Examples & RecipesRecipe Library
Compute fields and calculate totals live
Automatically compute field values, totals, and balances with server-side guarantees and instant Admin UI reactivity.
Automatically compute field values, totals, and balances with server-side guarantees and instant Admin UI reactivity.
Use this when
- calculate order totals from sibling inputs
- compute remaining balances automatically
- update field values live as an editor types
- guarantee computed values in the database
Dyrected concepts
beforeChange, admin.hooks.onChange, defaultValue, readOnly
Additional packages: No additional packages.
Decisions and cautions
Use this recipe only when its runtime matches the project you are documenting or building. Cloud recipes must stay inside the managed content backend boundary. Self-hosted recipes may use the server runtime, database, hooks, and infrastructure you control.
Complete recipe
This is the canonical source compiled and behavior-tested by @dyrected/knowledge.
import { defineCollection, defineNumberField, defineSelectField, defineTextField } from "@dyrected/core";
export function calculateOrderTotals(item: Record<string, any> = {}) {
const quantity = Number(item.quantity) || 0;
const unitPrice = Number(item.unitPrice) || 0;
const discount = Number(item.discount) || 0;
const subtotal = quantity * unitPrice;
const total = Math.max(0, subtotal - discount);
return { subtotal, total };
}
export const Orders = defineCollection({
slug: "orders",
hooks: {
beforeChange: [
({ data, doc, operation }) => {
const merged = { ...(doc || {}), ...data };
const { total } = calculateOrderTotals(merged);
return {
...data,
totalAmount: total,
};
},
],
},
fields: [
defineNumberField({
name: "quantity",
label: "Quantity",
required: true,
defaultValue: 1,
}),
defineNumberField({
name: "unitPrice",
label: "Unit Price (₦)",
required: true,
defaultValue: 10000,
}),
defineNumberField({
name: "discount",
label: "Discount (₦)",
defaultValue: 0,
}),
defineNumberField({
name: "totalAmount",
label: "Total Amount (₦)",
admin: {
readOnly: true,
hooks: {
onChange: ({ siblingData }) => calculateOrderTotals(siblingData).total,
},
},
}),
defineSelectField({
name: "paymentStatus",
label: "Payment Status",
defaultValue: "pending",
options: [
{ label: "Pending", value: "pending" },
{ label: "Partial", value: "partial" },
{ label: "Paid", value: "paid" },
],
}),
defineNumberField({
name: "amountPaid",
label: "Amount Paid (₦)",
admin: {
hooks: {
onChange: ({ value, siblingData }) => {
const { total } = calculateOrderTotals(siblingData);
const status = siblingData.paymentStatus;
if (status === "pending") return 0;
if (status === "paid") return total;
if (status === "partial") {
if (typeof value === "number" && value > 0 && value !== total) {
return value;
}
return total;
}
return value;
},
},
},
}),
],
});