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Working alone is so exhausting so I created my own assistant

Min on March 15, 2022

Working alone is great... but... I am so tired of dealing with all of these.. these shitty uninspiring, repetitive, tedious tasks... I didn't real...

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lionel-rowe • Mar 15 '22 • Edited

As I understand is what Puppeteer gives me is not an HTML element but something else.. ( is there anybody explain a bit easy for me? i am helpless lol)

The function passed as a callback runs in the context of the headless browser, with all the relevant web APIs available. So within that function, document.querySelector gives a real live DOM element that you can manipulate however you like:

const isItARealDiv = await page.evaluate(() => {
    return document.querySelector("div") instanceof HTMLDivElement
})

isItARealDiv // true

The problem is that when passing the return value back to the parent script, everything is serialized and then deserialized again — something similar to JSON.parse(JSON.serialize(result)). DOM elements can't be properly serialized, getting converted to undefined, so you need to return only the serializable data that you need (text content, specific attributes, inner/outer HTML, etc).

Min • Mar 15 '22

Thank you Lionel-rowe! ( Still confused lol)

Cody Swartz • Mar 17 '22 • Edited

I think Puppeteer and Selenium both suffer from the same problem -- Selenium has been around longer, likely before websites were more complicated with single page magic and dynamic content. The last thing I remembered is that if you query for something before it exists/mounts/renders you'll get nothing back, so you need to wait/poll for it to be available. I thought Puppeteer has helpers around this, or this is why people start to reach for additional libraries on top of these tools to help with this problem. It's been a while since I've touched Puppeteer or Selenium, but I do remember the pains of working with them in single page applications.

Edit: puppeteer.github.io/puppeteer/docs...

lionel-rowe • Mar 17 '22

@ctsstc yeah, Puppeteer gives you various APIs, such as page.waitForSelector, to deal with that, but it can be finnicky knowing exactly what you need to wait for and avoiding race conditons.

lionel-rowe • Mar 15 '22

The parent puppeteer script runs in the Node.JS runtime, whereas the callback to page.evaluate runs in the Chromium browser runtime, headlessly by default ("headless" basically just means that it runs in the background, so you can't visibly see it running). Passing complex data between runtimes is often not possible, because the different runtimes don't know how to interpret it, and DOM elements (DOM is the way the browser interprets HTML) are internally very complex. So to simplify the message passing, Puppeteer uses a serialized format that both runtimes can easily understand. The drawback is that any data that can't be converted to this serialized format is lost.

You can think of "serialized" as meaning something like flat, like a string of letters or binary digits. JSON is a typical serialization format and is useful because it allows the "flattening" of "deep" structures. For example, the JavaScript object { a: { b: 1 } } nests b within a, yet it can be serialized to the JSON string {"a":{"b":1}}. Why is this flat? Well, it's simply the character {, followed by ", followed by a, etc., so it can be read left-to-right; even though the object it represents is a tree structure.

Puppeteer does much of this JSON serialization "under the hood", so you often don't need to worry about it; but JSON can't serialize DOM nodes, because they contain circular structures, e.g. *{ a: { b: *{ a: ... } } } (where * represents a reference to the exact same object). So you need to return only things that JSON can represent — strings, numbers, booleans, null, arrays, and objects containing other JSON-able stuff.

const elementData = await page.evaluate(() => {
    const el = document.querySelector('h1')

    return {
        textContent: el.textContent, // string — OK
        childElementCount: el.childElementCount, // number — OK
        className: el.className, // string — OK
        outerHTML: el.outerHTML, // string — OK
    }
})

console.log(elementData)
// {
//     textContent: 'Posted on Mar 15'
//     childElementCount: 1,
//     className: 'fs-xs color-base-60'
//     outerHTML: '<p class="fs-xs color-base-60">Posted on <time datetime="2022-03-15T02:18:47Z" class="date-no-year" title="Tuesday, March 15, 2022, 2:18:47 AM">Mar 15</time></p>',
// }

Min • Mar 18 '22

Omg @lionelrowe
Big thank you to explain this with full of kind detail!
This is really easy to understand! You are the best!👍👍👍👍👍

Jonathan Haddock • Mar 17 '22

Thanks for sharing this, I've contemplated making an assistant for years. Sure, I could use Google, but something more custom like you've made is more useful I feel. Maybe when I have some free time (!!!) I'll give something similar a go.

Min • Mar 18 '22

haha I tried siri and google assitant. They sucks because there no way to customize.
I am glad to hear you found this is useful. show your progress when you make any progress. I am sure you can make it better one!

JoelBonetR 🥇 • Mar 15 '22 • Edited

Love it 😂 i did a discord weekend project in the past and just for fun and this seems more like a month project.
Did you published it? Can i get a link to include it to my discord server? 🤩

Min • Mar 15 '22

It's not published because I didn't set the notion authentification per user.
it would be so embarrasing if people manage their tasks on my notion. lol

JoelBonetR 🥇 • Mar 16 '22

Hahaha and what about the fun? 😅

Min • Mar 16 '22

I will consider to publish it :)

Akin C. • Mar 16 '22

Hello Min,

thank you for your article.
I've never looked into implementing chatbots, so this is interesting for me.
I like your creative but simple idea of having a digital companion. I don't think that's sad, it's wise, because like you said
"I am so tired of dealing with all of these.. these shitty uninspiring, repetitive, tedious tasks...".

Min • Mar 18 '22

hehe thank you to saying that! Akin!
very glad to hear i inspire somebody with my idea 🥰

🚩 Atul Prajapati 🇮🇳 • Mar 16 '22

Wow my you are the Tony stark

Min • Mar 16 '22

Actually I considered to name it as Jarvis 😂

🚩 Atul Prajapati 🇮🇳 • Mar 17 '22

that's how we inspire

Timmortal • Mar 25 '22

To make a "Jarvis" that follows you from conception to birth and before you merge back in to the universe, is my dream

tq-bit • Mar 16 '22

I love the idea. If you're into shares, you might as well give the Yahoon finance API a shot. It gives you 100 free requests per day, that's more than enough for a single person. For instance, I've built a telegram bot earlier that tells me when is a good time to buy & sell

yahoofinanceapi.com/

Min • Mar 16 '22

Ah-ha! that’s nice idea. Maybe i can add that!

Marissa B • Mar 15 '22

Good job on learning so much new stuff! That was a lot of steps and your story from start to finish was clear. I might have to make one of these.

Min • Mar 15 '22

Really fun project, you should try and let me know your progress!

Tom Smykowski • Mar 17 '22

Congrats on your project. It is extremely epic. Now please monetize it :-)

Min • Mar 18 '22

Thanks for saying it's epic haha

Tom Smykowski • Mar 18 '22

Hobby money Good money :)

Ashwin V • Mar 15 '22

Nice, I learned many terms from this post! Keep going!😊

Min • Mar 15 '22

Thank you! 🥰

Dhravya • Mar 15 '22 • Edited

Damn, this is an amazing project! Great work. Amazing discord bot!

Min • Mar 15 '22

Thank you for saying that🥰

Priyab Dash • Mar 16 '22

Hell I love this idea, now I need to implement it in Python and slack

Min • Mar 18 '22 • Edited

Thank you very much! I want to see your version! please share the progress! 😊

Andras Mihaly • Mar 17 '22

Wow, I really enjoyed reading through your article! Great work on the project, this is pretty impressive! Thanks for sharing @happping_min !

Min • Mar 18 '22

Thank you very much Andras!😊

Dan Walsh • Mar 15 '22

Super impressive feat! It’s one thing to build something new; it’s a whole other thing to learn several libraries/systems in the process. Great work, never stop learning! 😇

Min • Mar 15 '22

hehe thank you very much Dan!

Anneta Wamono • Mar 18 '22

This is a great project! And I've been meaning to make a discord bot and you've really broken the process down quite well.

Min • Mar 18 '22

Haha thanks! Great to hear my article helps others!

Jackson Kasi • Mar 18 '22

wow, that's cool...

Min • Mar 18 '22

Thank you for saying that🥰

SVGator • Mar 15 '22 • Edited

Impressive, to say the least!

Min • Mar 15 '22

Thank you!

Bill Raymond • Mar 17 '22

This was an inspiring and well written article. Thank you!

Min • Mar 17 '22

Thank you very much Bill!

nebocoder • Mar 15 '22

Thank you for this wonderful post. I planned on learning Discord.js to build a personal bot eventually, and I'm so glad I discovered this!

Min • Mar 15 '22

Please show what you make 😀

Fumagalli • Mar 15 '22

This project is incredible!

Min • Mar 15 '22

Thank you for saying that!🤗

Min • Mar 18 '22

Thanks Leonid! Yeah I like what I am doing haha

Brian Kirkpatrick • Mar 20 '22

This is great stuff! I love the way you approached an under-constrained problem and found a value-added approach that contributed real help to your workflow.

One thing I found when going through your steps was, of course, that different developers might want different things from an automated assistant. How did you decide what you wanted an "assistant" to do for you--that is, what were your objectives? Are there specific tedious things you seek to automate for your own workflow versus collaborative tools that support team-based efforts?

Two thumbs up!

Marco Moscatelli • Mar 15 '22

What node js library did you use for NPL?

Min • Mar 15 '22

this!
npmjs.com/package/node-wit

Moses • Mar 19 '22 • Edited

1- great work, you built it using different languages than we did.
2-i see photo of that indian hot chick. dream about it to be your assitant. :)
3- we did it differently, ajax, js, prolog, aiml used in our bot. she has intelligence
check it out in our website. lots of videos there.
4- send me a link to go and talk with her to see how she is doing.
email: support at robot-hosting.com
have a happy time
Moses