Sidewinder Contract

Service Interface Schematics

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](https://www.npmjs.com/package/@sidewinder/contract)

## Overview Sidewinder Contracts are JSON Schema interface schematics that describe callable methods on remote services. This package extends the [Sidewinder Types](../types/readme.md) package. It includes an additional Contract type that can be used to define a strict Service contract. Contracts are used both for data validation, as well as TypeScript type inference. They can also be published as machine readable documentation to remote systems. Licence MIT ## Contents - [Overview](#Overview) - [Install](#Install) - [Contracts](#Contracts) - [Formats](#Formats) ## Install ```bash $ npm install @sidewinder/contract ``` ## Contracts The following creates a contract where the `server` exposes a `foo` function, and the `client` exposes a `bar` function. Servers and Clients are responsible for implementing these functions, with the `client` functions only implementable on `WebSocketClient` instances. ```typescript import { Type } from '@sidewinder/contract' const Contract = Type.Contract({ format: 'json', server: { foo: Type.Function([Type.String()], Type.String()), }, client: { bar: Type.Function([Type.String()], Type.String()), }, }) ``` ## Formats Contracts can specify a `format` option to inform Client and Server the message encoding format that should be used to exchange messages. Sidewinder provides encoding options for `json` and `msgpack` with `json` being the default. By setting the `format` to `msgpack`, Sidewinder can exchange binary buffers of type `Uint8Array`. The following uses the `msgpack` format. ```typescript import { Type } from '@sidewinder/contract' const Contract = Type.Contract({ format: 'msgpack', server: { test: Type.Function([Type.String()], Type.String()), }, }) ```