Types

Use x.row() to define the schema you pass to CSVImporter. Each field controls how uploaded values are parsed, validated, labeled, and typed before they reach your app.

Basic Usage

import { CSVImporter, x, type Infer } from "@expresscsv/sdk";

const userSchema = x.row({
  name: x.string().label("Full Name"),
  email: x.string().email().label("Email Address"),
  age: x.number().label("Age").min(18),
  startDate: x.date().label("Start Date"),
  active: x.boolean().label("Active").optional(),
});

type UserRow = Infer<typeof userSchema>;

const importer = new CSVImporter({
  schema: userSchema,
  publishableKey: "pk_test_...",
  importIdentifier: "user-import",
});

importer.open({
  onData: async (chunk, next) => {
    const records: UserRow[] = chunk.records;
    await saveImportedUsers(records);
    next();
  },
});

Each key becomes a column the user maps to. The field type determines how values are parsed and validated before your onData callback or webhook runs.

Field Types

String - x.string()
Number - x.number()
Boolean - x.boolean()
Date - x.date()
Time - x.time()
Datetime - x.datetime()
Select - x.select()
Multiselect - x.multiselect()

Custom Validation

Use Refine for custom validators with .refine(), .refineBatch(), and suggested fixes.

If you use dynamic elements while assembling a schema, Infer<typeof schema> can widen because the exact keys are no longer guaranteed at compile time. Use dynamic schema assembly intentionally when you need runtime-driven columns.

TypeScript Inference

Use Infer<typeof schema> to extract the validated row type from your schema:

import { x, type Infer } from "@expresscsv/sdk";

const schema = x.row({
  name: x.string(),
  age: x.number(),
  active: x.boolean().optional(),
});

type Row = Infer<typeof schema>;
// { name: string; age: number; active?: boolean }

When you use that schema with CSVImporter, chunk.records is inferred automatically inside onData, so you usually do not need manual type annotations.

Basic Usage

Field Types

Custom Validation

Dynamic Schemas

TypeScript Inference

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