medusajs/medusa · error · MedusaError

"${contextKey}" should be present as an array in the context

Error message

"${contextKey}" should be present as an array in the context for computeActions

What it means

getComputedActionsForItems validates that the context bucket for the given contextKey (e.g., 'items', 'shipping_methods', or custom target types) exists before computing item-level adjustments. A null/undefined context for that key throws INVALID_DATA.

Source

Thrown at packages/modules/promotion/src/utils/compute-actions/line-items.ts:26

  ApplicationMethodAllocation,
  ApplicationMethodTargetType,
  calculateAdjustmentAmountFromPromotion,
  ComputedActions,
  MathBN,
  MedusaError,
  ApplicationMethodTargetType as TargetType,
} from "@medusajs/framework/utils"
import { Promotion } from "@models"
import { areRulesValidForContext } from "../validations"
import { sortLineItemByPriceAscending } from "./sort-by-price"
import { computeActionForBudgetExceeded } from "./usage"

function validateContext(
  contextKey: string,
  context: PromotionTypes.ComputeActionContext[TargetType]
) {
  if (!context) {
    throw new MedusaError(
      MedusaError.Types.INVALID_DATA,
      `"${contextKey}" should be present as an array in the context for computeActions`
    )
  }
}

export function getComputedActionsForItems(
  promotion: PromotionTypes.PromotionDTO | InferEntityType<typeof Promotion>,
  items: PromotionTypes.ComputeActionContext[TargetType.ITEMS],
  appliedPromotionsMap: Map<string, number>,
  allocationOverride?: ApplicationMethodAllocationValues
): PromotionTypes.ComputeActions[] {
  validateContext("items", items)

  return applyPromotionToItems(
    promotion,
    items,
    appliedPromotionsMap,

View on GitHub (pinned to 5e06e544a2)

Solutions

1. Always include the relevant key with at least an empty array: { items: [], shipping_methods: [] }
2. Align the promotion's application_method.target_type with the context keys you actually supply
3. Map cart items/shipping methods explicitly even when the cart is empty

Example fix

// before
const context = {}
if (cart.items.length) context.items = mapItems(cart.items)
await promotionModule.computeActions(codes, context)

// after
const context = {
  items: mapItems(cart.items),        // [] when cart is empty
  shipping_methods: mapShipping(cart.shipping_methods),
}
await promotionModule.computeActions(codes, context)

const context = { items: ctx.items ?? [], shipping_methods: ctx.shipping_methods ?? [] } as PromotionTypes.ComputeActionContext

const hasContextKey = (ctx: unknown, key: string): boolean => !!ctx && Array.isArray((ctx as any)[key])

try { await computeActions(codes, context) } catch (e) { if (e.type === MedusaError.Types.INVALID_DATA && /should be present as an array/.test(e.message)) { /* add the missing key with [] and retry */ } throw e }

When it happens

Trigger: Calling computeActions with a context object where the target-type key being computed is absent — e.g., a promotion with target_type 'items' but the context only contains shipping_methods, or the key was set to undefined via destructuring.

Common situations: Conditionally building context and skipping empty arrays (setting undefined instead of []), target_type misconfigured on the promotion, generic computeActions wrappers that forward partial contexts.

Related errors

• "items" should be present as an array in the context to comp
• "shipping_methods" should be present as an array in the cont
• Cannot add promotions to campaign where currency_code don't
• Application Method value should be a percentage number betwe
• apply_to_quantity is a required field for Promotion type of

AI-assisted analysis of medusajs/medusa@5e06e544a2 (2026-08-27). Data as JSON: /api/errors/9b49c3b037c6a304. Report an issue: GitHub.