How to parse QueryString - go

I have a string such as username=Test1234&currency=THB and I need to get value of username or currency
qry, _ := url.Parse(string(qryString))


An example is as follows:
package main
import (
"fmt"
"net/url"
)
func main() {
address := "http://example.com?name=poloxue&age=11"
u, err := url.Parse(address)
if err != nil {
panic(err)
}
fmt.Println(u.RawQuery)
q, err := url.ParseQuery(u.RawQuery)
if err != nil {
panic(err)
}
fmt.Println(q.Get("name"))
}
Output:
name=poloxue&age=11
poloxue

Related

How proper get content from url in GO?

For example I need content from page https://aliexpress.ru/item/4001275226820.html
In Postman and in browser I get html content of page
But when I try use GO i can`t get content
package main
import (
"fmt"
"io/ioutil"
"net/http"
)
func main() {
resp, err := http.Get("https://aliexpress.ru/item/4001275226820.html")
defer resp.Body.Close()
if err != nil {panic(err)}
html, err1 := ioutil.ReadAll(resp.Body)
if err1 != nil {panic(err1)}
fmt.Printf("%s\n", html)
}
But get panic "stopped after 10 redirects"
what am I doing wrong?

The below code gets me a 200 response. You might be able to simplify it, but should be enough to get you started:
package main
import (
"fmt"
"net/http"
)
func cookies() ([]*http.Cookie, error) {
req, err := http.NewRequest(
"HEAD", "https://login.aliexpress.ru/sync_cookie_write.htm", nil,
)
if err != nil {
return nil, err
}
val := req.URL.Query()
val.Set("acs_random_token", "1")
req.URL.RawQuery = val.Encode()
res, err := new(http.Transport).RoundTrip(req)
if err != nil {
return nil, err
}
return res.Cookies(), nil
}
func main() {
req, err := http.NewRequest(
"HEAD", "https://aliexpress.ru/item/4001275226820.html", nil,
)
if err != nil {
panic(err)
}
cooks, err := cookies()
if err != nil {
panic(err)
}
for _, cook := range cooks {
if cook.Name == "xman_f" {
req.AddCookie(cook)
}
}
res, err := new(http.Transport).RoundTrip(req)
if err != nil {
panic(err)
}
fmt.Printf("%+v\n", res)
}

golang os.Close() function works, but os.Remove() function does not

I am trying to create a file, open it, do some processing on it & close it. Finally, I want to delete the file.
All these operations are executed successfully, except the deletion.
My code is:
package main
import (
"fmt"
"os"
"log"
)
func main() {
fmt.Println("Hello")
metaFileName := "./metadata.txt"
_, err2 := os.Create(metaFileName)
if err2 != nil {
log.Fatal(err2)
}
openMetaFile, err := os.Open(metaFileName)
if err != nil {
log.Fatal(err)
}
err = openMetaFile.Close()
if err != nil {
log.Fatal(err)
}
err = os.Remove(metaFileName)
if err != nil {
log.Fatal(err)
}
fmt.Println("Success")
}
The output is:
Hello
2020/08/24 00:00:00 remove ./metadata.txt: The process cannot access the file be
cause it is being used by another process.
I am clueless about this

The problem is related to the first opened file.
package main
import (
"fmt"
"log"
"os"
)
const metaFileName = "./metadata.txt"
func main() {
var (
err error
tmpFile, openMetaFile *os.File
)
fmt.Println("Hello")
if tmpFile, err = os.Create(metaFileName); err != nil {
log.Fatal(err)
}
if err = tmpFile.Close(); err != nil {
log.Fatal(err)
}
if openMetaFile, err = os.Open(metaFileName); err != nil {
log.Fatal(err)
}
if err = openMetaFile.Close(); err != nil {
log.Fatal(err)
}
if err = os.Remove(metaFileName); err != nil {
log.Fatal(err)
}
fmt.Println("Success")
}
As you can see, i've used the var a in order to close the first file that you have opened. The result is following one:
Hello
Success

How do i find and replace something inside a quote?

I found this Go program which is going to find and remove text in a file and I need some help.
How do I modify this program to get the following and replace it?
I tried a couple of things but the issue is there is another quote inside of the string.
Current:
{"telephone_numbers":["1-
Future:
{"telephone_numbers":["+1-
Find and replace script.
package main
import (
"fmt"
"io/ioutil"
"os"
"path/filepath"
"strings"
)
func visit(path string, fi os.FileInfo, err error) error {
if err != nil {
return err
}
if !!fi.IsDir() {
return nil //
}
matched, err := filepath.Match("*.txt", fi.Name())
if err != nil {
panic(err)
return err
}
if matched {
read, err := ioutil.ReadFile(path)
if err != nil {
panic(err)
}
//fmt.Println(string(read))
fmt.Println(path)
newContents := strings.Replace(string(read), "old", "new", -1)
fmt.Println(newContents)
err = ioutil.WriteFile(path, []byte(newContents), 0)
if err != nil {
panic(err)
}
}
return nil
}
func main() {
err := filepath.Walk(".", visit)
if err != nil {
panic(err)
}
}

This is the answer.
package main
import (
"fmt"
"io/ioutil"
"os"
"path/filepath"
"strings"
)
func visit(path string, fi os.FileInfo, err error) error {
if err != nil {
return err
}
if !!fi.IsDir() {
return nil //
}
matched, err := filepath.Match("*.txt", fi.Name())
if err != nil {
panic(err)
return err
}
if matched {
read, err := ioutil.ReadFile(path)
if err != nil {
panic(err)
}
//fmt.Println(string(read))
fmt.Println(path)
newContents := strings.Replace(string(read), `{"telephone_numbers":["1-`, `{"telephone_numbers":["+1-`, -1)
fmt.Println(newContents)
err = ioutil.WriteFile(path, []byte(newContents), 0)
if err != nil {
panic(err)
}
}
return nil
}
func main() {
err := filepath.Walk(".", visit)
if err != nil {
panic(err)
}
}

Get permanent MAC address

Is there an easy way to get the permanent MAC Address using Go?

package main
import (
"fmt"
"log"
"net"
)
func getMacAddr() ([]string, error) {
ifas, err := net.Interfaces()
if err != nil {
return nil, err
}
var as []string
for _, ifa := range ifas {
a := ifa.HardwareAddr.String()
if a != "" {
as = append(as, a)
}
}
return as, nil
}
func main() {
as, err := getMacAddr()
if err != nil {
log.Fatal(err)
}
for _, a := range as {
fmt.Println(a)
}
}

how to generate multiple uuid and md5 files in golang

Hi I've generated Md5 and uuid in golang but now I want generate it for multiple files using command line arguments, so what exactly I've to do. This is how I've generated my md5 and uuid:
package main
import (
"crypto/rand"
"crypto/md5"
"fmt"
"io"
"os"
"log"
"text/template"
)
type Data struct {
Uuid string
Md5 string
}
func main() {
uuid, err := newUUID()
if err != nil {
fmt.Printf("error: %v\n", err)
}
fmt.Printf("UUID: %s\n", uuid)
md5 := Getmd5(uuid)
fmt.Printf("Checksum: %s\n",md5)
fillData := Data{uuid, md5}
file, err := os.Create("text.txt")
if err != nil {
return
}
defer file.Close()
templ, err := template.ParseFiles("template.html")
if err !=nil{
log.Fatalln(err)
}
err = templ.Execute(file,fillData)
if err != nil{
log.Fatalln(err)
}
}
// newUUID generates a random UUID according to RFC 4122
func newUUID() (string, error) {
uuid := make([]byte, 16)
n, err := io.ReadFull(rand.Reader, uuid)
if n != len(uuid) || err != nil {
return "", err
}
// variant bits
uuid[8] = uuid[8]&^0xc0 | 0x80
// version 4 (pseudo-random)
uuid[6] = uuid[6]&^0xf0 | 0x40
return fmt.Sprintf("%x-%x-%x-%x-%x", uuid[0:4], uuid[4:6], uuid[6:8], uuid[8:10], uuid[10:]), nil
}
func Getmd5(uuid string) (string) {
data := []byte(uuid)
//md5_buffer := fmt.Sprintf("%x", md5.Sum(data))
md5_buffer := md5.Sum(data)
return fmt.Sprintf("{0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x};\n",md5_buffer[0:1],
md5_buffer[1:2],md5_buffer[2:3],md5_buffer[3:4],md5_buffer[4:5],md5_buffer[5:6],md5_buffer[6:7],md5_buffer[7:8],
md5_buffer[8:9],md5_buffer[9:10],md5_buffer[10:11],md5_buffer[11:12],md5_buffer[12:13],md5_buffer[13:14],md5_buffer[14:15],
md5_buffer[15:16])
}
Can anyone help me out?

You can use os.Args to accept command line arguements
os.Args provides access to raw command-line arguments. Note that the first value in this slice is the path to the program, and os.Args[1:] holds the arguments to the program.
Your program will look like this, have a look at createFile and getNumberOfFiles functions and the main
package main
import (
"crypto/md5"
"crypto/rand"
"errors"
"fmt"
"io"
"log"
"os"
"strconv"
"text/template"
)
type Data struct {
Uuid string
Md5 string
}
func createFile(uuid string) {
md5 := Getmd5(uuid)
fmt.Printf("Checksum: %s\n", md5)
fillData := Data{uuid, md5}
file, err := os.Create(uuid + ".txt")
if err != nil {
return
}
defer file.Close()
templ, err := template.ParseFiles("template.html")
if err != nil {
log.Fatalln(err)
}
err = templ.Execute(file, fillData)
if err != nil {
log.Fatalln(err)
}
}
func getNumberOfFiles() (num int, err error) {
if len(os.Args) == 1 {
return 0, errors.New("Not enough arguements")
}
if num, err = strconv.Atoi(os.Args[1]); err != nil {
return
}
return num, nil
}
func main() {
numberOfFiles, err := getNumberOfFiles()
if err != nil {
fmt.Println(err.Error())
}
fmt.Printf("Creating %d files", numberOfFiles)
for i := 0; i < numberOfFiles; i++ {
uuid, err := newUUID()
if err != nil {
fmt.Printf("error: %v\n", err)
}
createFile(uuid)
}
}
// newUUID generates a random UUID according to RFC 4122
func newUUID() (string, error) {
uuid := make([]byte, 16)
n, err := io.ReadFull(rand.Reader, uuid)
if n != len(uuid) || err != nil {
return "", err
}
// variant bits
uuid[8] = uuid[8]&^0xc0 | 0x80
// version 4 (pseudo-random)
uuid[6] = uuid[6]&^0xf0 | 0x40
return fmt.Sprintf("%x-%x-%x-%x-%x", uuid[0:4], uuid[4:6], uuid[6:8], uuid[8:10], uuid[10:]), nil
}
func Getmd5(uuid string) string {
data := []byte(uuid)
//md5_buffer := fmt.Sprintf("%x", md5.Sum(data))
md5_buffer := md5.Sum(data)
return fmt.Sprintf("{0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x,0x%x};\n", md5_buffer[0:1],
md5_buffer[1:2], md5_buffer[2:3], md5_buffer[3:4], md5_buffer[4:5], md5_buffer[5:6], md5_buffer[6:7], md5_buffer[7:8],
md5_buffer[8:9], md5_buffer[9:10], md5_buffer[10:11], md5_buffer[11:12], md5_buffer[12:13], md5_buffer[13:14], md5_buffer[14:15],
md5_buffer[15:16])
}

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