Req.js simple fetch API wrapper with request and response processors.

Req.js

export default class Req {
  constructor({headers = {}, preProcessors = [], postProcessors = []} = {}) {
    this.options = {};
    this.options.headers = headers;
    this.options.mode = "cors";

    this.preProcessors = preProcessors;
    this.postProcessors = postProcessors;

    Object.freeze(this.options);
  }

  send({method, url, body} = {}) {
    const options = {headers: this.headers};

    if (body) options.body = body;

    const request = this.preProcessors.reduce((request, preProcessor) => {
      return preProcessor(request);
    }, new Request(url, options));

    return fetch(request).then((response) => {
      return this.postProcessors.reduce((response, postProcessors) => {
        return postProcessors(response);
      }, response);
    });
  }

  get(url) {
    return this.send({method: "GET", url});
  }

  delete(url) {
    return this.send({method: "DELETE", url});
  }

  post(url, body) {
    return this.send({method: "POST", url, body});
  }

  put(url, body) {
    return this.send({method: "PUT", url, body});
  }

  patch(url, body) {
    return this.send({method: "PATCH", url, body});
  }
}