# Zod Schemas for apps on ICP

A collection of reusable Zod schemas and validators for common data patterns in Internet Computer applications.

[![npm version](https://img.shields.io/npm/v/@dfinity/zod-schemas.svg?logo=npm)](https://www.npmjs.com/package/@dfinity/zod-schemas) [![GitHub license](https://img.shields.io/badge/license-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)

## Table of contents

- [Installation](#installation)
- [Features](#features)

## Installation

You can use the library by installing it in your project.

```bash
npm i @dfinity/zod-schemas
```

The bundle needs peer dependencies, be sure that following resources are available in your project as well.

```bash
npm i @icp-sdk/core
```

## Features

The library implements following features:

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### :toolbox: Functions

- [inferOptionSchema](#gear-inferoptionschema)
- [inferNullishSchema](#gear-infernullishschema)
- [inferNullableSchema](#gear-infernullableschema)
- [inferResultSchema](#gear-inferresultschema)
- [createUrlSchema](#gear-createurlschema)

#### :gear: inferOptionSchema

| Function            | Type                                                 |
| ------------------- | ---------------------------------------------------- |
| `inferOptionSchema` | `<T extends z.ZodType>(schema: T) => ZodOptional<T>` |

References:

- `Option`

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/option.ts#L4)

#### :gear: inferNullishSchema

| Function             | Type                                                              |
| -------------------- | ----------------------------------------------------------------- |
| `inferNullishSchema` | `<T extends z.ZodType>(schema: T) => ZodOptional<ZodNullable<T>>` |

References:

- `Nullable`

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/option.ts#L8)

#### :gear: inferNullableSchema

| Function              | Type                                                 |
| --------------------- | ---------------------------------------------------- |
| `inferNullableSchema` | `<T extends z.ZodType>(schema: T) => ZodNullable<T>` |

References:

- `Nullish`

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/option.ts#L12)

#### :gear: inferResultSchema

| Function            | Type                                                                                                                                                                                                          |
| ------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `inferResultSchema` | `<T extends z.ZodType>(schema: T) => ZodDiscriminatedUnion<[ZodObject<{ status: ZodLiteral<"success">; result: T; }, $strict>, ZodObject<{ status: ZodLiteral<"error">; err: ZodOptional<...>; }, $strict>]>` |

References:

- `Result`

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/result.ts#L4)

#### :gear: createUrlSchema

Creates a Zod schema for validating URLs. By default, it validates that the URL protocol is HTTPS and allow usage of HTTP only locally.

| Function          | Type                                                                                                                                                      |
| ----------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `createUrlSchema` | `({ additionalProtocols, allowHttpLocally, }: { additionalProtocols?: `${string}:`[] or undefined; allowHttpLocally?: boolean or undefined; }) => ZodURL` |

Parameters:

- `options`: - Configuration options for the schema.
- `options.additionalProtocols`: - Additional protocols to allow (e.g., "wss:" or "ftp:"). ⚠️ Usage of insecure protocols is discouraged.
- `options.allowHttpLocally`: - Whether to allow HTTP for localhost and 127.0.0.1. Default: true.

Returns:

- The Zod schema with URL validation.

Examples:

const schema = createUrlSchema({
additionalProtocols: ["wss:"],
allowHttpLocally: false
});

schema.parse("https://example.com"); // Valid
schema.parse("wss://example.com"); // Valid
schema.parse("http://localhost"); // Invalid if allowHttpLocally is false

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/url.ts#L28)

### :wrench: Constants

- [Uint8ArraySchema](#gear-uint8arrayschema)
- [PrincipalTextSchema](#gear-principaltextschema)
- [PrincipalSchema](#gear-principalschema)
- [UrlSchema](#gear-urlschema)

#### :gear: Uint8ArraySchema

Zod schema to validate a value is a `Uint8Array` instance.

| Constant           | Type                                                          |
| ------------------ | ------------------------------------------------------------- |
| `Uint8ArraySchema` | `ZodCustom<Uint8Array<ArrayBuffer>, Uint8Array<ArrayBuffer>>` |

Examples:

```typescript
const result = Uint8ArraySchema.safeParse(new Uint8Array([1, 2, 3]));
console.log(result.success); // true or false
```

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/arrays.ts#L13)

#### :gear: PrincipalTextSchema

Zod schema to validate a string as a valid textual representation of a Principal.

This schema checks if the provided string can be converted into a `Principal` instance.
If the conversion fails, validation will return an error message.

| Constant              | Type        |
| --------------------- | ----------- |
| `PrincipalTextSchema` | `ZodString` |

Examples:

```typescript
const result = PrincipalTextSchema.safeParse("aaaaa-aa");
console.log(result.success); // true or false
```

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/principal.ts#L17)

#### :gear: PrincipalSchema

Zod schema to validate and transform a value into a `Principal` instance.

This schema checks if the provided value is an instance or an object representing
a `Principal` and transforms it into a valid `Principal` instance.

| Constant          | Type                                                                     |
| ----------------- | ------------------------------------------------------------------------ |
| `PrincipalSchema` | `ZodPipe<ZodCustom<Principal, Principal>, ZodTransform<any, Principal>>` |

Examples:

```typescript
const result = PrincipalSchema.safeParse(Principal.fromText("aaaaa-aa"));
console.log(result.success); // true or false
```

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/principal.ts#L48)

#### :gear: UrlSchema

Default URL schema that enforces HTTPS and allows HTTP locally.

| Constant    | Type     |
| ----------- | -------- |
| `UrlSchema` | `ZodURL` |

Examples:

UrlSchema.parse("https://example.com"); // Valid
UrlSchema.parse("http://127.0.0.1"); // Valid (localhost exception)

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/url.ts#L65)

### :nut_and_bolt: Enum

- [ZodSchemaId](#gear-zodschemaid)

#### :gear: ZodSchemaId

Enum of metadata `id` values assigned to Zod schemas in this library.

| Property        | Type              | Description                                   |
| --------------- | ----------------- | --------------------------------------------- |
| `PrincipalText` | `"PrincipalText"` | Metadata id for {@link PrincipalTextSchema }. |
| `Principal`     | `"Principal"`     | Metadata id for {@link PrincipalSchema }.     |
| `Uint8Array`    | `"Uint8Array"`    | Metadata id for {@link Uint8ArraySchema }.    |
| `Url`           | `"Url"`           | Metadata id for {@link UrlSchema }.           |

[:link: Source](https://github.com/dfinity/icp-js-canisters/tree/main/packages/zod-schemas/src/schema-id.ts#L4)

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