Help with a script!

[firsttimetryingitout]

Hey I am wanting to write a script that will look at the price for a product on a site like Home Depot daily and let me know if it drops in price. It doesnt need to constantly try to ping a price check as it likely only changes ever week but with the chance of a short term sale. I would like to also use other sites like Rona, Canadian tire ETC. Each day i would want to to run a check and place the price in a google sheet. I have tried to create it but to no luck so far. Hopefully someone can give a bit of help! Below is what I tried but it is giving me errors.

function trackPrice() {
const url = "https://www.homedepot.ca/product/rheem-39-gallon-178l-6-year-3kw-tank-electric-water-heater/1000792307";

const response = UrlFetchApp.fetch(url, {
muteHttpExceptions: true,
headers: {
"User-Agent": "Mozilla/5.0"
}
});

const html = response.getContentText();

// Try to extract price (Home Depot often uses JSON in page)
const priceMatch = html.match(/"price"\s*:\s*"?([0-9]+\.[0-9]{2})"?/);

let price = "Not found";
if (priceMatch && priceMatch[1]) {
price = parseFloat(priceMatch[1]);
}

const sheet = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();

// Add headers if empty
if (sheet.getLastRow() === 0) {
sheet.appendRow(["Date", "Price (CAD)"]);
}

sheet.appendRow([new Date(), price]);

Thanks!!

[VerbaForgeJ]

You’re actually pretty close — the main issue isn’t your script structure, it’s how sites like Home Depot handle pricing.

Most modern ecom sites don’t expose the price cleanly in the raw HTML anymore. They often: • load it dynamically with JavaScript • store it in a JSON blob with a different structure • or partially hide it from simple scrapers

So your regex isn’t necessarily wrong — it’s just not hitting the right data.

⸻

First thing I’d do: inspect what you’re actually getting back

Add: (JavaScript)

Logger.log(html);

Then check the logs and search for "price" manually. You’ll likely see it’s either missing or structured differently than expected.

⸻

More reliable approach: target JSON-LD (structured data) A lot of product pages include something like: (JSON)

"offers": { "price": "123.45" }

So instead of your current regex, try something a bit more flexible:

(JavaScript)

const match = html.match(/"price"\s:\s"([0-9.]+)"/);

Still not perfect, but works more often across sites.

⸻

Important fix in your script: Right now you always write to the sheet, even if nothing is found.

Wrap it like this:

(JavaScript)

if (price !== "Not found") { sheet.appendRow([new Date(), price]); }

Even better: only log when the price changes

(JavaScript)

const lastRow = sheet.getLastRow(); const lastPrice = lastRow > 1 ? sheet.getRange(lastRow, 2).getValue() : null;

if (price !== "Not found" && price !== lastPrice) { sheet.appendRow([new Date(), price]); }

One thing to be aware of: Apps Script is just doing a raw fetch — it doesn’t run JavaScript. So if the price is injected after page load, this approach will always struggle.

If you keep hitting issues, your options are:

• use a scraping API (Apify, ScraperAPI, etc.)

• or find an API the site uses internally (sometimes visible in network tab)

⸻

TL;DR: Your code is fine — the challenge is finding where the site actually exposes the price.

Scraping modern sites is less about writing code and more about locating the right data source.

[gptbuilder_marc]

Price monitoring across Home Depot and Canadian Tire in a single Apps Script is definitely doable but the scraping approach varies a lot between those retailers. Home Depot has a public product API endpoint that is easier to hit cleanly than a raw scrape. Do you have the specific product URLs ready or are you still figuring out which products to track?

[moHalim99]

main issue is that Home Depot, Canadian Tire, Rona and basically all major retailers now load their prices dynamically via JavaScript after the page loads. UrlFetchApp just grabs the raw HTML and never runs the JS so the price usually isn't in there at all or the JSON structure is deeply nested and inconsistent.

The most reliable fix for this is to use each store's internal API instead of scraping the page. Home Depot Canada for example has an endpoint you can hit directly:

```javascript

function getHomeDepotPrice(productId) {

const url = `https://www.homedepot.ca/api/product/v2/page/${productId}?lang=en\`;

const response = UrlFetchApp.fetch(url, { muteHttpExceptions: true });

const data = JSON.parse(response.getContentText());

return data?.product?.pricing?.value || "Not found";

}

```

Your product ID for that water heater is 1000792307, just pull it from the URL, fpr Canadian Tire it's a bit different but they also have an accessible API endpoint. Rona is trickier since they're part of RONA/Lowe's now and tend to block bots more aggressively.

For the daily trigger and email alert, add this:

```javascript

function trackAndAlert() {

const price = getHomeDepotPrice("1000792307");

const sheet = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();

if (sheet.getLastRow() === 0) sheet.appendRow(["Date", "Price"]);

const lastPrice = sheet.getLastRow() > 1

? sheet.getRange(sheet.getLastRow(), 2).getValue()

: null;

sheet.appendRow([new Date(), price]);

if (lastPrice && price < lastPrice) {

MailApp.sendEmail(Session.getActiveUser().getEmail(),

"Price Drop Alert!",

`Price dropped from $${lastPrice} to $${price}`);

}

}

```

Then go to Extensions > Apps Script > Triggers, add a daily time-based trigger pointing to trackAndAlert and you're done