, err
		}
		item := itemRaw.ToIDispatch()
		defer item.Release()
	}
	return r, nil
}

type OleProperty struct {
	Name string

}

wmi_windows_test.go

package collectors

import (
	"fmt"
	"testing"
)

func TestWmiQuery(t *testing.T) {
	r, err := wmiQuery("SELECT Caption, CommittedBytes, AvailableBytes, PercentCommittedBytesInUse, PagesPerSec, PageFaultsPerSec FROM Win32_PerfFormattedData_PerfOS_Memory")
	if err != nil {
		t.Fatal(err)
	}
	for k, v := range r {
		fmt.Println(k, v)
	}
}