stay In the last tutorial We created a robot that automatically responds to messages. When a user sends a message "Hello,World!", the robot automatically responds to the same message!

After learning according to this tutorial, your robot will accept the encrypted currency sent by the user, and then immediately return to the user.
The complete code is as follows:

main.go

fpackage main

import (
    "context"
    "encoding/base64"
    "encoding/json"
    "log"
    "github.com/MooooonStar/mixin-sdk-go/messenger"
    mixin "github.com/MooooonStar/mixin-sdk-go/network"
)

type Listener struct {
    *messenger.Messenger
}

// interface to implement if you want to handle the message
func (l *Listener) OnMessage(ctx context.Context, msg messenger.MessageView, userId string) error {
    data, err := base64.StdEncoding.DecodeString(msg.Data)
    if err != nil {
        return err
    }
    if msg.Category == "SYSTEM_ACCOUNT_SNAPSHOT" {
        var transfer messenger.TransferView
        if err := json.Unmarshal(data, &transfer); err != nil {
            return err
        }
        log.Println("I got a coin: ", transfer.Amount)
        mixin.Transfer(msg.UserId,transfer.Amount,transfer.AssetId,"",messenger.UuidNewV4().String(),
                                    PinCode,PinToken,UserId,SessionId,PrivateKey)
        return nil
        // return l.SendPlainText(ctx, msg.ConversationId, msg.UserId, string(data))
    } else if msg.Category == "PLAIN_TEXT" {
        log.Printf("I got a message, it said: %s", string(data))
        if string(data) == "g" {
            payLinkEOS := "https://mixin.one/pay?recipient=" +
                             msg.UserId  + "&asset=" +
                             "6cfe566e-4aad-470b-8c9a-2fd35b49c68d"   +
                             "&amount=" + "0.1" +
                             "&trace="  + messenger.UuidNewV4().String() +
                             "&memo="
          payLinkBTC := "https://mixin.one/pay?recipient=" +
                             msg.UserId  + "&asset=" +
                             "c6d0c728-2624-429b-8e0d-d9d19b6592fa"   +
                             "&amount=" + "0.001" +
                             "&trace="  + messenger.UuidNewV4().String() +
                             "&memo="
          log.Println(payLinkBTC)
            BtnEOS := messenger.Button{Label: "Pay EOS 0.1", Color: "#0080FF", Action: payLinkEOS}
            BtnBTC := messenger.Button{Label: "Pay BTC 0.0001", Color: "#00FF80", Action: payLinkBTC}
            if err := l.SendAppButtons(ctx, msg.ConversationId, msg.UserId, BtnEOS, BtnBTC); err != nil {
                return err
            }
            return nil
        } else if string(data) == "a"  {
            card := messenger.AppCard{Title: "Pay BTC 0.0001", Description: "topay", Action: "http://www.google.cn",
                IconUrl: "https://images.mixin.one/HvYGJsV5TGeZ-X9Ek3FEQohQZ3fE9LBEBGcOcn4c4BNHovP4fW4YB97Dg5LcXoQ1hUjMEgjbl1DPlKg1TW7kK6XP=s128"}
            if err := l.SendAppCard(ctx, msg.ConversationId, msg.UserId, card); err != nil {
                return err
            }
            return nil
        } else if string(data) == "r" {
            mixin.Transfer(msg.UserId,"0.0001","c6d0c728-2624-429b-8e0d-d9d19b6592fa","",messenger.UuidNewV4().String(),
                                        PinCode,PinToken,UserId,SessionId,PrivateKey)
            return nil
        } else { return l.SendPlainText(ctx, msg.ConversationId, msg.UserId, string(data)) }
    } else {
        log.Println("Unknown message!", msg.Category)
        return err
    }
}
const (
    UserId    = "21042518-85c7-4903-bb19-f311813d1f51"
    PinCode   = "911424"
    SessionId = "4267b63d-3daa-449e-bc13-970aa0357776"
    PinToken  = "gUUxpm3fPRVkKZNwA/gk10SHHDtR8LmxO+N6KbsZ/jymmwwVitUHKgLbk1NISdN8jBvsYJgF/5hbkxNnCJER5XAZ0Y35gsAxBOgcFN8otsV6F0FAm5TnWN8YYCqeFnXYJnqmI30IXJTAgMhliLj7iZsvyY/3htaHUUuN5pQ5F5s="
    //please delele the blank of PrivateKey the before each line
    PrivateKey = `-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----`
)


func main() {
    ctx := context.Background()
    m := messenger.NewMessenger(UserId, SessionId, PrivateKey)
    l := &Listener{m}
    go m.Run(ctx, l)
    select {}
}

Hello, Bitcoin!

Compile and execute in the project directory

cd mixin_labs-go-bot
go build
./mixin_labs-go-bot

Developers can transfer bitcoins to robots through message panels. When the robots receive bitcoins, they return them to users immediately.

In fact, the user can send any currency to the robot, and it can be returned immediately!

Source Code Interpretation

if msg.Category == "SYSTEM_ACCOUNT_SNAPSHOT" {
  var transfer messenger.TransferView
  if err := json.Unmarshal(data, &transfer); err != nil {
    return err
  }
  log.Println("I got a coin: ", transfer.Amount)
  mixin.Transfer(msg.UserId,transfer.Amount,transfer.AssetId,"",messenger.UuidNewV4().String(),
                PinCode,PinToken,UserId,SessionId,PrivateKey)
  return nil
  // return l.SendPlainText(ctx, msg.ConversationId, msg.UserId, string(data))
}

Call SDK mixin.Transfer to return the currency to the user!

Advanced Usage

APP_BUTTON_GROUP

In some application scenarios, for example, there is an exchange that wants to provide currency exchange services, such as converting bitcoins into Ethernet shops, EOS, bitcoin cash, etc.
You want to show users a set of buttons that represent different currencies and different quantities. APP_BUTTON_GROUP can help you do this.

payLinkEOS := "https://mixin.one/pay?recipient=" +
         msg.UserId  + "&asset=" +
         "6cfe566e-4aad-470b-8c9a-2fd35b49c68d"   +
         "&amount=" + "0.1" +
         "&trace="  + messenger.UuidNewV4().String() +
         "&memo="
payLinkBTC := "https://mixin.one/pay?recipient=" +
         msg.UserId  + "&asset=" +
         "c6d0c728-2624-429b-8e0d-d9d19b6592fa"   +
         "&amount=" + "0.001" +
         "&trace="  + messenger.UuidNewV4().String() +
         "&memo="
log.Println(payLinkBTC)
BtnEOS := messenger.Button{Label: "Pay EOS 0.1", Color: "#0080FF", Action: payLinkEOS}
BtnBTC := messenger.Button{Label: "Pay BTC 0.001", Color: "#00FF80", Action: payLinkBTC}
if err := l.SendAppButtons(ctx, msg.ConversationId, msg.UserId, BtnEOS, BtnBTC); err != nil {
  return err
}

Here we show users two kinds of BTC and EOS, you can also add more buttons.

APP_CARD

If you think a set of buttons is too monotonous, try APP_CARD, which provides a link to an icon.

card := messenger.AppCard{Title: "CNB", Description: "Chui Niu Bi", Action: "http://www.google.cn",
  IconUrl: "https://images.mixin.one/0sQY63dDMkWTURkJVjowWY6Le4ICjAFuu3ANVyZA4uI3UdkbuOT5fjJUT82ArNYmZvVcxDXyNjxoOv0TAYbQTNKS=s128"}
if err := l.SendAppCard(ctx, msg.ConversationId, msg.UserId, card); err != nil {
  return err
}

Full source code