Использовать API Facebook в веб-приложении Google Apps Script?

#FbLog {
    padding: 10px;
    background-color: white;
    margin-left:auto;
    margin-right:auto;
    cursor: pointer;
}

Код окна OnLoad

Вот код окна window.onload, который я использую для захвата токена Facebook. Это используется только для фиксации токена Facebook, а не для проверки токена. Мое приложение позволяет использовать как логин Facebook, так и обычный логин. Проверка токена Facebook выполняется в другом коде.

window.onload=function(){
  //console.log("This onload did run");

  //get the URL out of the browsers address bar
  //the URL can have multiple different strings attached depending upon the situation.
  //1)Sign in with Facebook. 2) Someone wanting to buy an item 3) Someone wanting to input an item for sale.
  //Any situation other than the FB log in is initiated in the back end.
  window.daURL = window.location;
  window.urlStrng = daURL.toString();

  //console.log("url: " + urlStrng);
  //If there was a FaceBook login, there will be a hashtag in the url string
  window.hashPos = urlStrng.indexOf("#");
  if (window.hashPos > 0) {
    mainStart('InputBlock', 'InputForm');
    window.urlEnd = urlStrng.split("#", 2);
    window.urlTkn = urlEnd[1].split("&", 2);
    window.fbAcsTkn = urlTkn[0].split("=", 2);
    window.finalTkn = fbAcsTkn[1];

    window.scndExpire = urlStrng.substring(urlStrng.indexOf("_in=")+4, urlStrng.length);
    console.log("scndExpire: " + scndExpire);

    google.script.run.withFailureHandler(onFailure)
    .withSuccessHandler(showFBsuccess)
    .processFB_LogIn(window.finalTkn, scndExpire)
  }
  else {
    //If it not a Facebook log in, go to next two choices
    //If the URL string has &L in it, then item listing info is being passed because someone clicked 'Buy'
    window.whatToLoad = urlStrng.indexOf("&L");
    console.log("Second option of onload ran");
    if (window.whatToLoad > 0) {
      google.script.run.withFailureHandler(onFailure)
        .withSuccessHandler(injectBuyForm)
        .include('MutualCmit');
     } else {
     google.script.run.withFailureHandler(onFailure)
       .withSuccessHandler(injectSignInForm)
       .include('SignIn');
     };
  };
};

Обратите внимание, что даже если вход в Facebook активирован в интерфейсе, проверка выполняется в коде .gs. Кто-то может ввести ложный токен Facebook, но он не будет проходить проверку в коде на стороне сервера.

Это код .gs для обработки входа в Facebook:

Проверка кода GS Token GS

//I put this cache line at the very top of the `.gs` file. The other code
// can be put somewhere lower.

var cache = CacheService.getPrivateCache();

function processFB_LogIn(argFB_Tkn, expTime) {
    cache.put('fbTkn', argFB_Tkn, 4000);
    cache.put('fbExpr', expTime, 4000);

    var meFBtkn = cache.get('fbTkn');

    Logger.log("FaceBook Token: " + meFBtkn);

     //This section is for verifying (debug) the user actually signed in through Facebook
    //The first FB token is passed in from the URL right after the user signs in, and when this apps Script loads.
    //IMPORTANT!!!    IMPORTANT!!!   You MUST escape the | character with code %7C

    var AppAccssTkn = 'YourAppID%7YourAppToken'; //This never changes unless app secret changes
    var optnGetTkn = {"method" : "get", "muteHttpExceptions" : true};
      //This 'Debugs' the token returned in the URL after the user signed in with Facebook.  You "should" verify that the token is real.
      var rsltDebug = UrlFetchApp.fetch("https://graph.facebook.com/debug_token?input_token="  + meFBtkn  + "&access_token=" + AppAccssTkn, optnGetTkn);
      var debugTxt = rsltDebug.getContentText();
      Logger.log("debugTxt: " + debugTxt);

      var jsonObj = JSON.parse(debugTxt);
      Logger.log("jsonObj: " + jsonObj);
      //This is the FB user ID
      var useIdTxt = jsonObj.data.user_id;
      cache.put('pubIDcache', useIdTxt, 4000);

      var tknValid = jsonObj.data.is_valid;

      Logger.log("reslt of the debug: " + useIdTxt);
      Logger.log("tknValid: " + tknValid);

      var getFbUseName = UrlFetchApp.fetch("https://graph.facebook.com/" + useIdTxt + "/?fields=first_name&access_token=" + AppAccssTkn, optnGetTkn);

      var objUseName = JSON.parse(getFbUseName);
      var arryFirstName = objUseName.first_name;
      Logger.log("user name: " + arryFirstName);

      cache.put('fbFrstName', arryFirstName, 4000);

   if (tknValid === false) {
     return 'notValid';
   }
   else if (arryFirstName != null) {
     //This is how it determined if someone is logged in or not.
     cache.put('imin', '9847594ujglfugfjogj', 4000);
     return arryFirstName;
  };
};

Вам нужен токен one time App, который не изменится, если вы не измените App Secret. Вы должны сгенерировать это с помощью однократного запуска кода.

Получите токен доступа к приложению с помощью этого кода:

//A Facebook App Token never changes unless you go to the Facebook Developers Console, and you
//change the App Secret.  So, do NOT keep requesting a new App Token.  Just get it once, then
//hard code it into a backend secret function.
// The App Token can be used to modify your App, but you can just do that 'Manually'
function getOneTimeFB_AppToken() {
  Logger.log("getOneTimeFB_AppToken ran");
  //keep this info secret
  //Generate an App Access Token
  var ysshAppID = 'Your App ID';
  var ysshAppSecret = 'Your App Secret';
  var optnAppTkn = {"method" : "get"};
  var getAppTknURL = "https://graph.facebook.com/oauth/access_token?client_id=" + ysshAppID + "&client_secret=" + ysshAppSecret + "&grant_type=client_credentials"
  var getAppTkn = UrlFetchApp.fetch(getAppTknURL, optnAppTkn);
  Logger.log("Object returned from GET: " + getAppTkn)
  var myAppTkn = getAppTkn.getContentText();
  Logger.log("myAppTkn: " + myAppTkn);
};

Опубликовать в Facebook GS Code

function fncPostItemFB(arg1ToPost, arg2ToPost, arg3ToPost, argEtcToPost) {
  var fbCacheTkn = cache.get('fbTkn');
  Logger.log("fbCacheTkn: " + fbCacheTkn);

  if (fbCacheTkn === null) {
    return false;
  };
  Logger.log("fncPostItemFB ran: " + fbCacheTkn);
  return fncPostSecurly_(arg1ToPost, arg2ToPost, arg3ToPost, argEtcToPost);
};

function fncPostSecurly_(arg1ToPost, arg2ToPost, arg3ToPost, argEtcToPost) {
  Logger.log("fncPostSecurly ran");

  var sttsUpdate = argToPost + "your text to post here" + argToPost;
  var fromLogInTkn = cache.get('fbTkn');

  Logger.log("cache FB token: " + fromLogInTkn);

  //This is added security https://developers.facebook.com/docs/graph-api/securing-requests/
  var appsecret_sig = Utilities.computeHmacSha256Signature(fromLogInTkn, "YourAppSecret");
  var optnPostFB = {"method" : "post"};  //
  var PostToFB_URL = "https://graph.facebook.com/FacebookPageOrGroupID/feed?message=" + sttsUpdate + "&access_token=" 
    + fromLogInTkn; // + "&appsecret_proof=" + appsecret_sig;


    //Make a post to the Page
    var whatHappened = UrlFetchApp.fetch(PostToFB_URL, optnPostFB );
    //The return from facebook is an object.  Has to be converted to a string.
    var strFrmFbObj = whatHappened.getContentText();
    Logger.log("Return value of Post: " + strFrmFbObj);

    //When a post is successfully made to Facebook, a return object is passed back with an id value.

    var rtrnVerify = strFrmFbObj.indexOf('{\"id\":\"');
    Logger.log("rtrnVerify: " + rtrnVerify);

    if (rtrnVerify != -1) {
      return true;
    } else {
      return false;
    };
 };

Опубликовать в Facebook Фронтальный Конец Javascript Code

<script>
window.WriteInput = function(whereToPost) {

    window.strngCtgry = document.getElementById('id_Category').value;
    window.strngMaker = document.getElementById('id_Maker').value;
    window.strngAskingPrice = document.getElementById('id_AskingPrice').value;
    window.strngType = document.getElementById('id_ShrtDesc').value;
    window.strngFunction = document.getElementById('id_Function').value;
    window.strngCosmetic = document.getElementById('id_Cosmetic').value;  
    window.strngDescription = document.getElementById('id_Description').value;
    window.strngUserID = document.getElementById('pubID_Holder').textContent;
    window.addrIP = document.getElementById('IP_Holder').textContent;

  if (whereToPost === 'fb') {
    console.log("fncPostToFB ran" + strngDescription);
    if (strngDescription === "" || strngAskingPrice === "") {alert("Missing Input"); return false;};
    google.script.run.withFailureHandler(postFbFail)
    .withSuccessHandler(savedToFB)
    .fncPostItemFB(strngCtgry, strngMaker, strngAskingPrice, strngType, strngDescription, strngFunction, strngCosmetic, addrIP);
  } else {
    google.script.run.withFailureHandler(onFailure)
      .withSuccessHandler(savedLst)
      .fncSaveItem(strngCtgry, strngMaker, strngAskingPrice, strngType, strngDescription, strngFunction, strngCosmetic, addrIP);
      };
    };

window.savedLst = function(rtrnInput) {
   if (rtrnInput === false) {
     alert("Failed to Save Data");
   }
   else if (rtrnInput === "NotLogged") {
     alert("You are not logged in!");
     mainStart('SignInBody', 'SignIn');
   }
   else if (rtrnInput === "noItemForPic") {
     alert("You Need to Save an Item to attach the Picture to");
   }
   else {
  alert("Your Data Was Saved!");
  //Show the listing that was just saved next to the upload Pics button
  document.getElementById('listToPic').innerHTML = document.getElementById('id_ShrtDesc').value +
    ", " + document.getElementById('id_Description').value +
    ", - Made By: " + document.getElementById('id_Maker').value +
    ", Price: $" + document.getElementById('id_AskingPrice').value;

    };
};

window.postFbFail = function() {
  alert("Failed to Post to Facebook!  Try Signing In Again.");
  unsignFB();
};

window.savedToFB = function(pstFbStat) {
  if (pstFbStat === false) {
    alert("You are Not Signed in to Facebook!");
    unsignFB();
    google.script.run.withFailureHandler(onFailure)
      .signOutFB();
  } else {
    alert("Your Item was Posted to Facebook!");
  };
};

</script>