Add publig IP getter
All checks were successful
continuous-integration/drone/push Build is passing

Ref #3

This commit uses a GET query to ifconfig.me in order to get the current
public IP. It also modifies the initialization message to send the
current public IP to the Telegram channel instead of a simple message.
This commit is contained in:
Melora Hugues 2023-01-25 21:06:00 +01:00
parent 54de3b84cd
commit 568aaa9f8c
2 changed files with 61 additions and 1 deletions

View file

@ -6,6 +6,7 @@ import (
"time"
"git.faercol.me/faercol/public-ip-tracker/tracker/config"
"git.faercol.me/faercol/public-ip-tracker/tracker/ip"
"github.com/ahugues/go-telegram-api/bot"
)
@ -14,10 +15,16 @@ type Notifier struct {
cancel context.CancelFunc
tgBot *bot.ConcreteBot
notifChannel int64
ipGetter ip.Getter
}
func (n *Notifier) SendInitMessage() error {
initMsg := fmt.Sprintf("Public IP tracked initialized at %v", time.Now())
publicIP, err := n.ipGetter.GetCurrentPublicIP(n.ctx)
if err != nil {
return fmt.Errorf("failed to get current public IP: %w", err)
}
initMsg := fmt.Sprintf("Public IP tracker initialized at %v, public IP is %s", time.Now(), publicIP)
if err := n.tgBot.SendMessage(n.ctx, n.notifChannel, initMsg); err != nil {
return fmt.Errorf("failed to send initialization message: %w", err)
}
@ -33,5 +40,6 @@ func New(ctx context.Context, config *config.Config) *Notifier {
cancel: cancel,
tgBot: tgBot,
notifChannel: config.Telegram.ChannelID,
ipGetter: ip.New(),
}
}

52
tracker/ip/ip.go Normal file
View file

@ -0,0 +1,52 @@
package ip
import (
"bytes"
"context"
"fmt"
"io"
"net"
"net/http"
)
const ifconfigURL = "https://ifconfig.me"
const httpMaxRead = 100
// TODO: use a struct, but a baseHTTPClient inside it to perform unit tests
type Getter interface {
GetCurrentPublicIP(ctx context.Context) (net.IP, error)
}
type concreteIPGetter struct {
}
func (c *concreteIPGetter) GetCurrentPublicIP(ctx context.Context) (net.IP, error) {
req, err := http.NewRequestWithContext(ctx, http.MethodGet, ifconfigURL, nil)
if err != nil {
return nil, fmt.Errorf("failed to prepare public IP request: %w", err)
}
resp, err := http.DefaultClient.Do(req)
if err != nil {
return nil, fmt.Errorf("failed to get current IP from ifconfig: %w", err)
}
if resp.ContentLength > httpMaxRead {
return nil, fmt.Errorf("response too big: %d/%d", resp.ContentLength, httpMaxRead)
}
buf := bytes.NewBuffer([]byte{})
if _, err := io.CopyN(buf, resp.Body, resp.ContentLength); err != nil {
return nil, fmt.Errorf("error parsing body: %w", err)
}
content := string(buf.Bytes())
res := net.ParseIP(content)
if res == nil {
return nil, fmt.Errorf("got an invalid public IP %q", content)
}
return res, nil
}
func New() *concreteIPGetter {
return &concreteIPGetter{}
}