background.js

// Function to insert API key into code.
function getApiKey()
{
  return "key"
}



// Listener
//When the Chrome Extension icon is pressed.
chrome.browserAction.onClicked.addListener(function(tab) {
  chrome.storage.sync.get("MicrosoftAPIKey", function(apiKey){
     newKey = ''
      if(apiKey.MicrosoftAPIKey===null){
        var newKey = window.prompt('Please Enter Valid Microsoft Text Analyitics API Key: (https://www.microsoft.com/cognitive-services)');
        if (newKey != '')
        {
          chrome.storage.sync.set({"MicrosoftAPIKey":newKey})
        }
      }
      else{
        newKey = apiKey["MicrosoftAPIKey"];
      }

      //THIS IS TO CHECK IF THE KEY IS VALID. HERE WE SIMPLY RUN AN AJAX CALL AND IF WE GET A RESPONSE WE KNOW THE KEY WORKS. IF NOT WE PROMPT FOR ANOTHER KEY.
      var params ={
        "documents": [{
        "language": "en",
         "id": "1",
         "text": "Test text to see if key works"
        }]};
      $.ajax({
        url: "https://westus.api.cognitive.microsoft.com/text/analytics/v2.0/sentiment?" + $.param( params ),
        beforeSend: function(xhrObj){
        xhrObj.setRequestHeader("Content-Type","application/json");
        xhrObj.setRequestHeader("Ocp-Apim-Subscription-Key",newKey);
        xhrObj.setRequestHeader("Accept","application/json");
        },
        type: "POST",
        data: JSON.stringify(params)
        })
        .done(function(data) {
          chrome.tabs.query({active: true, currentWindow: true}, function(tabs) {
              ensureSendMessage(tabs[0].id, {greeting: "hello"}, newKey);
            })
        }).fail(function(a,b,c){
          var newKey = window.prompt('Please Enter Valid TEXT-ANALYTICS API key (obtained at https://www.microsoft.com/cognitive-services)');
          chrome.storage.sync.set({"MicrosoftAPIKey":newKey})

      })

  });
})

//Sometimes the button may be pressed however application.js script is not ready or already injected into the tab. Therefore here we ping between files to see if everything is ready to send data.
function ensureSendMessage(tabId, message, newKey, callback){
  chrome.tabs.sendMessage(tabId, {ping: true}, function(response){
    if(response) { // Content script ready
      chrome.tabs.sendMessage(tabId, message, function(response){
        if(response["error"]==""){
          makeCall(response['text'], response['parentNode'], response['textHTML'], newKey);
        }
        else {
          alert("Selected text was too long. Please make a smaller selection.")
        }
      });
    } else { // No listener on the other end
      chrome.tabs.executeScript(tabId, {file: "application.js"}, function(){
        if(chrome.runtime.lastError) {
          console.error(chrome.runtime.lastError);
          throw Error("Unable to inject script into tab " + tabId);
        }
        // OK, now it's injected and ready
        chrome.tabs.sendMessage(tabId, message, function(response){
          if(response["error"]==""){
            makeCall(response['text'], response['parentNode'], response['textHTML'], newKey);
          }
          else {
            alert("Selected text was too long. Please make a smaller selection.")
          }
        });
      });
    }
  });
};

//Function that takes the text and formats it and sends off for the AJAX request to microsoft cognitive text API
function makeCall(text, parent, textHTML, newKey){
  var plainText = text;
  var parentNode = parent;
  var textHTML = textHTML;
  var params ={
    "documents": [{
    "language": "en",
     "id": "1",
     "text": plainText
    }]};
  var sentiment_object;
  var keyPhrases_object;
  $.ajax({
    url: "https://westus.api.cognitive.microsoft.com/text/analytics/v2.0/sentiment?" + $.param( params ),
    beforeSend: function(xhrObj){
    // Request headers
    xhrObj.setRequestHeader("Content-Type","application/json");
    xhrObj.setRequestHeader("Ocp-Apim-Subscription-Key",newKey);
    xhrObj.setRequestHeader("Accept","application/json");
    },
    type: "POST",
    // Request body
    data: JSON.stringify(params)
    })
    .done(function(data) {
      //sentiment data being returned here
      //num from 0-1
      sentiment_object = data;
      console.log(data);

  });
  $.ajax({
    url: "https://westus.api.cognitive.microsoft.com/text/analytics/v2.0/keyPhrases?" + $.param( params ),
    beforeSend: function(xhrObj){
    // Request headers
    xhrObj.setRequestHeader("Content-Type","application/json");
    xhrObj.setRequestHeader("Ocp-Apim-Subscription-Key",newKey);
    xhrObj.setRequestHeader("Accept","application/json");
    },
    type: "POST",
    // Request body
    data: JSON.stringify(params)
    })
    .done(function(data) {
      //key phrase data being returned here
      //array of strings
      keyPhrases_object = data;
      console.log(data);
  });
  function waitForElement(){
      if(sentiment_object && keyPhrases_object){
        var message = {sentiment: sentiment_object, keyPhrases: keyPhrases_object, text: plainText, textHTML: textHTML};
        // sends code to create new chrome tab with all information compiled
        createPage(message);
      }
      else{
          setTimeout(function(){
              waitForElement();
          },500);
      }
  }
  waitForElement();
}

function createPage(params)
{
  //Create New Chrome Tab
  chrome.tabs.create({"url": 'response.html'}, function(tab){
    //Wait for tab to be fully loaded before doing anything
    chrome.tabs.onUpdated.addListener(function (tabId, changeInfo, tab) {
      if (changeInfo.status == 'complete') {
          chrome.tabs.query({active: true, currentWindow: true}, function(tabs){
            chrome.tabs.sendMessage(tab.id, params)
          })
        }
      })
    })
}