Bug: Price Alert received when the price increases

[biancadanforth]

While reviewing PR #120 , I noticed that while tracking the product on Osmose's handy fake product page, I received a price alert when the price increased.

We should review our price checking logic to make sure we only show the alert when the price has decreased from the original price by the threshold.

[groovecoder]

Saw the same issue.

[muccimoz]

Moved this into Reserve Backlog so issue #187 could be added to the MVP Backlog for November.

[Osmose]

So this one is interesting; the cause is in how we calculate the price alert from the "last high price":

1. Initial price is $1.00, user starts tracking.
2. Price jumps up to $28.00, new high point.
3. Price drops to $3.00, which is both >10% drop from the high point, as well as more than $10 cheaper than the high point. Price alert is triggered.

Currently the price alert is showing the original price when tracking started in both the notification and the popup panel. The popup panel always shows a percent difference between the current price and the original price; it does not take the high price into account, unlike the notification/price alerts.

The easiest fix is to update the notification to show the high point as the "was" price, and keep the popup as-is. In the original case for this bug, it would show something like "Was $34.00, Now $28.00", and if the user viewed the popup panel, it would show $28.00 as the current price, "was $1.00" as the original price, and a 280% price increase (alongside a price alert icon).

@chuckharmston @javaun Does that sound okay?

[biancadanforth]

Currently, I am only sending along the original price (price_orig) in telemetry whenever a product card or system notification is interacted with.

@chuckharmston If we are triggering price alerts based on a high price (which I vaguely remember, but didn't think about at the time of writing METRICS.md), should this price also be included in telemetry as an extra_key? I am thinking specifically for the send_notification telemetry event at least.

[chuckharmston]

@Osmose: your proposal is fine; the ultimate utility here is to tell users when prices are dropping, so they can save money. This does that. A clearer alternative would be something like Originally $1.00, high of $34.00, currently $3.00, but I wouldn't block MVP if that's much of a lift.

@biancadanforth we should include any variables used to determine whether or not it's appropriate to display the notification, so that'd be very helpful.

[javaun]

+1. It's also fine to go live and see what price fluctuations look like IRL. Between user reports and the price change data that comes back via data collection, we'll know more. Another plus to Test Pilot