joonas-fi/shopping-list-manager

Listen for barcode scans from a barcode reader and add their product names to shopping list

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Listen for barcode scans from a barcode reader and add their product names to shopping list

Overview

flowchart TD
    subgraph "Physical barcode reader"
      barcodeentered[Barcode scanned]
    end
    subgraph "Todoist server"
        shoppinglist[Shopping list]
    end
    subgraph "Todoist clients"
        myphone[My phone]
        familymemberphone[Family member's phones]
        homeassistant[Home Assistant dashboard\nalways visible on our home wall]
    end
    subgraph "Shopping list manager"
        foundfromlocalDB?[Have we seen this barcode before?\nCheck from our own local DB of before-seen barcodes]
        useunnamedproduct[Have barcode whose product name\nwe don't yet know]
        websearch[Do a web search\non Google]
        aiextractproductname[Use ChatGPT to extract product name\nfrom web search result titles]
        addtoshoppinglist[Add product name to shopping list]
        namenotknown[ERROR: Product name not known]
    end

    barcodeentered --> foundfromlocalDB?
    foundfromlocalDB? -- yes --> addtoshoppinglist
    foundfromlocalDB? -- no --> useunnamedproduct --> websearch -- have results --> aiextractproductname -- success --> addtoshoppinglist
    aiextractproductname -. success: store name\nso we know next time .-> foundfromlocalDB?
    websearch -- no results --> namenotknown
    aiextractproductname -- extraction fails --> namenotknown
    addtoshoppinglist --> shoppinglist
    namenotknown  -. fallback: add bare barcode .-> shoppinglist

    shoppinglist --> myphone
    shoppinglist --> familymemberphone
    shoppinglist --> homeassistant

Loading

How to run

First source app.env (which has the ENV variables from the configuration section), then:

docker run --rm -it --device /dev/input/by-id/usb-NT_USB_Keyboard-event-kbd:/dev/barcode-reader -e OPENAI_API_KEY -e TODOIST_TOKEN -e TODOIST_PROJECT_ID -e GOOGLE_SEARCH_CUSTOM_SEARCH_ENGINE_ID -e GOOGLE_SEARCH_API_KEY ghcr.io/joonas-fi/shopping-list-manager:latest

Hardware

Should work with any barcode reader that works on Linux. The wireless ones are really convenient.

I used this: NETUM NT-1228BL

Configuration

You'll need to configure ENV variables:

• BARCODE_READER (example /dev/input/by-id/usb-NT_USB_Keyboard-event-kbd)
• OPENAI_API_KEY (create here)
• TODOIST_TOKEN
• TODOIST_PROJECT_ID
• GOOGLE_SEARCH_CUSTOM_SEARCH_ENGINE_ID
• GOOGLE_SEARCH_API_KEY (get here)
• WEBAPP_BASEURL (optional) base URL of the web app (so we can make links back to it)

Resolving unknown barcodes

There are web APIs to barcode databases where you can resolve the product name from.

However those are either bad (only have small subset of real-world barcodes) or really expensive (I'm not paying hundreds of dollars a month for this use case), so I opted to use web search as a "database".

External services

• Todoist
• For resolving unknown barcodes:
  • Google
  • ChatGPT