good-request/index.js

"use strict";
const isObject = (x) => x && (typeof x === 'object' || typeof x === 'function');
const http = require('http');


/*******************************************************************************\
**                                                                             **
**                                                                             **
**    ==================================================                       **
**    ========    npm package:  good-request    ========                       **
**    ==================================================                       **                                                                       **
**                                                                             **
**    New 7/31 version, first published version.                               **
**      "He was ten feet short; he RAN down the ramp. He RAAAN!"               **
**                                                                             **
**    nice-request, neat-request, and my-request are already taken.            **
**    better-request better back down.                                         **
**                                                                             **
**    Based on the 2020-07-31 example documented at:                           **
**      https://nodejs.org/api/http.html#http_http_request_options_callback    **
**                                                                             **
**    By wv-coder.                                                             **
**                                                                             **
**                                                                             **
**    ====  API  ====                                                          **
**                                                                             **
**    Functions provided:                                                      **
**    - basicPost         (urlString, ct,  reqText,               callback)    **
**    - retryingPost      (urlString, ct,  reqText,    nRetries,  callback)    **
**    - retryingJsonPost  (urlString,      reqObject,  nRetries,  callback)    **
**                                                                             **
**    Callback provides an object with some of the following properties:       **
**    - received:       true | undefined                                       **
**    - statusCode:     response status integer | undefined                    **
**    - text:           response body string | undefined                       **
**    - error:          error object | undefined                               **
**    - errorsRetried:  array of error objects | undefined                     **
**    - object:         response body jso | undefined                          **
**                                                                             **
**                                                                             **
\*******************************************************************************/


const     basicPost  =
exports.  basicPost  =
function  basicPost  (urlString, ct, reqText, callback) {
  const url = new URL(urlString);
  if (typeof reqText !== 'string') reqText = `${reqText}`;
  const options = {
    hostname:  url.hostname,
    port:      parseInt(url.port),
    path:      url.pathname,
    method:    'POST',
    headers:   {
      'Content-Type':    ct || 'text/plain',
      'Content-Length':  Buffer.byteLength(reqText),
    },
  };
  const req = http.request(options, (res) => {
    const resultTextChunks = [];
    res.setEncoding('utf8');
    res.on('data', (chunk) => {
      resultTextChunks.push(chunk);
    });
    res.on('end', () => {
      callback({
        received:    true,
        statusCode:  res.statusCode,
        text:        resultTextChunks.join(''),
      });
    });
  });
  req.on('error', (e) => {
    callback({ error: e });
  });
  req.write(reqText);
  req.end();
};


const     retryingPost  =
exports.  retryingPost  =
function  retryingPost  (urlString, ct, reqText, nRetries, callback) {
  const errorsRetried = [];
  const innerCallback = (result) => {
    nRetries--;
    if (result.error && nRetries > 0) {
      errorsRetried.push(result.error);
      basicPost(urlString, ct, reqText, innerCallback);
    } else {
      result.errorsRetried = errorsRetried;
      callback(result);
    }
  };
  return basicPost(urlString, ct, reqText, innerCallback);
};


const     retryingJsonPost  =
exports.  retryingJsonPost  =
function  retryingJsonPost  (urlString, reqObject, nRetries, callback) {
  const reqText = `${JSON.stringify(reqObject, undefined, 2)}\n`;
  const innerCallback = (result) => {
    try {
      result.object = JSON.parse(result.text);
    } catch (jsonParseEx) {
      if (!result.error) result.error = jsonParseEx;
    }
    callback(result);
  };
  return retryingPost(urlString, 'application/json', reqText, nRetries, innerCallback);
};


/*************************************************************\
**                                                           **
**    ====  HTML Generator  ====                             **
**    9/14/2020 AV                                           **
**                                                           **
**    Many times in the past I tried to make this module.    **
**    I think I understand well enough to do so now.         **
**                                                           **
**    Google.com will be the default model,                  **
**    to default to power while avoiding questions.          **
**                                                           **
**    It's not perfect, nor do I intend it to be yet.        **
**                                                           **
\*************************************************************/


const     collapseStr  =
exports.  collapseStr  =
function  collapseStr  (x) {
  return x ? (Array.isArray(x) ? x.map(collapseStr).join('') : '' + x) : '';
};


const     makeHtml  =
exports.  makeHtml  =
function  makeHtml  ({ lang, fixed, title, style, head, body, mainDiv, script }) {

  const bits = [];

  // Just as Google does, I use a lowercase DTD, because in theory it might compress better.
  bits.push('<!doctype html>');

  // Due to unfortunate browser implementation, it turns out lang="en" is the only neutral option,
  // because omitting lang="en" has come to mean "use machine learning to guess a random odd language and apply translation",
  // and the only way to avoid that annoyance is to say lang="en" regardless.
  bits.push(`<html lang="${lang || 'en'}">`);

  // Once again, it might compress better as lowercase.
  bits.push('<meta charset="utf-8">');

  bits.push(`<meta name="viewport" content="width=device-width, initial-scale=1${
    fixed ? ', minimum-scale=1, maximum-scale=1, user-scalable=no' : ''
  }">`);

  if (title) bits.push(`<title>${title}</title>`);

  if (style) {
    if (isObject(style) && style.src) {
      const each = Array.isArray(style.src) ? style.src : [style.src];
      for (let s of each) bits.push(`<link href="${s}" rel="stylesheet">`);
    } else bits.push(`<style>${collapseStr(style)}</style>`);
  }

  if (head) bits.push(collapseStr(head));

  bits.push('</head>');

  bits.push('<body>');

  if (body) bits.push(collapseStr(body));

  if (mainDiv) bits.push(`<div id="main">${collapseStr(mainDiv)}</div>`);

  if (script) {
    if (isObject(script) && script.src) {
      const each = Array.isArray(script.src) ? script.src : [script.src];
      for (let s of each) bits.push(`<script src="${s}"></script>`);
    } else bits.push(`<script>${collapseStr(script)}</script>`);
  }

  bits.push('</body>');

  bits.push('</html>');

  //TODO: Check "viewport". Test every path. Compare with old 'good-request'. Collapse with previous versions of 'makeHtml'.

  return bits.join('');
};


/********************************\
**                              **
**    gss | good-string-sort    **
**                              \********************************************\
**                                                                          **
**  This function correctly sorts strings according to Unicode Codepoints.  **
**  For example:                                                            **
**    ['some', 'strings', 'in here.'].sort(gss);                            **
**                                                                          **
\****************************************************************************/


const     goodStringSort  =
exports.  goodStringSort  =
function  goodStringSort  (a, b) {
  if (!(typeof a === 'string' && typeof b === 'string'))
    throw new Error('good-string-sort: Expects a pair of string arguments.');
  const codepointsA = [...a].map((c) => c.codePointAt());
  const codepointsB = [...b].map((c) => c.codePointAt());
  // Note that the length of the codepoint-arrays DIFFERS from the length of the raw strings due to SURROGATE PAIRS.
  const l = Math.max(codepointsA.length, codepointsB.length);
  for (let i = 0; i < l; i++) {
    let sortCharA = codepointsA[i]; if (sortCharA === undefined) sortCharA = -1;
    let sortCharB = codepointsB[i]; if (sortCharB === undefined) sortCharB = -1;
    if       (sortCharA > sortCharB)  return 1;
    else if  (sortCharA < sortCharB)  return -1;
  }
  return 0;
};