Validations with Zod

Once you have declared your schema you can access the corresponding Zod schema for it.

The Zod schema will not only take into account:

• Type of the column.
• Nullability.
• Specific column data type validations that match validations at database level. For example, the range of an integer is: -2147483648 to +2147483647.

The schema will also reject explicit undefined values when parsing.

You can read more about the specific validations for each column data type in the Column Types API

Retrieving the Zod schema

Zod schemas are made available through the zodSchema function from @monolayer/pg/zod.

const users = table({
  columns: {
    id: integer().generatedAlwaysAsIdentity(),
    name: text(),
    createdAt: timestampWithTimeZone().default(sql`now`).notNull(),
  },
  constraints: {
    primaryKey: primaryKey(["id"]),
  },
});

const usersZodSchema = zodSchema(users);

Schema Types

Each column has a TypeScript type for input and output values (parsed) in the schema. The output values match the select type for the column(except bytea columns *)

(*) Since Buffer is a Node.js API, the schema will not coerce the input to Buffer for browser compatibility. The output type will be the same as the input type.

Column	Input	Output
bigint	bigint | number | string	string
bigserial	bigint | number | string	string
bit	string	string
bitVarying	string	string
boolean	boolean | Boolish*	boolean
bytea	Buffer | string	Buffer | string
characterVarying	string	string
character	string	string
cidr	string	string
date	Date | string	Date
doublePrecision	bigint | number | string	string
enumerated	enum values	enum values
inet	string	string
integer	number | string	number
json	JsonValue*	JsonValue*
jsonb	JsonValue*	JsonValue*
macaddr	string	string
macaddr8	string	string
numeric	bigint | number | string	number
real	bigint | number | string	string
serial	number | string	number
smallint	number | string	number
time	string	string
timeWithTimeZone	string	string
timestamp	Date | string	Date
timestampWithTimeZone	Date | string	Date
tsquery	string	string
tsvector	string	string
uuid	string	string
xml	string	string

(*) Boolish and JsonValue are defined as follows:

type Boolish = "true" | "false" | "yes" | "no" | 1 | 0 | "1" | "0" | "on" | "off";
type JsonArray = JsonValue[];
type JsonValue = boolean | number | string | Record<string, unknown> | JsonArray;

Example

const userRole = enumType("user_role", ["admin", "user"]);
const users = table({
  columns: {
    id: integer().generatedAlwaysAsIdentity(),
    name: text(),
    role: enumerated(userRole).notNull(),
    orderCount: integer().notNull().default(0),
    createdAt: timestampWithTimeZone().default(sql`now`).notNull(),
  },
  constraints: {
    primaryKey: primaryKey(["id"]),
  },
});
const schema = zodSchema(users);
type InputType = z.input<typeof schema>;
type OutputType = z.output<typeof schema>;

InputType will be:

type InputType = {
  id: never;
  name?: string | null | undefined;
  role: "user" | "admin";
  orderCount: number | string | undefined;
  createdAt?: Date | string | undefined;
}

OutputType will be:

type OutputType = {
  id: never;
  name?: string | null | undefined;
  orderCount?: number | undefined;
  role: "user" | "admin";
  createdAt?: Date | undefined;
}