Initial commit

Author: lbell

.gitignore

@@ -0,0 +1 @@
+.vscode/

manifest.json

@@ -0,0 +1,14 @@
+{
+  "manifest_version": 2,
+
+  "name": "Orpets",
+  "version": "0.1.1",
+  "description": "Easily see if Fido can stay at your Orbitz.com(R) Hotel",
+  "permissions": ["storage"],
+  "content_scripts": [
+    {
+      "js": ["orpets.js"],
+      "matches": ["https://www.orbitz.com/Hotel-Search*"]
+    }
+  ]
+}

orpets.js

@@ -0,0 +1,195 @@
+const storageHours = 48;
+var processedNodes = [];
+const listings = document.getElementsByClassName("listing");
+
+clearLocalStorage();
+window.onload = doOnScroll;
+window.onscroll = doOnScroll;
+
+/**
+ * Fires on scroll
+ */
+async function doOnScroll() {
+  for (var i = listings.length - 1; i >= 0; i--) {
+    // for (var i = 1; i >= 0; i--) {
+    var listing = listings[i];
+
+    if (processedNodes.includes(listing) === false) {
+      if (isScrolledIntoView(listing) === true) {
+        processedNodes.push(listing);
+
+        let listUrl = getLink(listing);
+
+        let petText = await getPetText(listUrl);
+
+        appendPetText(listing, petText);
+      }
+    }
+  }
+}
+
+/**
+ * Determines whether given element is visible in the viewscreen
+ *
+ * @param {element} el DOM Element
+ * @returns bool
+ */
+function isScrolledIntoView(el) {
+  let elTop = el.getBoundingClientRect().top;
+  let elBottom = el.getBoundingClientRect().bottom;
+
+  let isVisible = elTop >= 0 && elBottom <= window.innerHeight;
+
+  return isVisible;
+}
+
+/**
+ * Pauses code execution for desired amount.
+ *
+ * @param {int} milliseconds Time to wait
+ * @returns promise
+ */
+function sleep(milliseconds) {
+  return new Promise((resolve) => setTimeout(resolve, milliseconds));
+}
+
+/**
+ * Get the link from listing element
+ *
+ * @param {html} listing
+ * @returns string
+ */
+function getLink(listing) {
+  const listingLink = listing.getElementsByClassName("listing__link");
+  const href = listingLink[0].href;
+  const baseURL = href.substring(0, href.indexOf("?"));
+  return baseURL;
+}
+
+/**
+ * Get the Pet Text for a given url
+ * Checks local storage first, and if not found, fetches the text from the given
+ * URL and stores it for the future.
+ *
+ * @param {string} url
+ * @returns string
+ */
+async function getPetText(url) {
+  let petText = getWithExpiry(url);
+
+  if (petText !== null) {
+    return petText;
+  } else {
+    let expires = storageHours * 60 * 60 * 1000;
+
+    petText = await scrapePetText(url);
+
+    setWithExpiry(url, petText, expires);
+
+    return petText;
+  }
+}
+
+/**
+ * Sets a localstorage item with expiration date
+ *
+ * @param {string} key Key name
+ * @param {string} value Value content
+ * @param {int} exp Expiration time (in milliseconds)
+ */
+function setWithExpiry(key, value, exp) {
+  const now = new Date().getTime();
+
+  const item = {
+    origin: "orpets",
+    value: value,
+    expiry: now + exp,
+  };
+  localStorage.setItem(key, JSON.stringify(item));
+}
+
+/**
+ * Get the Pet Text from local storage and check whether it has expired. Deletes
+ * the key/value if expired and returns null instead.
+ *
+ * @param {string} key Key to search for
+ * @returns Value or Null
+ */
+function getWithExpiry(key) {
+  const value = localStorage.getItem(key);
+
+  if (!value) {
+    return null;
+  }
+
+  const item = JSON.parse(value);
+  const now = new Date().getTime();
+
+  if (now > item.expiry) {
+    localStorage.removeItem(key);
+    return null;
+  }
+  return item.value;
+}
+
+/**
+ *
+ * @param {string} url URL of hotel general info to scrape
+ * @returns {string} Pet text in <li> form
+ */
+async function scrapePetText(url) {
+  console.log("Scraping"); // DEBUG
+
+  // Limit the rate of hits to be polite.
+  await sleep(Math.random() * 3000 + 1000); // wait 1 to 3 seconds
+
+  let response = await fetch(url);
+
+  if (!response.ok) {
+    throw new Error(`HTTP error! status: ${response.status}`);
+  }
+
+  var parsedResponse = new window.DOMParser().parseFromString(await response.text(), "text/html");
+
+  var petText = parsedResponse.querySelector("[itemprop=petsAllowed]").innerHTML;
+
+  return petText;
+}
+
+/**
+ *
+ * @param {element} listing HTML Element
+ * @param {string} petText <li> listings of pet text info
+ */
+function appendPetText(listing, petText) {
+  const petContent = document.createElement("ul");
+  petContent.innerHTML = petText;
+  listing.appendChild(petContent);
+}
+
+/**
+ * Houseclaning function to clear all Orpets data that is expired on each load
+ */
+function clearLocalStorage() {
+  const now = new Date().getTime();
+
+  for (let i = 0; i < localStorage.length; i++) {
+    const key = localStorage.key(i);
+
+    let item;
+    try {
+      item = JSON.parse(localStorage.getItem(key));
+    } catch (e) {
+      item = {};
+    }
+
+    if (item.origin === "orpets" && item.exipiry < now) {
+      localStorage.removeItem(key);
+    }
+
+    // Nuclear Option
+    // if (item.origin === "orpets") {
+    //   localStorage.removeItem(key);
+    // }
+  }
+}