AutoHotkey Webinar- Intro to Web Scraping

In this AutoHotkey Webinar we cover an Intro to Web Scraping.Intro to Web Scraping

Video Hour 1: High-level:

  • What is an API call
  • Web Scraping vs. WebServices / API
  • Document Object Model (DOM)
  • Structure of a web page
  • Frequently used Methods & properties

Video Hour 2: Coding and Q&A

  • Building code
  • Using AutoHotkey syntax writer
  • IE verse Edge
  • Selenium for Chrome, Firefox, IE , etc.

Script Highlight: Long-pressing Hotkey to Exit a script

The below script is more of an example of how you can have more than one hotkey for a given key by tying it to how long you press the key.  In the below script, if you hold down Escape longer than 1/2 a second it will close the active program.

 

PowerPoint Deck presented in Intro to Web Scraping

Q) What is an API? (Application Programming Interface?)

A) Basically it is how devices (computers, tablets, phones, servers, etc) talk to each other.

Q) What are examples of common API calls

A) Below are a list of some examples (but the list is limitless)

  • Web Browser pulling up products on Amazon.com
  • Application / Software querying products for sale on Amazon.com
  • App on your phone getting latest Weather
  • Database pulling updated sales report
  • Using your Tablet to Select movies to watch on Netflix
  • DropBox application syncing files between your computer & cloud
  • Using Web browser to access files in DropBox

Q) What are the Main Differences between Webservice / API call & Web Browser

Q) What is the HTML DOM: Document Object Model

A) Think of the DOM as the “road map” for a webpage.  Depending on what you are trying to get/set, you’ll rely on the DOM to get the exact element you’re looking for.   Below is an image which stresses the more-frequently-used parts.

Q) How does a Family Tree similar to the DOM?

A) Both are “hierarchical” and, depending on what elements are populated, you can reliably “talk” to the correct node.  The first tree below shows how some nodes have all elements populated while some are missing some (like Name and ID)

Q) What happens if a new Node is inserted in the Tree?

A) It depends on which element you are looking at.  Names and IDs probably will not change however Tagnames often will.  This is why it is recommended to first use IDs, then Names, then ClassNames.  Use Tagname last (or go up the tree a bit and grab an ID/Name then use that “branch”)

Q) What are the frequently used methods for selecting an Element?

A) The methods below are sorted by the most reliable/stable (not presence).  When ID is present- use it!  If no ID, Name is another great one…  Classname is also becoming more reliable

  1. getElementByID– Great because if it is present it is should always unique
  2. getElementsByName– While not required to be unique, it often is so very reliable
  3. getElementsByClassName– Often unique and present
  4. getElementsByTagName– Check if there is an ID/name above it, then jump “down” to it first then use TagName)
  5. querySelector/querySelectorAll- Most flexible but is the most complicated- (If you know CSS, this is much not hard to adapt)

Q) What are Frequently used Get/Set/Trigger HTML Elements?

A) The below are the most frequently used however this is highly tied to what your goal is.

Methods:
.click() – Clicks the element
.fireEvent(“onclick”) – Fires the click event (sometimes needed to trigger the event)
.focus() – Place the cursor in the element/edit field (set cursor)
.selectedIndex() – Dropdown box selection
.checked() – Radio / Checkbox selection

Properties (Get & Set):
innerText – the plain-text for the element
.value – the plain-text for the element
.outerHTML – the HTML for the element

Additional Resources

AHK specific:

Learning the DOM (If you spend time on this you’ll thank us later!):

AutoHotkey Webinar- Working session demonstrating ways to automate programs

AutoHotkey webinar– Working Session

This webinar was mostly working sessions and not a lot of resources.  It is a follow-up to our last webinar which discussed many different ways to automate windows programs using AutoHotkey.  Please the resources on this page, and watch the videos, if you want to review in depth.  We had links to the various tools that were used in the below webinar.

Script highlight: Use Google to Search for help

Thanks for attending the AutoHotkey webinar!  If you’re not currently registered for future ones, you can do so here

AutoHotkey Webinar- Various ways to use AHK to automate tasks in Windows

In the first hour of our March AutoHotkey webinar we covered core concepts of what to consider when writing a script.AutoHotkey webinar

The second hour we took a deeper dive into coding using some of the methods mentioned in hour one.

Content & Resources shared in AutoHotkey webinar

Script highlight:  Copy Explorer path to clipboard

Things to Consider when writing a NEW script

  1. Are you behind a time-crunch to get the job done?
  2. Are you looking for a 1-time solution?
    1. What are the odds that you could re-purpose your solution for something else at a later date?
  3. Will this be run on multiple:
    1. Computers
    2. Windows versions
    3. Users
    4. What software is also running on computers
    5. Bitness (32 & 64) of OS, AutoHotkey , program interacting with
  4. Is there existing code that you can borrow / steal / leverage?
    1. Previous code I’ve written
    2. Sites like:  AHK Forum  Stack Overflow  Reddit  Github  the-Automator  JSZApp  Jack Dunning Blog
    3. Ask colleagues / friends / Social channels
      1. AHK Forum   StackOverflow    Reddit
      2. LinkedIn 1  LinkedIn 2
      3. Facebook 1  Facebook2  Facebook 3
      4. Joe Glines  Jackie Sztuk  Hellbent  ahkTuts AboutScript  Chunjee  AHK vids
  5. Will someone other than you be using / maintain the code? Program to their “level”

Many ways to “Control / Interact” Window’s programs

Example Scripts used during Coding demonstration of AutoHotkey webinar

AHK Webinar- Simple and Associative Arrays in AutoHotkey

We had a great webinar on Arrays!  Here are links to the videosSimple and Associative Arrays in AutoHotkey

  • First hour video discussing below points
  • Second hour where we took a deep dive trouble-shooting an attendee’s script

Benefits of Simple and Associative Arrays in AutoHotkey

  • Speed – Objects are very fast!
  • Code maintenance / easier to update
  • Structured data
  • Easier to read / understand
    • Dot notation (names) can be very easy to read
    • Automatically group “variables” in a meaningful structure / Nesting deeper levels
  • Built-in functionality
  • Iterating over keys / values
  • Insert / Append to last
  • Remove / Remove last item
  • Count (Length)
  • Set / assign value (Index/Key – Value pair)
  • Retrieve / Lookup (Index/Key – Value pair)

Things to Remember with Simple and Associative Arrays in AutoHotkey

  • Keys are not case sensitive The following results in one key-value pair: {ex:1,EX:2}
  • Keys are unique (If you have duplicates, only the last one will be kept)
  • Simple Arrays can not have “empty” spots
  • Associative Arrays are not, necessarily, ordered in the way you’d expect (when iterate over can seem out of order)
  • Simple arrays are sequential
  • Simple Arrays can be considered Associative Arrays where the Index is the key
  • You must declare the object before or during population
  • To “nest” an object, you must declare the Parent and sub-objects first too!
  • Although the same, Lexikos recommends using { } for Associative Array & [ ] for Simple Array
  • You do not need to save the object to iterate over it
  • Arrays are often returned from API calls in JSON
  • While Simple and Associative Arrays in AutoHotkey take a bit of getting used to, in the long run, they are great time savers!

Resources for learning Simple and Associative Arrays in AutoHotkey

Featured script

Pasting clipboard to p.ahkscript.org– great for collaborating with others!

Additional Resources

During the webinar a few other scripts were mentioned.  Here are the links that were shared: