(1) Create a configuration module in your nodejs project with the following settings:

var config = {
   individualCustomerurl: "https://<host_name>/sap/c4c/odata/v1/c4codata/IndividualCustomerCollection/".credential: "<your user name>:<your password>".accessToken: "access token of your test subscription account"
};
module.exports = config;
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You must maintain a valid user name and password which could have access to create new individual customer in your C4C system.

The access token will be used when you try to send a message to an user who has subscribed your Wechat account via Wechat Restful API. It will expire by default 2 hours after generation. The token could be refreshed based on appid and secret. For simplification purpose I just generate the token and store it in configuration file.

(2) Once a Wechat user presses “subscribe” button, an event with HTTP post will be sent to the Wechat server which is bound to your subscription account. As a result we have to react to this post request, parse the Wechat ID which has clicked the “subscribe” button, and create a new individual customer in C4C system based on this Wechat ID.

Here below is the source code how we react to the event with event key “subscribe”.

(1) the welcome message “Welcome to Jerry’s subscription account” is hard coded;

(2) The Wechat ID of user who has finished subscription is stored in variable fromUserName

var request = require('request');
var createAccount = require(".. /service/createAccountInC4C.js");
var getXMLNodeValue = require(".. /tool/xmlparse.js");
var formattedValue = require(".. /tool/formatValue.js");
var replyMessage = require(".. /tool/replyMessage.js");

module.exports = function (app) {
  app.route('/').post(function(req,res){
    var _da;
    req.on("data".function(data){
        _da = data.toString("utf-8");
    });
    req.on("end".function(){
        console.log("new http post: " + _da);
        var msgType = formattedValue(getXMLNodeValue('MsgType',_da));
        if( msgType === "event") {var event = formattedValue(getXMLNodeValue('Event',_da));
          if( event === "subscribe") {var replyxml = replyMessage(_da, "Welcome to Jerry's subscription account");
            var fromUserName = formattedValue(getXMLNodeValue('FromUserName',_da)); createAccount(fromUserName); res.send(replyxml); }}}); }); };Copy the code

(3) The individual customer is created by C4C OData service implemented in module createAccountInC4C.js.

var config = require(".. /.. /config.js");
var request = require('request');
var postWCMessage = require("./postMessageToUser.js");

var getTokenOptions = {
        url: config.individualCustomerurl,
        method: "GET".json:true.headers: {
            "content-type": "application/json".'Authorization': 'Basic ' + new Buffer(config.credential).toString('base64'),
            "x-csrf-token" :"fetch"}};function getToken() {
  return new Promise(function(resolve,reject){
      var requestC = request.defaults({jar: true});
      requestC(getTokenOptions,function(error,response,body){
       var csrfToken = response.headers['x-csrf-token'];
       if(! csrfToken){ reject({message:"token fetch error"});
          return;
       }
       resolve(csrfToken);
      }); // end of requestC
     });
}

function _createIndividualCustomer(token, fromUserName){
	return new Promise(function(resolve, reject){
		var oPostData = {
			"FirstName":"Wechat"."LastName":fromUserName,
 		"RoleCode": "ZCRM01"."CountryCode": "US"."StatusCode": "2"
		};
		var requestC = request.defaults({jar: true});
        var createOptions = {
              url: config.individualCustomerurl,
              method: "POST".json:true.headers: {
                  "content-type": "application/json".'x-csrf-token': token
              },
              body:oPostData
        };
        
        requestC(createOptions,function(error,response,data){
            if(error){
                reject(error.message);
            }else{ resolve(data); }});// end of requestC
	});
}

module.exports = function createAccount(fromUserName){
  getToken().then(function(token) {
  console.log("token received: " + token);
  _createIndividualCustomer(token, fromUserName).then(function(data){
    var message = "account created: " + data.d.results.CustomerID;
    console.log(message);
    postWCMessage(fromUserName, message);
  });
});
};
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In the code the first name of created account is hard code as Wechat and the last name is filled with variable fromUserName parsed from previous step.

(4) Once individual customer is created in C4C system successfully, a responsible message will be sent to Wechat subscription account user to notify him/her with the ID of created account.

This reply is implemented by Wechat message Restful API:

var config = require(".. /.. /config.js");
var request = require("request");

function printObject(oData){
	for( var a in oData){
		console.log("key: " + a);
		console.log("value: " + oData[a]);
		if( typeof oData[a] === "object"){ printObject(oData[a]); }}}function sendWCMeaasge(toUser,sMessage){
	console.log("begin to send message to user: " + toUser + " with message: " + sMessage);
    var options = {
            url:"https://api.weixin.qq.com/cgi-bin/message/custom/send?access_token=" +
            config.accessToken, 
            method: "POST".json:true.headers: {
            	"content-type": "application/json"},
            body: {"touser":toUser,
              "msgtype":"text"."text":
              {
                   "content":sMessage
              }
                }
          };
      request(options,function(error,response,data){
        console.log("Status message: " + response.statusMessage);
        console.log("Data: " + data.errmsg);
      });
  }

module.exports = sendWCMeaasge;
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It is very convenient to use this Restful API to send message to a given Wechat user who has subscribed the testing account. You could test it in postman:

For more of Jerry’s original articles, please follow the public account “Wang Zixi “: