spirit-router/lib/render.js

fast router for spirit

"use strict";

var spirit = require("spirit").node;
var path = require("path");

/*
 * The purpose of renderables is to allow for a "low-level" way
 * of handling the result of a route that should apply for
 * _all_ instances of the specific type.
 *
 * All the default handling for the types below can be replaced
 * or extended, just as new types can be added.
 *
 * Please keep in mind that all response bodys must eventually
 * be either a string, buffer, stream, or undefined.
 * Otherwise spirit node adapter will not know how to write
 * the response back to the requesting client.
 */
var renderables = {
  "object": function object(request, body) {
    return spirit.response(JSON.stringify(body)).type("json");
  },

  "array": function array(request, body) {
    return spirit.response(JSON.stringify(body)).type("json");
  },

  "string": function string(request, body) {
    return spirit.response(body);
  },

  "buffer": function buffer(request, body) {
    return spirit.response(body).type("html");
  },

  "null": function _null(request, body) {
    return spirit.response();
  },

  "file-stream": function fileStream(request, body) {
    return spirit.file_response(body);
  }
};

/**
 * Renders a Response of the return of a route
 * from a matching renderable type
 *
 * If it's already a Response nothing happens.
 * If it's a response map, it is left untouched but
 * converted to a Response.
 *
 * @param {http.Request} req - node http Request object
 * @return {Response}
 */
var render = function render(req, resp) {
  if (spirit.utils.is_Response(resp)) {
    return resp;
  }

  if (spirit.is_response(resp)) {
    return spirit.response(resp);
  }

  var t = spirit.utils.type_of(resp);

  if (typeof renderables[t] === "function") {
    return renderables[t](req, resp);
  }

  // any unknown renderable types such as:
  // boolean, number, function
  // just get packaged as a Response
  return new spirit.Response(resp);
};

module.exports = {
  renderables: renderables,
  render: render
};