Wishlist

A naively simple self-hosted wish list.

Introduction

This is a small program to monitor the price of items in various online stores. Given an item “identifier”, it scraps the price from an online resource provided by the store, and persists it in a local database. It has the following features:

• It has a web interface to list all the items it monitors and their current price.

• The price history is plotted on the web interface

• It sends a Telegram message whenever there is a price drop.

• It has a command line interface to manage the items.

See my personal wishlist for an example.

It does not have (and not plan to)

• User account management

• Remote management (web or CLI)

Currently the following online stores are supported:

• PlayStation 4 games (US & HK)

• Nintendo Switch games US

• Amazon US

Installation & usage

The program requires SQLite 3.

The executable itself is easy to compile and install—just run cargo build --release and copy the binary to anywhere you want. However, in order for it to work properly, there are some more pieces to the puzzle.

TLDR:

1. Compile and install the executable.

2. Configure reverse proxy and copy content of the frontend directory into reverse proxy’s static file directory.

3. Copy systemd service and timer files.

4. Maybe configure Telegram controller.

5. Add items you want to monitor.

Configuration

The program expects a configuration file named wishlist.toml. It looks at the “current directory” for it, and if not found, /etc/wishlist.toml. A configuration file looks like this (showing default values if not specified otherwise):

# The URL “directory” where the web interface runs under. For example
# if this is “wishlist”, the web interface will be at
# https://your.domain/wishlist/. Empty if not set.
url_prefix = "wishlist"
# Listening port of the HTTP server
port = 8000
# Path of the database file
db_file = "wishlist.db"
# The default price update interval
update_interval_sec = 3600
# Path of the Telegram controller. No Telegram notifications if
# not set.
telegram_notifier = "/path/to/telegram-notify-bot"

If the configuration file is not found, it loads the default settings.

Web interface

For the web interface, run wishlist serve. This starts an HTTP server at the port specified in the configuration. As always, it is recommended to run behind a reverse proxy. This provides the “API server”. I have this piece in my Nginx configuration:

location /wishlist/api {
    proxy_pass http://localhost:3585/wishlist/api;
}

given that I have url_prefix = "wishlist" and port = 3585.

The front-end is mostly a separate issue. All the front-end files are in the frontend directory in the repo. They are just static files, and you are free to let the reverse proxy handle them (keep in mind of url_prefix if set). Or you can put the frontend directory in the “current directory”, to let the builtin HTTP server serve them.

Of course, you may want to use a daemon manager like systemd to manage it. A systemd service file is included in the etc directory in the repo.

Periodic update

The HTTP server itself provides read-only access to the item list and prices. In order to monitor price changes and update the database, another instance is needed to run periodically with sub-command update (i.e. run wishlist update). There are two factors that determines how frequently the database will be updated:

• Each item has an update interval. Prices will not be updated more frequently than indicated by this value, no matter how frequently you run wishlist update. Currently this is hard-coded to be 10 minutes for Amazon, and 1 hour for other stores.

• The frequency you run wishlist update.

I use systemd to manage updates. A timer file and a service file is included in the etc directory.

Telegram notification

The program relies on telegram-bot-controller to send Telegram messages. So you will need to deploy that if you want Telegram notifications. In the future I may absorb this capability here.

Initial setup

You need to tell the program what items you want to monitor. This is done by running wishlist add followed by a store name and an item ID. Valid store names are listed at the end of src/store/mod.rs. An item ID is usually part of the URL of the product page in the store. For example, for Amazon item at https://www.amazon.com/AmazonBasics-Shaped-Silicone-Combo-Black/dp/B07LBDVJKN/, B07LBDVJKN is the ID. Therefore you can run the following command to add it to the database:

wishlist add amazon-us B07LBDVJKN

For Switch games, for example, https://www.nintendo.com/games/detail/super-mario-maker-2-switch/, the ID is super-mario-maker-2-switch. The command to add it is

wishlist add switch-us super-mario-maker-2-switch

For PlayStation games it is actually a lot more complicated, because products there can have multiple editions in the same page. I am too lazy to dive into details here, just an example: for the game at https://store.playstation.com/en-us/product/UP0102-PPSA01556_00-VILLAGEXRE7COMPB, the ID of “standard edition” is UP0102-PPSA01556_00-VILLAGEFULLGAMEX.

Ideally the program should be able to simply take a URL of the product, and automatically figure out the store and the ID(s). I am working on this. For now you will have to do this manually.