Storefront stock visualizer

Opt-in, off by default.

Enable: cataloginventory/stock_visualizer/enabled, in Stores › Configuration › Catalog › Inventory › Storefront Stock Visualizer.

The visualizer renders an Availability panel on the product page, driven by MSI. It ships as the additive Magento_InventoryStockVisualizer module and does not replace or alter any core inventory module.

What it shows

The general settings sit at the top level of the configuration group; two subsections group the rest, Per-source breakdown and Composite product types. The display type and the level thresholds can be overridden per product through a dedicated Stock Visualizer attribute group.

Display type. level renders a traffic-light state (high, medium, low, out) with no exact quantity exposed; quantity renders the exact salable number. The display type applies to every product type: in level mode no type ever reveals a number, while the per-type mode below still defines the structure (aggregate, per component or selected variant). Level per-component rows render a colour-coded availability bar instead of a count.
Scope, for single-SKU products. aggregate shows a single availability; per_source breaks it down per source. It applies to simple, virtual and downloadable products and to the selected configurable variant; composite aggregate and per-component displays are always aggregated. Per-source availability nets the physical source quantity against that source’s reservation balance, and degrades to the physical quantity when source-level reservations are off.
Delivery mode, for availability fetched over AJAX (exact quantity, and the interactive composite types). on_demand fetches on a button click and instant fetches on page load. Server-rendered availability always shows on load.

Level mode with the default thresholds. Both thresholds are strict: a quantity of exactly 10 is medium and exactly 3 is low.

Availability is computed server-side against the current website’s stock, resolved through the sales channel, so one website’s cached fragment can never stand in for another’s. Out-of-stock products render the status alone: the panel skips the client component, so no call to action is offered and no fragment is requested.

Composite product types

Simple, virtual and downloadable products use the single-SKU path above. Each composite type has its own display mode, because a GetProductSalableQtyInterface read is undefined for a type that does not manage its own stock.

Type	Modes (default first)	Interactive	What it shows
Configurable	`variant` · `children` · `status`	`variant`	`variant`: the selected option combination’s availability, per source when enabled; `children`: every variant’s availability; `status`: one in-stock or out-of-stock word.
Bundle	`max` · `children` · `status`	`max`	`max`: how many of the current selection can be ordered, recomputed as options and quantities change; `children`: each selection’s stock; `status`: aggregate word.
Grouped	`children` · `status`	no	`children`: each associated product’s stock, plus an optional complete-sets calculator; `status`: aggregate word.

The interactive modes read the live selection from the native storefront widgets: the swatch or dropdown configurable resolves the chosen child, and the bundle reads the priceBundle option config. The client sends the child product id, never a SKU; the server resolves it.
The module removes the core availability badges for simple, virtual, grouped, configurable, bundle and downloadable products, so the panel never sits next to a duplicate or contradictory badge. Options, swatches and links are left untouched. The removal lives in the inventory_stockviz_panel layout handle with the panel, which is applied only while the module is enabled, so switching it off gives the product page its core badge back.

Configuration

All settings live under cataloginventory/stock_visualizer.

Setting	Default	Purpose
`enabled`	`0`	Show the panel on the product page.
`display_type`	`level`	`level` (traffic light) or `quantity` (exact number).
`mode`	`on_demand`	`on_demand` (fetch on click) or `instant` (fetch on load) for AJAX availability.
`ttl`	`0`	Public-cache lifetime of the AJAX fragments, in seconds; `0` purges by tag only.
`level_basis`	`quantity`	Compare the salable quantity to absolute thresholds or to a per-product full quantity.
`level_high`	`10`	Above this the level is high.
`level_low`	`3`	Above this, and up to `level_high`, the level is medium; at or below it, low.
`scope`	`aggregate`	Single-SKU breakdown: `aggregate` or `per_source`.
`show_source_labels`	`1`	Show the source name on each per-source row.
`hide_empty_sources`	`1`	Omit out-of-stock sources from the per-source breakdown.
`composite_configurable_mode`	`variant`	`variant`, `children` or `status`.
`composite_bundle_mode`	`max`	`max`, `children` or `status`.
`composite_grouped_mode`	`children`	`children` or `status`.
`composite_grouped_sets_calculator`	`0`	Show the complete-sets calculator (grouped `children` only).

Per-product overrides, in the Stock Visualizer attribute group, cover the display type and the level thresholds: stockviz_display_type, stockviz_level_basis, stockviz_level_high, stockviz_level_low and stockviz_full_qty (the percentage reference). Scope, delivery mode and the composite modes are store-scoped only.

Keeping the panel fresh

The panel is cached with the page, so the module keeps it fresh with a dedicated cache tag, inv_stockviz_<productId>, that leaves the surrounding product page cache untouched. The tag is purged at three seams, all best-effort: a failure is logged and never breaks checkout or reindex.

Demand. A plugin on AppendReservationsInterface catches reservation writes (order, cancel, refund, RMA, import). In level mode it purges only when the level bucket changes; in quantity mode it purges every touched SKU.
Supply. Plugins on SourceItemsSaveInterface and SourceItemsDeleteInterface snapshot the old per-source quantity and purge on quantity changes that never flip salability, which the index-driven backstop would miss.
Salability backstop. A salability-change processor in the inventory indexer purges on flips that arrive through reindex.

Three seams feed one decider. Only the panel's own cache tag, inv_stockviz_<productId>, is purged: right away when the inventory index runs on save, through the queue when it runs on schedule.

All three feed one decider, ResolveSkusToPurge, which applies the enabled gate and the display-mode rules, and DispatchPurge, which either flushes synchronously or offloads to the queue. The async path collapses a burst of writes for the same SKU into a single purge through a short-lived cache guard; the consumer clears the guard first and then flushes live state, so the last write wins.

The purge strategy follows the inventory indexer: when the Inventory index runs on schedule, purges go to the queue; when it runs on save, they flush synchronously. The queue is database-backed, so no RabbitMQ is required.

Configuration changes show immediately. Every fragment request carries a short config fingerprint (_cv) derived from the display settings. Changing any display setting mints a fresh cache key, so the new output is served on the next load without a manual cache flush.

Operational requirements

bin/magento setup:upgrade registers the per-product attributes and the message-queue topology.
bin/magento setup:di:compile for production mode.
When the purge strategy resolves to the queue, run the consumer bin/magento queue:consumers:start inventory.stockvisualizer.purge, or the standard consumer cron.

Generating performance-toolkit fixtures

While this module is enabled, setup:performance:generate-fixtures aborts with The entity ID field for the "queue_message" table wasn't found. Saving the generator’s template product writes source items, which fires the supply seam and publishes a purge message, so queue_message ends up among the tables the generator treats as part of the product entity. Disable the module while generating the catalog:

bin/magento module:disable Magento_InventoryStockVisualizer
bin/magento setup:performance:generate-fixtures <profile>
bin/magento module:enable Magento_InventoryStockVisualizer
bin/magento setup:di:compile

This affects fixture generation only, never storefront or admin behaviour.

Extending it

Public service contracts live in the module’s Api namespace:

GetStockViewInterface builds the availability view for a SKU in a stock, optionally typed so composite products resolve their aggregate and child breakdown.
Api\Data\StockViewInterface and Api\Data\SourceViewInterface carry the aggregate and per-source availability; Api\Data\ChildViewInterface carries one composite child’s label and availability.

The AJAX fragments are served by controllers under the inventory_stockviz front name: product/view (single SKU or configurable variant), product/children (composite child breakdown and the grouped sets calculator) and product/bundleMax (sellable count for a bundle selection).

Swap the default GetStockViewInterface implementation through a DI preference to change how availability is computed without touching the panel, the controller or the caching layer.