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I am trying to solve an issue with the format of documents in a MongoDB depicted below.

{
  "_id": {
    "$oid": "68dc4f78e11553b3647231e2"
  },
  "name": "Dutch Bros",
  "address": "25 Down Street, Salt Lake City, UT",
  "facilities": [
    "Hot drinks",
    "Food"
  ],
  "coords": [
    -0.9690884,
    51.455041
  ],
  "reviews": [
    {
      "author": "John Smith",
      "rating": {
        "$numberDecimal": "5"
      },
      "createdOn": {
        "$date": "2025-09-30T06:00:00.000Z"
      },
      "reviewText": "Great Place. Would come back again!"
    },
    {
      "author": "Jane Doe",
      "rating": {
        "$numberDecimal": "4"
      },
      "createdOn": {
        "$date": "2025-09-30T06:00:00.000Z"
      },
      "reviewText": "Okay Place. Would come back again!"
    }
  ]
}

My goal is to match review sub-document(s) based on an attribute it has such as ratings being equal to five. I know that I could take the reviews array as a whole and iterate over them to search the attributes for what I need, but I want to be able to find it directly in the MongoDB query so the MongoDB server does the work while it saves my express server any additional workload.

I guess what I am asking is how do I reference the iterable objects in the reviews array. I hope that was clear enough and I apologize if it wasn’t!

I’ve successfully implemented a version that iterates in a for loop on the express server in the controller, but this is what I want to avoid. I’ve also tried using a .get() method on the returned array because I saw that it was an available method for the object, but that yielded an error. I’ve also tried to build a query which was close to what I believe the solution is going to be but I can’t understand how MongoDB element matches an array item, see below for my failed attempt.

const monReview = await Loc
            .findById(req.params.locationid)
            .select('name reviews')
            .where('reviews')
            .elemMatch({$eq: req.params.reviewRating})
            .exec();  

Here is some infromation about shippingratechange for Stripe express checkout.
https://docs.stripe.com/js/elements_object/express_checkout_element_shippingratechange_event

which implemented and when the Stripe payment button is clicked the modal window properly displayed:

Then, as you see on the image, there are several shipping options properly passed and rendered. Once another shipping option (with another price) is chosen, it triggers ‘shippingratechange’. How to update the Total because the shipping price was changed?

When I change the shipping option, it changes fine, but the Total remains unchanged, although shippingratechange gets triggered with no questions. How to set another totals value, for example 99.90 (let’s say the math calculated).

What should be added to here?

expressCheckoutElement.on('shippingratechange', function(event) {
  var resolve = event.resolve;
  var shippingRate = event.shippingRate;
  // handle shippingratechange event

  // define payload and pass it into resolve
  var payload = {
    shippingRates: [
      shippingRate
    ]
  };

  // call event.resolve within 20 seconds
  resolve(payload);
});

I have a React app deployed on AWS S3 + CloudFront.

One of my routes uses a dynamic import (import()), and the corresponding JS chunk is very small (~3.7 KB).

On the first load, the request for this file takes about 650 ms, but if I refresh the page immediately afterward, it only takes about 45 ms.

Here’s the request and response details from Chrome DevTools for the file:

Request URL: https://admin.simprosysapis.com/assets/RolesList-DVgRFD0k.js
Request Method: GET
Status Code: 200 OK
Remote Address: 18.66.57.77:443
Referrer Policy: strict-origin-when-cross-origin

Response headers

cache-control: max-age=3600, must-revalidate
content-encoding: br
content-type: text/javascript
server: SimprosysAPI
via: 1.1 ...cloudfront.net (CloudFront)
x-cache: Miss from cloudfront

Request headers

accept-encoding: gzip, deflate, br, zstd
cache-control: no-cache
pragma: no-cache
user-agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) ...

---

My questions

1. Why does a 3.7 KB file take ~650 ms to load the first time?

   • Is this mostly TLS/handshake + CloudFront latency rather than file size?
   • Is the x-cache: Miss from cloudfront header responsible?

2. Why does it become so much faster (~45 ms) on refresh?

   • Is the browser using disk/memory cache or a CloudFront cached copy?

3. Is there a way to improve the first load time for these small dynamic chunks (e.g., preloading, prefetching, or CloudFront settings)?

---

What I tried

• Checked headers: content-encoding: br confirms compression is working.
• Cache headers look reasonable (max-age=3600).
• Behavior is consistent across multiple builds.

---

Expected / Desired

I want to understand if this latency difference is normal for CloudFront + S3 dynamic imports, and whether I can optimize the first-load latency further.

I’m trying to replicate a hero section design where the gallery card looks like it is carved into the main image container (instead of floating on top).

I attempted using an SVG clipPath with an organic shape applied to the .main-image, but the gallery card still appears as a separate overlay. It doesn’t blend with the container as expected.

<div class="organic-gallery">
  <!-- Clip path definition -->
  <svg width="0" height="0">
    <defs>
      <clipPath id="organic-carved-shape" clipPathUnits="objectBoundingBox">
        <path d="M 0.06,0 L 0.94,0 C 0.97,0 1,0.03 1,0.06 L 1,0.94 C 1,0.97 0.97,1 0.94,1 L 0.7,1 C 0.68,1 0.66,0.998 0.64,0.995 L 0.05,0.82 C 0.02,0.815 0,0.8 0,0.78 L 0,0.06 C 0,0.03 0.03,0 0.06,0 Z" />
      </clipPath>
    </defs>
  </svg>

  <div class="gallery-container">
    <!-- Main image background -->
    <div class="main-image">
      <img src="circuit.jpg" class="circuit-bg" />
      
      <!-- floating labels -->
      <div class="feature-label" style="top: 3rem; right: 3rem;">On-Device Analysis</div>
      <div class="feature-label" style="top: 8rem; right: 6rem;">Smart App</div>
    </div>

    <!-- supposed to be carved into the main container -->
    <div class="gallery-card">
      <div class="gallery-images">
        <div class="gallery-item">Thumb 1</div>
        <div class="gallery-item">Thumb 2</div>
      </div>
    </div>
  </div>
</div>

.gallery-container {
  position: relative;
  height: 600px;
}

.main-image {
  position: absolute;
  inset: 0;
  border-radius: 3rem;
  overflow: hidden;
  clip-path: url(#organic-carved-shape);
}

.circuit-bg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.gallery-card {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 380px;
  padding: 1.5rem;
  border-radius: 2rem;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

Current result:
The gallery card simply overlaps the main image.

Expected result:
The gallery card should appear as if it’s part of (or cut into) the main container — following the same organic shape, not just sitting on top.

Question:
What’s the correct way (CSS clip-path, mask, pseudo-elements, or another technique) to make the gallery card look “carved into” the image container?

Achieving clear lines in HTML canvas requires setting the CSS canvas height and width to be the canvas height and width / device pixel ratio:

this.element.style.height = this.element.height / dpr + "px";
this.element.style.height = this.element.height / dpr + "px";

An unfortunate outcome of this is that the lineTo command will now be incorrect. For example, if I draw a square as:

ctx.lineTo(113.395,54.233);
ctx.lineTo(120.791,54.233);
ctx.stroke();

ctx.lineTo(120.791,54.233);
ctx.lineTo(120.791,46.837);
ctx.stroke();

ctx.lineTo(120.791,46.837);
ctx.lineTo(113.395,46.837);
ctx.stroke();

ctx.lineTo(113.395,46.837);
ctx.lineTo(113.395,54.233);
ctx.stroke();

The result is not square:

Anti-aliasing aside, if we average the placement of each line to its darker side, the width is approximately 7px (correct), while the height is approximately 8px (incorrect).

Does anyone have a solution for this?

I want to use the directory- and file-reading functions from 'node:fs' to merge multiple files into one file. For example, I have the following script:

import fs from 'node:fs';
import { readdir, readFile, stat } from 'node:fs/promises';
import { join } from 'node:path';
var myStream = fs.createWriteStream('path/to/output.txt', {flags: 'a'});
var dirPath = 'path/to/mydirectory';
try {
    const entries = await readdir(dirPath, { recursive: true, withFileTypes: true });
    for (const entry of entries) {
        if (entry.isFile()) {
        const myPath = join(entry.parentPath, entry.name);
        const { size } = await stat(myPath);
        const contents = await readFile(myPath);
        myStream.write('<path>' + myPath + '</path>' + '<size>' + size.toString(10) + '</size>n' + contents + 'n');
     }
};
} catch (err) {
    console.error(err);
}; 
myStream.end()

My question is: what will happen if a directory cannot be opened or some part of a file cannot be read (due to bad/problematic sectors on disk, corrupted file system, etc.)? Will the program just freeze, so I will need to terminate it manually? Or only the corresponding file/directory will be skipped? Will the program skip a file in its entirety or only the unreadable part of it? What type of error, if any, will the program report? I have not found any information on this topic. Would it be possible to use Node.js to make the full list of problematic directories and files that are located in a given directory?

I’m building a multi-step form in React where users can upload photos along with other inputs.

Currently:

I store all the form values in a formData state object.

To persist progress across refreshes, I save formData in localStorage.

Problem:

Uploaded photos are stored using URL.createObjectURL(file).

These object URLs don’t survive a page refresh, so the images are lost even though the rest of the form data is restored from localStorage.

Question:

Is there a way to persist uploaded photos across page refreshes without just dumping everything into localStorage?

What are the common patterns for handling this in React multi-step forms?

Should I use IndexedDB for files?

Should I upload files immediately to a temporary backend storage (and store only the reference in localStorage)?

Or is there another best practice for this use case?

How to find and connect a fast API for a TikTok video downloading website that downloads tiktok videos without watermark, in full quality.

I tried to make a website that asks for the tiktok video link and provide the video in full quality without watermark.

I saw this tutorial that teaches how to do complex multilayer parallax scrolls and implemented on my website. While prototyping I found some weird lines that would appear while manipulating the PNG’s (I know the file size is big, I will fix it later). I thought it could be just some white pixels that just needed to be cleaned, but after cleaning all edges the problem persisted. Any idea why browsers are with this render issue?

https://codepen.io/Ramoses-Hofmeister-Ferreira/pen/wBMWBvZ

I was trying to manipulate some images inside an SVG so I could have a responsive multilayer parallax scroll, yet browsers are rendering strange white lines on the edge of the PNG’s that are inside of the SVG.

HTML:

<body>
    <div class="banner">
        <div id="mountain"></div>
    </div>
</body>

CSS:

body {
    margin: 0;
    background-color: #000000;
}

#mountain {
    width: 100%;
    height: 100vh;
    overflow: hidden;
}

#mountain svg {
    width: 100%;
    height: 100%;
    object-position: center;
}

JS:

function loadSVG() {
    fetch("https://raw.githubusercontent.com/astronaut954/pedro/main/img/parallax_scroll.svg")
        .then(res => res.text())
        .then(svg => {
            const mountain = document.getElementById("mountain");
            mountain.innerHTML = svg;

            const svgEl = mountain.querySelector("svg");
            svgEl.setAttribute("preserveAspectRatio", "xMidYMid slice");

            createWrapper("#layer_1");
            createWrapper("#layer_2");

            setAnimationScroll();
            setCloudAnimation();

        });
}

function createWrapper(layerId) {
    const layer = document.querySelector(`#mountain svg ${layerId}`);
    if (!layer) return;

    const wrapper = document.createElementNS("http://www.w3.org/2000/svg", "g");
    wrapper.setAttribute("id", `${layerId.slice(1)}_wrapper`);

    layer.parentNode.insertBefore(wrapper, layer);
    wrapper.appendChild(layer);
}


loadSVG();

function setAnimationScroll() {
    gsap.registerPlugin(ScrollTrigger);

    let runAnimation = gsap.timeline({
        scrollTrigger: {
            trigger: ".banner",
            start: "top top",
            end: "+=1000",
            scrub: true,
            pin: true
        }
    });

    runAnimation.add([
        gsap.to("#cloud10_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud9_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud8_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud7_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud6_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud5_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud4_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud3_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud2_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud1_fixed", { y: -1500, duration: 2 }),
        gsap.to("#cloud2b", { y: -1500, duration: 2 }),
        gsap.to("#cloud1b", { y: -1500, duration: 2 }),
        gsap.to("#cloud10", { y: -1500, duration: 2 }),
        gsap.to("#cloud9", { y: -1500, duration: 2 }),
        gsap.to("#cloud8", { y: -1500, duration: 2 }),
        gsap.to("#cloud7", { y: -1500, duration: 2 }),
        gsap.to("#cloud6", { y: -1500, duration: 2 }),
        gsap.to("#cloud5", { y: -1500, duration: 2 }),
        gsap.to("#cloud4", { y: -1500, duration: 2 }),
        gsap.to("#cloud3", { y: -1500, duration: 2 }),
        gsap.to("#cloud2", { y: -1500, duration: 2 }),
        gsap.to("#cloud1", { y: -1500, duration: 2 })
    ])
    .add([
        gsap.to("#layer_1", {
            scale: 1.4,
            x: -250,
            y: 0,
            transformOrigin: "50% 0%",
            duration: 2
        }),
        gsap.to("#layer_2", {
            scale: 1.2,
            transformOrigin: "50% 0%",
            duration: 2
        })
    ]);
}

I have an AG Grid, implemented in React/Typescript. It automatically updates with new data, and the columns have filters. When new data comes in, the grid reloads with the changes, which closes the filter dialog if it’s open. That’s not ideal. It seems like a viable solution would be to track when the dialog is open, and hold off on updates while it’s open. I can track when the filter dialog opens (onFilterOpened), or when it changes (onFilterChanged), but I’m not certain how to detect closing the dialog without making a change by clicking off of it so that I can resume changes.

Here’s the event code (which is basically just console logs right now) based on what an AI model suggested:

const onFilterOpened = () => {
  console.log("Filter opened.");
  setIsFilterDialogOpen(true);
};

const onSortChanged = () => {
  if (gridApiRef.current) {
    columnState.current = gridApiRef.current.getColumnState();
  }
};

const onFilterChanged = (event: { api: GridApi; }) => {
  if (
    event.api.getFilterModel() &&
    Object.keys(event.api.getFilterModel()).length > 0
  ) {
    console.log("Filter dialog is opened");
    setIsFilterDialogOpen(true);
  } else {
    console.log("Filter closed.");
    setIsFilterDialogOpen(false);
  }

  console.log("Filter changed");
};

And set up here:

<AgGridReact  
  className={"ag-theme-astro"}  
  columnDefs={colDefGrouped}  
  defaultColDef={defaultColDef}  
  rowData={groupedRowData}  
  domLayout="autoHeight"  
  pagination={true}  
  paginationPageSize={20}  
  isFullWidthRow={isFullWidthRow}  
  fullWidthCellRenderer={fullWidthCellRenderer}  
  getRowHeight={getRowHeight}  
  onGridReady={onGridReady}  
  onFilterChanged={onFilterChanged}
  onFilterOpened={onFilterOpened}
  data-testid="groupedGrid"
/>

I get the “Filter opened” message when it opens, and “Filter dialog is opened” as I type in changes in the filter. But nothing when it closes.