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I am trying to save to my database, latitude and longitude values as the geography point datatype and i want to be able to retrieve the values accordingly. I have implemented the following
my model device.go looks like this
device.go
package models
import (
"bytes"
"database/sql/driver"
"encoding/binary"
"encoding/hex"
"fmt"
"time"
"gorm.io/gorm"
)
type GeoPoint struct {
Lat float64 `json:"lat"`
Lng float64 `json:"lng"`
}
func (p *GeoPoint) String() string {
return fmt.Sprintf("SRID=4326;POINT(%v %v)", p.Lng, p.Lat)
}
// Scan implements the sql.Scanner interface.
func (p *GeoPoint) Scan(val interface{}) error {
b, err := hex.DecodeString(string(val.(string)))
if err != nil {
return err
}
r := bytes.NewReader(b)
var wkbByteOrder uint8
if err := binary.Read(r, binary.LittleEndian, &wkbByteOrder); err != nil {
return err
}
var byteOrder binary.ByteOrder
switch wkbByteOrder {
case 0:
byteOrder = binary.BigEndian
case 1:
byteOrder = binary.LittleEndian
default:
return fmt.Errorf("invalid byte order %d", wkbByteOrder)
}
var wkbGeometryType uint32
if err := binary.Read(r, byteOrder, &wkbGeometryType); err != nil {
return err
}
if err := binary.Read(r, byteOrder, p); err != nil {
return err
}
return nil
}
// Value impl.
func (p GeoPoint) Value() (driver.Value, error) {
return p.String(), nil
}
type Device struct {
gorm.Model
Id int `json:"id" gorm:"primaryKey"`
UserId int `json:"user_id" gorm:"uniqueIndex"`
LatestLocation GeoPoint `json:"latest_location" gorm:"type:geography(POINT, 4326)"`
CreatedAt time.Time
UpdatedAt time.Time
}
I am able to save data to the database and this is how it looks like in the database
But when i want to retrieve the record with the latitude and longitude, I get wrong data records and i am not sure why.
this is my code
location.go
package apisLocation
import (
"fmt"
db "atm/pkg/configs/database"
models "atm/pkg/models"
"strconv"
"github.com/gofiber/fiber/v2"
)
func GetLocation(c *fiber.Ctx) error {
userId, err := strconv.Atoi(c.Params("userId"))
if err != nil {
return c.Status(400).JSON(err.Error())
}
if checkIfUserExists(userId) {
return c.Status(400).JSON(fiber.Map{"error": "User does not exist"})
}
var device models.Device
db.DB.Db.Find(&device, models.Device{UserId: userId})
return c.Status(200).JSON(fiber.Map{"location": device.LatestLocation})
}
func checkIfUserExists(userId int) bool {
var device models.Device
db.DB.Db.Find(&device, models.Device{UserId: userId})
return device.Id == 0
}
when i run the GetLocation method, the response i get is not accurate, i get a value of this
"location": {
"lat": 1.7689674224598998e+71,
"lng": -3.639753837714837e+173
},
which isn't the lat and long that is saved in the database.
I think somehow when it is being decoded, something changes but i am not sure how to fix this issue.
Any help is appreciated
I found a solution to your problem here https://github.com/go-pg/pg/issues/829#issuecomment-505882885
The problem in your code was just declaring your wkbGeometryType as uint32, not uint64.
Im having trouble looping through the Google Places API in Go.
Google's Places API returns 20 results max with a pagetoken parameter to add to the query to return the next 20 results until theres none left.
I currently am able to send a query request, return the json and output it in terminal, but when i try to loop back through and add the pagetoken parameter to the query, it runs but only returns the first page results again but with another page token. Any Idea what im doing wrong?
package main
import (
"bytes"
"encoding/json"
"fmt"
"io/ioutil"
"log"
"net/http"
"strconv"
// "os"
)
type GooglePlaces struct {
HTMLAttributions []interface{} `json:"html_attributions"`
NextPageToken string `json:"next_page_token"`
Results []struct {
Geometry struct {
Location struct {
Lat float64 `json:"lat"`
Lng float64 `json:"lng"`
} `json:"location"`
Viewport struct {
Northeast struct {
Lat float64 `json:"lat"`
Lng float64 `json:"lng"`
} `json:"northeast"`
Southwest struct {
Lat float64 `json:"lat"`
Lng float64 `json:"lng"`
} `json:"southwest"`
} `json:"viewport"`
} `json:"geometry"`
Icon string `json:"icon"`
ID string `json:"id"`
Name string `json:"name"`
OpeningHours struct {
OpenNow bool `json:"open_now"`
WeekdayText []interface{} `json:"weekday_text"`
} `json:"opening_hours,omitempty"`
Photos []struct {
Height int `json:"height"`
HTMLAttributions []string `json:"html_attributions"`
PhotoReference string `json:"photo_reference"`
Width int `json:"width"`
} `json:"photos,omitempty"`
PlaceID string `json:"place_id"`
Reference string `json:"reference"`
Scope string `json:"scope"`
Types []string `json:"types"`
Vicinity string `json:"vicinity"`
Rating float64 `json:"rating,omitempty"`
} `json:"results"`
Status string `json:"status"`
}
func searchPlaces(page string) {
apiKey := "API_KEY_HERE"
keyword := "residential+bank+33131"
latLong := "25.766144,-80.190589"
pageToken := page
var buffer bytes.Buffer
buffer.WriteString("https://maps.googleapis.com/maps/api/place/nearbysearch/json?location=")
buffer.WriteString(latLong)
buffer.WriteString("&radius=50000&keyword=")
buffer.WriteString(keyword)
buffer.WriteString("&key=")
buffer.WriteString(apiKey)
buffer.WriteString("&pagetoken=")
buffer.WriteString(pageToken)
query := buffer.String()
// PRINT CURRENT SEARCH
println("query is ", query)
println("\n")
// SEND REQUEST WITH QUERY
resp, err := http.Get(query)
if err != nil {
log.Fatal(err)
}
// CLOSE THE PRECLOSER THATS RETURNED WITH HTTP RESPONSE
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
log.Fatal(err)
}
res := GooglePlaces{}
json.Unmarshal([]byte(body), &res)
var listings bytes.Buffer
for i := 0; i < len(res.Results); i++ {
listings.WriteString(strconv.Itoa(i + 1))
listings.WriteString("\nName: ")
listings.WriteString(res.Results[i].Name)
listings.WriteString("\nAddress: ")
listings.WriteString(res.Results[i].Vicinity)
listings.WriteString("\nPlace ID: ")
listings.WriteString(res.Results[i].PlaceID)
listings.WriteString("\n---------------------------------------------\n\n")
}
listings.WriteString("\npagetoken is now:\n")
listings.WriteString(res.NextPageToken)
if err != nil {
log.Fatal(err)
}
fmt.Println(listings.String())
fmt.Printf("\n\n\n")
// LOOP BACK THROUGH FUNCTION
searchPlaces(res.NextPageToken)
}
func main() {
searchPlaces("")
}
Note that in the documentation for Google Place Search they state:
There is a short delay between when a next_page_token is issued, and when it will become valid.
But in your code you immediately send a request with the new token.
Adding a sleep for a few seconds before using the token solves the problem for me. I changed your code to
if res.NextPageToken != "" {
time.Sleep(3000 * time.Millisecond)
searchPlaces(res.NextPageToken)
} else {
fmt.Println("No more pagetoken, we're done.")
}
Unfortunately there's no documentation about for how long a token is valid.
I'm totally confused figuring out how I can mock a function, without using any additional packages like golang/mock. I'm just trying to learn how to do so but can't find many decent online resources.
Essentially, I followed this excellent article that explains how to use an interface to mock things.
As so, I've re-written the function I wanted to test. The function just inserts some data into datastore. My tests for that are ok - I can mock the function directly.
The issue I'm having is mocking it 'within' an http route I'm trying to test. Am using the Gin framework.
My router (simplified) looks like this:
func SetupRouter() *gin.Engine {
r := gin.Default()
r.Use(gin.Logger())
r.Use(gin.Recovery())
v1 := r.Group("v1")
v1.PATCH("operations/:id", controllers.UpdateOperation)
}
Which calls the UpdateOperation function:
func UpdateOperation(c *gin.Context) {
id := c.Param("id")
r := m.Response{}
str := m.OperationInfoer{}
err := m.FindAndCompleteOperation(str, id, r.Report)
if err == nil {
c.JSON(200, gin.H{
"message": "Operation completed",
})
}
}
So, I need to mock the FindAndCompleteOperation() function.
The main (simplified) functions looks like this:
func (oi OperationInfoer) FindAndCompleteOp(id string, report Report) error {
ctx := context.Background()
q := datastore.NewQuery("Operation").
Filter("Unique_Id =", id).
Limit(1)
var ops []Operation
if ts, err := db.Datastore.GetAll(ctx, q, &ops); err == nil {
{
if len(ops) > 0 {
ops[0].Id = ts[0].ID()
ops[0].Complete = true
// Do stuff
_, err := db.Datastore.Put(ctx, key, &o)
if err == nil {
log.Print("OPERATION COMPLETED")
}
}
}
}
err := errors.New("Not found")
return err
}
func FindAndCompleteOperation(ri OperationInfoer, id string, report Report) error {
return ri.FindAndCompleteOp(id, report)
}
type OperationInfoer struct{}
To test the route that updates the operation, I have something like so:
FIt("Return 200, updates operation", func() {
testRouter := SetupRouter()
param := make(url.Values)
param["access_token"] = []string{public_token}
report := m.Report{}
report.Success = true
report.Output = "my output"
jsonStr, _ := json.Marshal(report)
req, _ := http.NewRequest("PATCH", "/v1/operations/123?"+param.Encode(), bytes.NewBuffer(jsonStr))
resp := httptest.NewRecorder()
testRouter.ServeHTTP(resp, req)
Expect(resp.Code).To(Equal(200))
o := FakeResponse{}
json.NewDecoder(resp.Body).Decode(&o)
Expect(o.Message).To(Equal("Operation completed"))
})
Originally, I tried to cheat a bit and just tried something like this:
m.FindAndCompleteOperation = func(string, m.Report) error {
return nil
}
But that affects all the other tests etc.
I'm hoping someone can explain simply what the best way to mock the FindAndCompleteOperation function so I can test the routes, without relying on datastore etc.
I have another relevant, more informative answer to a similar question here, but here's an answer for your specific scenario:
Update your SetupRouter() function to take a function that can either be the real FindAndCompleteOperation function or a stub function:
Playground
package main
import "github.com/gin-gonic/gin"
// m.Response.Report
type Report struct {
// ...
}
// m.OperationInfoer
type OperationInfoer struct {
// ...
}
type findAndComplete func(s OperationInfoer, id string, report Report) error
func FindAndCompleteOperation(OperationInfoer, string, Report) error {
// ...
return nil
}
func SetupRouter(f findAndComplete) *gin.Engine {
r := gin.Default()
r.Group("v1").PATCH("/:id", func(c *gin.Context) {
if f(OperationInfoer{}, c.Param("id"), Report{}) == nil {
c.JSON(200, gin.H{"message": "Operation completed"})
}
})
return r
}
func main() {
r := SetupRouter(FindAndCompleteOperation)
if err := r.Run(":8080"); err != nil {
panic(err)
}
}
Test/mocking example
package main
import (
"encoding/json"
"net/http/httptest"
"strings"
"testing"
)
func TestUpdateRoute(t *testing.T) {
// build findAndComplete stub
var callCount int
var lastInfoer OperationInfoer
var lastID string
var lastReport Report
stub := func(s OperationInfoer, id string, report Report) error {
callCount++
lastInfoer = s
lastID = id
lastReport = report
return nil // or `fmt.Errorf("Err msg")` if you want to test fault path
}
// invoke endpoint
w := httptest.NewRecorder()
r := httptest.NewRequest(
"PATCH",
"/v1/id_value",
strings.NewReader(""),
)
SetupRouter(stub).ServeHTTP(w, r)
// check that the stub was invoked correctly
if callCount != 1 {
t.Fatal("Wanted 1 call; got", callCount)
}
if lastInfoer != (OperationInfoer{}) {
t.Fatalf("Wanted %v; got %v", OperationInfoer{}, lastInfoer)
}
if lastID != "id_value" {
t.Fatalf("Wanted 'id_value'; got '%s'", lastID)
}
if lastReport != (Report{}) {
t.Fatalf("Wanted %v; got %v", Report{}, lastReport)
}
// check that the correct response was returned
if w.Code != 200 {
t.Fatal("Wanted HTTP 200; got HTTP", w.Code)
}
var body map[string]string
if err := json.Unmarshal(w.Body.Bytes(), &body); err != nil {
t.Fatal("Unexpected error:", err)
}
if body["message"] != "Operation completed" {
t.Fatal("Wanted 'Operation completed'; got %s", body["message"])
}
}
You can't mock if you use globals that can't be mocked in an handler. Either your globals are mockable (i.e. declared as variables of interface type) or you need to use dependency injection.
func (oi OperationInfoer) FindAndCompleteOp(id string, report Report) error {...}
looks like a method of a struct, so you should be able to inject that struct into an handler, at the very least.
type OperationInfoer interface {
FindAndCompleteOp(id string, report Report) error
}
type ConcreteOperationInfoer struct { /* actual implementation */ }
func UpdateOperation(oi OperationInfoer) func(c *gin.Context) {
return func (c *gin.Context){
// the code
}
}
then mocking becomes a breeze in your tests :
UpdateOperation(mockOperationInfoer)(ginContext)
You can use a struct instead of closures
type UpdateOperationHandler struct {
Oi OperationInfoer
}
func (h UpdateOperationHandler ) UpdateOperation (c *gin.Context) {
h.Oi.FindAndCompleteOp(/* code */ )
}
The following Golang test never exits. I suspect it has something to do with a channel deadlock but being a go-noob, I am not very certain.
const userName = "xxxxxxxxxxxx"
func TestSynchroninze(t *testing.T) {
c, err := channel.New(github.ChannelName, authToken)
if err != nil {
t.Fatalf("Could not create channel: %s", err)
return
}
state := channel.NewState(nil)
ctx := context.Background()
ctx = context.WithValue(ctx, "userId", userName)
user := api.User{}
output, errs := c.Synchronize(state, ctx)
if err = <-errs; err != nil {
t.Fatalf("Error performing synchronize: %s", err)
return
}
for o := range output {
switch oo := o.Data.(type) {
case api.User:
user = oo
glog.Infof("we have a USER %s\n", user)
default:
t.Errorf("Encountered unexpected data type: %T", oo)
}
}
}
Here are the methods being tested.
type github struct {
client *api.Client
}
func newImplementation(t auth.UserToken) implementation.Implementation {
return &github{client: api.NewClient(t)}
}
// -------------------------------------------------------------------------------------
const (
kLastUserFetch = "lastUserFetch"
)
type synchronizeFunc func(implementation.MutableState, chan *implementation.Output, context.Context) error
// -------------------------------------------------------------------------------------
func (g *github) Synchronize(state implementation.MutableState, ctx context.Context) (<-chan *implementation.Output, <-chan error) {
output := make(chan *implementation.Output)
errors := make(chan error, 1) // buffer allows preflight errors
// Close output channels once we're done
defer func() {
go func() {
// wg.Wait()
close(errors)
close(output)
}()
}()
err := g.fetchUser(state, output, ctx)
if err != nil {
errors <- err
}
return output, errors
}
func (g *github) fetchUser(state implementation.MutableState, output chan *implementation.Output, ctx context.Context) error {
var err error
var user = api.User{}
userId, _ := ctx.Value("userId").(string)
user, err = g.client.GetUser(userId, ctx.Done())
if err == nil {
glog.Info("No error in fetchUser")
output <- &implementation.Output{Data: user}
state.SetTime(kLastUserFetch, time.Now())
}
return err
}
func (c *Client) GetUser(id string, quit <-chan struct{}) (user User, err error) {
// Execute request
var data []byte
data, err = c.get("users/"+id, nil, quit)
glog.Infof("USER DATA %s", data)
// Parse response
if err == nil && len(data) > 0 {
err = json.Unmarshal(data, &user)
data, _ = json.Marshal(user)
}
return
}
Here is what I see in the console (most of the user details removed)
I1228 13:25:05.291010 21313 client.go:177] GET https://api.github.com/users/xxxxxxxx
I1228 13:25:06.010085 21313 client.go:36] USER DATA {"login":"xxxxxxxx","id":00000000,"avatar_url":"https://avatars.githubusercontent.com/u/0000000?v=3",...}
I1228 13:25:06.010357 21313 github.go:90] No error in fetchUser
==========EDIT=============
Here is the relevant portion of the api package.
package api
type Client struct {
authToken auth.UserToken
http *http.Client
}
func NewClient(authToken auth.UserToken) *Client {
return &Client{
authToken: authToken,
http: auth.NewClient(authToken),
}
}
// -------------------------------------------------------------------------------------
type User struct {
Id int `json:"id,omitempty"`
Username string `json:"login,omitempty"`
Email string `json:"email,omitempty"`
FullName string `json:"name,omitempty"`
ProfilePicture string `json:"avatar_url,omitempty"`
Bio string `json:"bio,omitempty"`
Website string `json:"blog,omitempty"`
Company string `json:"company,omitempty"`
}
And the channel package
package channel
type Channel struct {
implementation.Descriptor
imp implementation.Implementation
}
// New returns a channel implementation with a given name and auth token.
func New(name string, token auth.UserToken) (*Channel, error) {
if desc, ok := implementation.Lookup(name); ok {
if imp := implementation.New(name, token); imp != nil {
return &Channel{Descriptor: desc, imp: imp}, nil
}
}
return nil, ErrInvalidChannel
}
and the implementation package...
package implementation
import "golang.org/x/net/context"
// -------------------------------------------------------------------------------------
// Implementation is the interface implemented by subpackages.
type Implementation interface {
// Synchronize performs a synchronization using the given state. A context parameters
// is provided to provide cancellation as well as implementation-specific behaviors.
//
// If a fatal error occurs (see package error definitions), the state can be discarded
// to prevent the persistence of an invalid state.
Synchronize(state MutableState, ctx context.Context) (<-chan *Output, <-chan error)
// FetchDetails gets details for a given timeline item. Any changes to the TimelineItem
// (including the Meta value) will be persisted.
FetchDetails(item *TimelineItem, ctx context.Context) (interface{}, error)
}
======Edit #2=======
This is the original Synchronize method. I removed some details in my testing to try and simplify the problem. By removing a go func call, I believe I introduced a new problem which could be confusing things.
Here is the original Synchronize method. There are some things with Wait Groups and a function array containing a single function because this method will eventually be synchronizing multiple functions.
func (g *github) Synchronize(state implementation.MutableState, ctx context.Context) (<-chan *implementation.Output, <-chan error) {
wg := sync.WaitGroup{}
output := make(chan *implementation.Output)
errors := make(chan error, 1) // buffer allows preflight errors
// Close output channels once we're done
defer func() {
go func() {
wg.Wait()
close(errors)
close(output)
}()
}()
// Perform fetch functions in separate routines
funcs := []synchronizeFunc{
g.fetchUser,
}
for _, f := range funcs {
wg.Add(1)
go func(f synchronizeFunc) {
defer wg.Done()
if err := f(state, output, ctx); err != nil {
errors <- err
}
}(f)
}
glog.Info("after go sync...")
return output, errors
}
I think the two problems are in
output <- &implementation.Output{Data: user}
the channel does not have a buffer. It will block until some other goroutine reads from it. But in your code is the same goroutine so it will block.
and second:
// Close output channels once we're done
defer func() {
go func() {
// wg.Wait()
close(errors)
close(output)
}()
}()
you launch a go routine when the routine exits. The goroutine is scheduled, the function returns but it never calls the goroutine.
I would suggest to unify all that logic in one:
func (g *github) Synchronize(state implementation.MutableState, ctx context.Context) (<-chan *implementation.Output, <-chan error) {
output := make(chan *implementation.Output)
errors := make(chan error, 1) // buffer allows preflight errors
go func() {
defer close(output)
defer close(errors)
err := g.fetchUser(state, output, ctx)
if err != nil {
errors <- err
}
}()
return output, errors
}
I would like to run WMI queries from Go. There are ways to call DLL functions from Go. My understanding is that there must be some DLL somewhere which, with the correct call, will return some data I can parse and use. I'd prefer to avoid calling into C or C++, especially since I would guess those are wrappers over the Windows API itself.
I've examined the output of dumpbin.exe /exports c:\windows\system32\wmi.dll, and the following entry looks promising:
WmiQueryAllDataA (forwarded to wmiclnt.WmiQueryAllDataA)
However I'm not sure what to do from here. What arguments does this function take? What does it return? Searching for WmiQueryAllDataA is not helpful. And that name only appears in a comment of c:\program files (x86)\windows kits\8.1\include\shared\wmistr.h, but with no function signature.
Are there better methods? Is there another DLL? Am I missing something? Should I just use a C wrapper?
Running a WMI query in Linqpad with .NET Reflector shows the use of WmiNetUtilsHelper:ExecQueryWmi (and a _f version), but neither have a viewable implementation.
Update: use the github.com/StackExchange/wmi package which uses the solution in the accepted answer.
Welcome to the wonderful world of COM, Object Oriented Programming in C from when C++ was "a young upstart".
On github mattn has thrown together a little wrapper in Go, which I used to throw together a quick example program. "This repository was created for experimentation and should be considered unstable." instills all sorts of confidence.
I'm leaving out a lot of error checking. Trust me when I say, you'll want to add it back.
package main
import (
"github.com/mattn/go-ole"
"github.com/mattn/go-ole/oleutil"
)
func main() {
// init COM, oh yeah
ole.CoInitialize(0)
defer ole.CoUninitialize()
unknown, _ := oleutil.CreateObject("WbemScripting.SWbemLocator")
defer unknown.Release()
wmi, _ := unknown.QueryInterface(ole.IID_IDispatch)
defer wmi.Release()
// service is a SWbemServices
serviceRaw, _ := oleutil.CallMethod(wmi, "ConnectServer")
service := serviceRaw.ToIDispatch()
defer service.Release()
// result is a SWBemObjectSet
resultRaw, _ := oleutil.CallMethod(service, "ExecQuery", "SELECT * FROM Win32_Process")
result := resultRaw.ToIDispatch()
defer result.Release()
countVar, _ := oleutil.GetProperty(result, "Count")
count := int(countVar.Val)
for i :=0; i < count; i++ {
// item is a SWbemObject, but really a Win32_Process
itemRaw, _ := oleutil.CallMethod(result, "ItemIndex", i)
item := itemRaw.ToIDispatch()
defer item.Release()
asString, _ := oleutil.GetProperty(item, "Name")
println(asString.ToString())
}
}
The real meat is the call to ExecQuery, I happen to grab Win32_Process from the available classes because it's easy to understand and print.
On my machine, this prints:
System Idle Process
System
smss.exe
csrss.exe
wininit.exe
services.exe
lsass.exe
svchost.exe
svchost.exe
atiesrxx.exe
svchost.exe
svchost.exe
svchost.exe
svchost.exe
svchost.exe
spoolsv.exe
svchost.exe
AppleOSSMgr.exe
AppleTimeSrv.exe
... and so on
go.exe
main.exe
I'm not running it elevated or with UAC disabled, but some WMI providers are gonna require a privileged user.
I'm also not 100% that this won't leak a little, you'll want to dig into that. COM objects are reference counted, so defer should be a pretty good fit there (provided the method isn't crazy long running) but go-ole may have some magic inside I didn't notice.
I'm commenting over a year later, but there is a solution here on github (and posted below for posterity).
// +build windows
/*
Package wmi provides a WQL interface for WMI on Windows.
Example code to print names of running processes:
type Win32_Process struct {
Name string
}
func main() {
var dst []Win32_Process
q := wmi.CreateQuery(&dst, "")
err := wmi.Query(q, &dst)
if err != nil {
log.Fatal(err)
}
for i, v := range dst {
println(i, v.Name)
}
}
*/
package wmi
import (
"bytes"
"errors"
"fmt"
"log"
"os"
"reflect"
"runtime"
"strconv"
"strings"
"sync"
"time"
"github.com/mattn/go-ole"
"github.com/mattn/go-ole/oleutil"
)
var l = log.New(os.Stdout, "", log.LstdFlags)
var (
ErrInvalidEntityType = errors.New("wmi: invalid entity type")
lock sync.Mutex
)
// QueryNamespace invokes Query with the given namespace on the local machine.
func QueryNamespace(query string, dst interface{}, namespace string) error {
return Query(query, dst, nil, namespace)
}
// Query runs the WQL query and appends the values to dst.
//
// dst must have type *[]S or *[]*S, for some struct type S. Fields selected in
// the query must have the same name in dst. Supported types are all signed and
// unsigned integers, time.Time, string, bool, or a pointer to one of those.
// Array types are not supported.
//
// By default, the local machine and default namespace are used. These can be
// changed using connectServerArgs. See
// http://msdn.microsoft.com/en-us/library/aa393720.aspx for details.
func Query(query string, dst interface{}, connectServerArgs ...interface{}) error {
dv := reflect.ValueOf(dst)
if dv.Kind() != reflect.Ptr || dv.IsNil() {
return ErrInvalidEntityType
}
dv = dv.Elem()
mat, elemType := checkMultiArg(dv)
if mat == multiArgTypeInvalid {
return ErrInvalidEntityType
}
lock.Lock()
defer lock.Unlock()
runtime.LockOSThread()
defer runtime.UnlockOSThread()
err := ole.CoInitializeEx(0, ole.COINIT_MULTITHREADED)
if err != nil {
oleerr := err.(*ole.OleError)
// S_FALSE = 0x00000001 // CoInitializeEx was already called on this thread
if oleerr.Code() != ole.S_OK && oleerr.Code() != 0x00000001 {
return err
}
} else {
// Only invoke CoUninitialize if the thread was not initizlied before.
// This will allow other go packages based on go-ole play along
// with this library.
defer ole.CoUninitialize()
}
unknown, err := oleutil.CreateObject("WbemScripting.SWbemLocator")
if err != nil {
return err
}
defer unknown.Release()
wmi, err := unknown.QueryInterface(ole.IID_IDispatch)
if err != nil {
return err
}
defer wmi.Release()
// service is a SWbemServices
serviceRaw, err := oleutil.CallMethod(wmi, "ConnectServer", connectServerArgs...)
if err != nil {
return err
}
service := serviceRaw.ToIDispatch()
defer serviceRaw.Clear()
// result is a SWBemObjectSet
resultRaw, err := oleutil.CallMethod(service, "ExecQuery", query)
if err != nil {
return err
}
result := resultRaw.ToIDispatch()
defer resultRaw.Clear()
count, err := oleInt64(result, "Count")
if err != nil {
return err
}
// Initialize a slice with Count capacity
dv.Set(reflect.MakeSlice(dv.Type(), 0, int(count)))
var errFieldMismatch error
for i := int64(0); i < count; i++ {
err := func() error {
// item is a SWbemObject, but really a Win32_Process
itemRaw, err := oleutil.CallMethod(result, "ItemIndex", i)
if err != nil {
return err
}
item := itemRaw.ToIDispatch()
defer itemRaw.Clear()
ev := reflect.New(elemType)
if err = loadEntity(ev.Interface(), item); err != nil {
if _, ok := err.(*ErrFieldMismatch); ok {
// We continue loading entities even in the face of field mismatch errors.
// If we encounter any other error, that other error is returned. Otherwise,
// an ErrFieldMismatch is returned.
errFieldMismatch = err
} else {
return err
}
}
if mat != multiArgTypeStructPtr {
ev = ev.Elem()
}
dv.Set(reflect.Append(dv, ev))
return nil
}()
if err != nil {
return err
}
}
return errFieldMismatch
}
// ErrFieldMismatch is returned when a field is to be loaded into a different
// type than the one it was stored from, or when a field is missing or
// unexported in the destination struct.
// StructType is the type of the struct pointed to by the destination argument.
type ErrFieldMismatch struct {
StructType reflect.Type
FieldName string
Reason string
}
func (e *ErrFieldMismatch) Error() string {
return fmt.Sprintf("wmi: cannot load field %q into a %q: %s",
e.FieldName, e.StructType, e.Reason)
}
var timeType = reflect.TypeOf(time.Time{})
// loadEntity loads a SWbemObject into a struct pointer.
func loadEntity(dst interface{}, src *ole.IDispatch) (errFieldMismatch error) {
v := reflect.ValueOf(dst).Elem()
for i := 0; i < v.NumField(); i++ {
f := v.Field(i)
isPtr := f.Kind() == reflect.Ptr
if isPtr {
ptr := reflect.New(f.Type().Elem())
f.Set(ptr)
f = f.Elem()
}
n := v.Type().Field(i).Name
if !f.CanSet() {
return &ErrFieldMismatch{
StructType: f.Type(),
FieldName: n,
Reason: "CanSet() is false",
}
}
prop, err := oleutil.GetProperty(src, n)
if err != nil {
errFieldMismatch = &ErrFieldMismatch{
StructType: f.Type(),
FieldName: n,
Reason: "no such struct field",
}
continue
}
defer prop.Clear()
switch val := prop.Value().(type) {
case int, int64:
var v int64
switch val := val.(type) {
case int:
v = int64(val)
case int64:
v = val
default:
panic("unexpected type")
}
switch f.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
f.SetInt(v)
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
f.SetUint(uint64(v))
default:
return &ErrFieldMismatch{
StructType: f.Type(),
FieldName: n,
Reason: "not an integer class",
}
}
case string:
iv, err := strconv.ParseInt(val, 10, 64)
switch f.Kind() {
case reflect.String:
f.SetString(val)
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
if err != nil {
return err
}
f.SetInt(iv)
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
if err != nil {
return err
}
f.SetUint(uint64(iv))
case reflect.Struct:
switch f.Type() {
case timeType:
if len(val) == 25 {
mins, err := strconv.Atoi(val[22:])
if err != nil {
return err
}
val = val[:22] + fmt.Sprintf("%02d%02d", mins/60, mins%60)
}
t, err := time.Parse("20060102150405.000000-0700", val)
if err != nil {
return err
}
f.Set(reflect.ValueOf(t))
}
}
case bool:
switch f.Kind() {
case reflect.Bool:
f.SetBool(val)
default:
return &ErrFieldMismatch{
StructType: f.Type(),
FieldName: n,
Reason: "not a bool",
}
}
default:
typeof := reflect.TypeOf(val)
if isPtr && typeof == nil {
break
}
return &ErrFieldMismatch{
StructType: f.Type(),
FieldName: n,
Reason: fmt.Sprintf("unsupported type (%T)", val),
}
}
}
return errFieldMismatch
}
type multiArgType int
const (
multiArgTypeInvalid multiArgType = iota
multiArgTypeStruct
multiArgTypeStructPtr
)
// checkMultiArg checks that v has type []S, []*S for some struct type S.
//
// It returns what category the slice's elements are, and the reflect.Type
// that represents S.
func checkMultiArg(v reflect.Value) (m multiArgType, elemType reflect.Type) {
if v.Kind() != reflect.Slice {
return multiArgTypeInvalid, nil
}
elemType = v.Type().Elem()
switch elemType.Kind() {
case reflect.Struct:
return multiArgTypeStruct, elemType
case reflect.Ptr:
elemType = elemType.Elem()
if elemType.Kind() == reflect.Struct {
return multiArgTypeStructPtr, elemType
}
}
return multiArgTypeInvalid, nil
}
func oleInt64(item *ole.IDispatch, prop string) (int64, error) {
v, err := oleutil.GetProperty(item, prop)
if err != nil {
return 0, err
}
defer v.Clear()
i := int64(v.Val)
return i, nil
}
// CreateQuery returns a WQL query string that queries all columns of src. where
// is an optional string that is appended to the query, to be used with WHERE
// clauses. In such a case, the "WHERE" string should appear at the beginning.
func CreateQuery(src interface{}, where string) string {
var b bytes.Buffer
b.WriteString("SELECT ")
s := reflect.Indirect(reflect.ValueOf(src))
t := s.Type()
if s.Kind() == reflect.Slice {
t = t.Elem()
}
if t.Kind() != reflect.Struct {
return ""
}
var fields []string
for i := 0; i < t.NumField(); i++ {
fields = append(fields, t.Field(i).Name)
}
b.WriteString(strings.Join(fields, ", "))
b.WriteString(" FROM ")
b.WriteString(t.Name())
b.WriteString(" " + where)
return b.String()
}
To access the winmgmts object or a namespace (which is the same), you can use the code below. Basically, you need to specify the namespace as parameter, which is not documented properly in go-ole.
In the code below, you can also see how to access a class within this namespace and execute a method.
package main
import (
"log"
"github.com/go-ole/go-ole"
"github.com/go-ole/go-ole/oleutil"
)
func main() {
ole.CoInitializeEx(0, ole.COINIT_MULTITHREADED)
defer ole.CoUninitialize()
unknown, err := oleutil.CreateObject("WbemScripting.SWbemLocator")
if err != nil {
log.Panic(err)
}
defer unknown.Release()
wmi, err := unknown.QueryInterface(ole.IID_IDispatch)
if err != nil {
log.Panic(err)
}
defer wmi.Release()
// Connect to namespace
// root/PanasonicPC = winmgmts:\\.\root\PanasonicPC
serviceRaw, err := oleutil.CallMethod(wmi, "ConnectServer", nil, "root/PanasonicPC")
if err != nil {
log.Panic(err)
}
service := serviceRaw.ToIDispatch()
defer serviceRaw.Clear()
// Get class
setBiosRaw, err := oleutil.CallMethod(service, "Get", "SetBIOS4Conf")
if err != nil {
log.Panic(err)
}
setBios := setBiosRaw.ToIDispatch()
defer setBiosRaw.Clear()
// Run method
resultRaw, err := oleutil.CallMethod(setBios, "AccessAuthorization", "letmein")
resultVal := resultRaw.Value().(int32)
log.Println("Return Code:", resultVal)
}
import(
"os/exec"
)
func (lcu *LCU) GrabToken() {
cmd := exec.Command("powershell", "$cmdline = Get-WmiObject -Class Win32_Process")
out, err := cmd.CombinedOutput()
if err != nil {
fmt.Println(err)
}
outstr := string(out)
}