src/null_backend.ts
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import { ResultMessage } from "./messages";
import { ResultBackend } from "./result_backend";
/**
* A dummy backend. All operations will either throw or return a rejected
* `Promise`, whichever is appropriate. To be used when ignoring results.
*/
export class NullBackend implements ResultBackend {
/**
* @returns A `NullBackend` ready to fail at the earliest convenience.
*/
public constructor() { }
/**
* @returns A rejected `Promise`.
*/
public async put(): Promise<string> {
throw new Error("cannot put results onto a null backend");
}
/**
* @returns A rejected `Promise`.
*/
public async get<T>(): Promise<ResultMessage<T>> {
throw new Error("cannot get results from a null backend");
}
/**
* @returns A rejected `Promise`.
*/
public delete(): Promise<string> {
throw new Error("cannot delete results from a null backend");
}
/**
* @returns A resolved `Promise`.
*/
public async disconnect(): Promise<void> {
await this.end();
}
/**
* @returns A resolved `Promise`.
*/
public async end(): Promise<void> { }
/**
* @returns Nothing; will never return.
* @throws Error If invoked.
*/
public uri(): never {
throw new Error("cannot query the URI of a null backend");
}
}