================================ Spring Social Wechat===============================

This is a Spring Social based java SDK for Wechat official account development.

Usgae

1 Create an official account in Wechat web site, and then take a note on below parameters

AppID
AppSecret
Token

2 Create a Spring Web MVC Controller

@Controller
@RequestMapping("/wechat")
public class WechatController
{
    private static final Logger logger = Logger.getLogger(WechatController.class);

    @Value("${social.wechat.Token}")
    private String wechatToken;

    // Verify HTTP message are from Wechat server
    @RequestMapping(method = RequestMethod.GET)
    @ResponseBody
    public String validate(@RequestParam(value = "signature", required = true) String signature,
            @RequestParam(value = "timestamp", required = true) String timestamp,
            @RequestParam(value = "nonce", required = true) String nonce,
            @RequestParam(value = "echostr", required = true) String echostr)
    {
        String response = "";
        if (Signature.check(signature, wechatToken, timestamp, nonce))
        {
            if (echostr != null && !echostr.equals(""))
            {
                response = echostr;
            }
        }
        else
        {
            response = "Failed to validate request!";
            logger.info(response);
        }

        return response;
    }

    // Handle Wechat message from end user
    @RequestMapping(method = RequestMethod.POST)
    @ResponseBody
    public String process(HttpServletRequest request)
    {
        String response = "";

        String signature = request.getParameter("signature");
        String timestamp = request.getParameter("timestamp");
        String nonce = request.getParameter("nonce");

        if (!Signature.check(signature, wechatToken, timestamp, nonce))
        {
            response = "Failed to validate request!";
            logger.info(response);
        }
        else
        {
            response = process(MessageFactory.create(request));
        }

        return response;
    }
}

3 Handle business logical

public String process(Message message) 
{
    if (message.getType() == MessageType.event)
    {
       ....
    }
    else if (message.getType() == MessageType.text)
    {
        TextMessage receivedMessage = (TextMessage) message;
        TextMessage responseMessage = new TextMessage();

        responseMessage.setToUserName(receivedMessage.getFromUserName());
        responseMessage.setFromUserName(receivedMessage.getToUserName());

        responseMessage.setContent(String.format(
            "Hello, %s, welcome to Spring Social Wechat.",
            receivedMessage.getFromUserName()));

        return responseMessage.toXmlString();
    }
    else
    {
        ...
    }
}

4 Create a WeChat instance to invoke advance feature provided by wechat.

Except passive response message, Wechat platform provides a lot of advanced interface for official account development, but all of them needs an access token. To gain the access token and utilise these advance interface, we need to create a WeChat instance first.

WechatServiceProvider provider = new WechatServiceProvider(appid, secret);
AccessGrant accessGrant = provider.getOAuthOperations().authenticateClient(null);
Wechat wechat = provider.getApi(accessGrant.getAccessToken());

5 Send customer service message

TBD.

6 Send group message

TBD.

7 Send template message

Define template message

public class BalanceNotification
{
    private ValueColorPair first;
    private ValueColorPair greeting;
    private ValueColorPair date;
    private ValueColorPair balance;
    private ValueColorPair remark;

    public ValueColorPair getFirst()
    {
        return first;
    }

    public void setFirst(ValueColorPair first)
    {
        this.first = first;
    }

    public ValueColorPair getGreeting()
    {
        return greeting;
    }

    public void setGreeting(ValueColorPair greeting)
    {
        this.greeting = greeting;
    }

    public ValueColorPair getRemark()
    {
        return remark;
    }

    public void setRemark(ValueColorPair remark)
    {
        this.remark = remark;
    }

    public ValueColorPair getDate()
    {
        return date;
    }

    public void setDate(ValueColorPair date)
    {
        this.date = date;
    }

    public ValueColorPair getBalance()
    {
        return balance;
    }

    public void setBalance(ValueColorPair balance)
    {
        this.balance = balance;
    }
}

public void send(Calendar today, SimpleDateFormat format, String touser, String screenName)
{
    BalanceNotification balanceNotification = new BalanceNotification();
    balanceNotification.setFirst(new ValueColorPair(String.format("Dear %s,", screenName), null));
    balanceNotification.setGreeting(new ValueColorPair(String.format("Portfolio balance for %s",
            "Edward"), null));
    balanceNotification.setDate(new ValueColorPair(format.format(today.getTime()), null));
    balanceNotification.setBalance(new ValueColorPair("+0.50", Color.Green));

    TemplateMessage<BalanceNotification> message = new TemplateMessage<BalanceNotification>();
    message.setTouser(touser);
    message.setTemplateId("xxxxxxxxxx");
    message.setData(balanceNotification);

    wechat.messageOperations().send(message);
}