Personal blog written from scratch using Node.js, Bootstrap, and MySQL. https://jrtechs.net
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

264 lines
8.9 KiB

  1. const pandoc = require('node-pandoc');
  2. const utils = require('../utils/utils.js');
  3. const sql = require('../utils/sql');
  4. const argsFull = '--from markdown-markdown_in_html_blocks+raw_html --toc --toc-depth=3 -N --mathjax -t html5';
  5. const argsPreview = '--mathjax -t html5';
  6. module.exports=
  7. {
  8. /**
  9. * Renders the entire blog post based on the sql data pulled
  10. * from the database.
  11. *
  12. * @param post sql data which has title, date, and header img location
  13. * @param blocks number of blocks to display for a preview or -1 for
  14. * all the blocks
  15. * @returns {Promise} async call which renders the entire blog post.
  16. */
  17. generateBlogPost: function(post, blocks)
  18. {
  19. return new Promise(function(resolve, reject)
  20. {
  21. Promise.all([module.exports.generateBlogPostHeader(post),
  22. module.exports.generateBlogPostBody(post, blocks)])
  23. .then(function()
  24. {
  25. resolve(post);
  26. }).catch(function(error)
  27. {
  28. reject(error);
  29. })
  30. });
  31. },
  32. /**
  33. * Renders the header of the blog post which contains the header image, and date
  34. * published.
  35. *
  36. * @param post sql data
  37. * @returns {string}
  38. */
  39. generateBlogPostHeader: function(post)
  40. {
  41. if(post.picture_url !== "n/a")
  42. post.hasPicture = true;
  43. post.published = post.published.toDateString();
  44. return;
  45. },
  46. /**
  47. * Method which renders the body of the blog post. This is responsible for getting
  48. * the contents of the markdown/latex file and rendering it into beautiful html.
  49. *
  50. * @param post stuff from the SQL table
  51. * @param blocks
  52. * @returns {Promise}
  53. */
  54. generateBlogPostBody: function(post, blocks)
  55. {
  56. return new Promise(function(resolve, reject)
  57. {
  58. sql.getCategory(post.category_id).then(function(category)
  59. {
  60. module.exports.generateBlogPostComponent(category[0].url, post.url, blocks).then(function(html)
  61. {
  62. post.categoryURL = category[0].url;
  63. post.blogBody = html;
  64. resolve();
  65. });
  66. });
  67. })
  68. },
  69. /**
  70. * Decomposition from Generate Blog Post used for the
  71. * blog previewer.
  72. *
  73. * @param categoryURL
  74. * @param postURL
  75. * @param blocks
  76. * @returns {Promise}
  77. */
  78. generateBlogPostComponent: function(categoryURL, postURL, blocks)
  79. {
  80. return new Promise(function(resolve, reject)
  81. {
  82. const pathName = "blogContent/posts/" + categoryURL + "/"
  83. + postURL + ".md";
  84. var markDown = utils.getFileContents(pathName).toString();
  85. markDown = markDown.split("(media/").join("(" + "../blogContent/posts/"
  86. + categoryURL + "/media/");
  87. module.exports.convertToHTML(markDown, blocks).then(function(result)
  88. {
  89. result = result.split("<figcaption>").join("<figcaption style=\"visibility: hidden;\">");
  90. //this line prevents older versions of pandoc from including invalid cdm scripts
  91. result = result.split("<script src=\"https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS_CHTML-full\" type=\"text/javascript\"></script>").join("");
  92. result = result.split("<script src=\"https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML\" type=\"text/javascript\"></script>").join("");
  93. //stuff for youtube videos
  94. var re = /\<youtube .*?>/;
  95. //<youtube src="" />
  96. while (result.search(re) != -1)
  97. {
  98. var ytid = result.substring(result.search(re) + 14, result.search(re)+ 11 + 14);
  99. var youtubeHTML = "<div class=\"wrapper\">\n" +
  100. "\t<div class=\"youtube\" data-embed=\"" +
  101. ytid +
  102. "\" />\n" +
  103. "\t\t<div class=\"play-button\"></div>\n" +
  104. "\t</div>\n" +
  105. "</div>\n";
  106. var original = "<youtube src=\"" + ytid + "\" />";
  107. result = result.split(original).join(youtubeHTML);
  108. }
  109. var regExp = /\<customHTML .*?>/;
  110. while (result.search(regExp) != -1)
  111. {
  112. const pathName = "blogContent/posts/" + categoryURL + "/html/"
  113. + postURL + ".html";
  114. var htmlContent = utils.getFileContents(pathName).toString();
  115. result = result.split("<customHTML />").join(htmlContent);
  116. }
  117. if(blocks == -1)
  118. resolve(result);
  119. const htmlBlocks = result.split("<p>");
  120. var html = "";
  121. for(var i = 0; i < blocks; i++)
  122. {
  123. html += "<p>" + htmlBlocks[i];
  124. }
  125. resolve(html);
  126. }).catch(function(error)
  127. {
  128. reject(error);
  129. })
  130. })
  131. },
  132. /**
  133. * Converts markdown into html.
  134. *
  135. * @param markdownContents
  136. * @param type
  137. * @returns {Promise}
  138. */
  139. convertToHTML: function(markdownContents, type)
  140. {
  141. if(type == -1)
  142. {
  143. return module.exports.pandocWrapper(markdownContents, argsFull);
  144. }
  145. else
  146. {
  147. return module.exports.pandocWrapper(markdownContents, argsFull);
  148. }
  149. },
  150. pandocWrapper: function(markdownContents, pandocArgs)
  151. {
  152. return new Promise((resolve, reject)=>
  153. {
  154. // Set your callback function
  155. callback = function (err, html)
  156. {
  157. if (err)
  158. {
  159. reject(err);
  160. }
  161. if(html === undefined)
  162. {
  163. resolve("");
  164. }
  165. else
  166. {
  167. html = html.split("<img").join("<img style=\"max-width: 100%;\" ");
  168. html = html.split("<code>").join("<code class='hljs cpp'>");
  169. resolve(html);
  170. }
  171. };
  172. pandoc(markdownContents, pandocArgs, callback);
  173. });
  174. },
  175. /**
  176. * Renders a bunch of blog post previews to the user
  177. *
  178. * @param baseURL-- url of the page
  179. * @param posts -- sql data about the blog to render
  180. * @param currentPage -- the current page to render
  181. * @param numOfPosts -- number of blog to render
  182. * @returns {Promise} renders the html of the blog
  183. */
  184. renderBatchOfPosts: function(baseURL, posts, currentPage, numOfPosts, templateContext)
  185. {
  186. if(typeof currentPage == "undefined")
  187. {
  188. currentPage = 1;
  189. }
  190. else
  191. {
  192. currentPage = Number(currentPage);
  193. }
  194. return new Promise(function(resolve, reject)
  195. {
  196. const promises = [];
  197. for(var i = (currentPage-1) * numOfPosts; i < (currentPage-1) * numOfPosts + numOfPosts; i++)
  198. {
  199. if(i < posts.length)
  200. {
  201. promises.push(new Promise(function(res, rej)
  202. {
  203. if(posts.length != 1)
  204. {
  205. templateContext.preview = true
  206. }
  207. module.exports.generateBlogPost(posts[i], posts.length === 1 ? -1: 3).then(function(tempContext)
  208. {
  209. res(tempContext);
  210. }).catch(function(error)
  211. {
  212. rej();
  213. })
  214. }));
  215. }
  216. }
  217. Promise.all(promises).then(function(posts)
  218. {
  219. templateContext.posts = posts;
  220. resolve();
  221. }).catch(function(error)
  222. {
  223. reject(error);
  224. });
  225. });
  226. }
  227. };