What category / filter structure is this using? Nested Interval?

Question

You can see on their category links that it's quite obvious that the only portion of their URL that matters is the small hash near the end of the URL itself.

For instance, Water Heaters category found under Heating/Cooling is: http://www.lowes.com/Heating-Cooling/Water-Heaters/_/N-1z11ong/pl?Ns=p_product_avg_rating|1

and Water Heaters category found under Plumbing is: http://www.lowes.com/Plumbing/Water-Heaters/_/N-1z11qhp/pl?Ns=p_product_avg_rating|1

That being said, obviously their structure could be a number of different things... But the only thing I can think is it's a hex string that gets decoded into a number and denominator but I can't figure it out...

apparently it's important to them to obfuscate this for some reason?

Any ideas?

UPDATE
At first I was thinking it was some sort of base16 / hex conversion of a standard number / denom or something? or the ID of a node and it's adjacency?

Does anyone have enough experience with this to assist?

Answer 1

They are building on top of IBM WebSphere Commerce. Nothing fancy going on here, though. The alpha-numeric identifiers N-xxxxxxx are simple node identifiers that do not capture hierarchical structure in themselves; the structure (parent nodes and direct child nodes) is coded inside the node data itself, and there are tell-tale signs to that effect (see below.) They have no need for nested intervals (sets), their user interface does not expose more than one level at a time during normal navigation.

Take Lowe's.

If you look inside the cookies (WC_xxx) as well as see where they serve some of their contents from (.../wcsstore/B2BDirectStorefrontAssetStore/...) you know they're running on WebSphere Commerce. On their listing pages, everything leading up to /_/ is there for SEO purposes. The alpha-numeric identifier is fixed-length, base-36 (although as filters are applied additional Zxxxx groups are tacked on -- but everything that follows a capital Z simply records the filtering state.)

Let's say you then wrote a little script to inventory all 3600-or-so categories Lowe's currently has on their site. You'd get something like this:

N-1z0y28t /Closet-Organization/Wood-Closet-Systems/Wood-Closet-Kits
N-1z0y28u /Closet-Organization/Wood-Closet-Systems/Wood-Closet-Towers
N-1z0y28v /Closet-Organization/Wood-Closet-Systems/Wood-Closet-Shelves
N-1z0y28w /Closet-Organization/Wood-Closet-Systems/Wood-Closet-Hardware
N-1z0y28x /Closet-Organization/Wood-Closet-Systems/Wood-Closet-Accessories
N-1z0y28y /Closet-Organization/Wood-Closet-Systems/Wood-Closet-Pedestal-Bases
N-1z0y28z /Cleaning-Organization/Closet-Organization/Wood-Closet-Systems
N-1z0y294 /Lighting-Ceiling-Fans/Chandeliers-Pendant-Lighting/Mix-Match-Mini-Pendant-Shades
N-1z0y295 /Lighting-Ceiling-Fans/Chandeliers-Pendant-Lighting/Mix-Match-Mini-Pendant-Light-Fixtures
N-1z0y296 /Lighting-Ceiling-Fans/Chandeliers-Pendant-Lighting/Chandeliers
...
N-1z13dp5 /Plumbing/Plumbing-Supply-Repair
N-1z13dr7 /Plumbing
N-1z13dsg /Lawn-Care-Landscaping/Drainage
N-1z13dw5 /Lawn-Care-Landscaping
N-1z13e72 /Tools
N-1z13e9g /Cleaning-Organization/Hooks-Racks
N-1z13eab /Cleaning-Organization/Shelves-Shelving/Laminate-Closet-Shelves-Organizers
N-1z13eag /Cleaning-Organization/Shelves-Shelving/Shelves
N-1z13eak /Cleaning-Organization/Shelves-Shelving/Shelving-Hardware
N-1z13eam /Cleaning-Organization/Shelves-Shelving/Wall-Mounted-Shelving
N-1z13eao /Cleaning-Organization/Shelves-Shelving
N-1z13eb3 /Cleaning-Organization/Baskets-Storage-Containers
N-1z13eb4 /Cleaning-Organization
N-1z13eb9 /Outdoor-Living-Recreation/Bird-Care
N-1z13ehd /Outdoor-Living
N-1z13ehn /Appliances/Air-Purifiers-Accessories/Air-Purifiers
N-1z13eho /Appliances/Air-Purifiers-Accessories/Air-Purifier-Filters
N-1z13ehp /Appliances/Air-Purifiers-Accessories
N-1z13ejb /Appliances/Humidifiers-Dehumidifiers/Humidifier-Filters
N-1z13ejc /Appliances/Humidifiers-Dehumidifiers/Dehumidifiers
N-1z13ejd /Appliances/Humidifiers-Dehumidifiers/Humidifiers
N-1z13eje /Appliances/Humidifiers-Dehumidifiers
N-1z13elr /Appliances
N-1z13eny /Windows-Doors

Notice how entries are for the most part sequential (it's a sequential identifier, not a hash), mostly though not always grouped together (the identifier reflects chronology not structure, it captures insertion sequence, which happened in single or multiple batches, sometimes years and thousands of identifiers apart, at the other end of the database), and notice how "parent" nodes always come after their children, sometimes after holes. These are all tell-tale signs that, as categories are added and/or removed, new versions of their corresponding parent nodes are rewritten and the old, superseded or removed versions are ultimately deleted.

If you think there's more you need to know you may want to further inquire with WebSphere Commerce experts as to what exactly Lowe's might be using specifically for its N-xxxxxxx catalogue (though I suspect that whatever it is is 90%+ custom.) FWIW I believe Home Depot (who also appear to be using WebSphere) upgraded to version 7 earlier this year.

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UPDATE Joshua mentioned Endeca, and it is indeed Endeca (those N-xxxxxxx identifiers) that is being used behind Websphere in this case (though I believe since the acquisition of Endeca Oracle is pushing SUN^H^H^Htheir own Java EE "Endeca Server" platform.) So not really a 90% custom job despite the appearances (the presentation and their javascripts are heavily customized, but that's the tip of the iceberg.) You should be able to use Solr as a substitute.