Add shareable URLs in the guide

lib/url.js

@@ -0,0 +1,50 @@
+import queryString from 'query-string';
+import siteConfig from 'data/site';
+
+export const prefixHost = (url) => {
+  return /^\//.test(url) ? `${siteConfig.url}${url}` : url;
+};
+
+export const getTwitterUrl = (username) => {
+  return `https://twitter.com/${username}`;
+};
+
+export const getTwitterShareUrl = ({ text, url }) => {
+  const urlToShare = `${prefixHost(url)}?${queryString.stringify({
+    utm_source: 'roadmap.sh',
+    utm_campaign: 'share',
+    utm_medium: 'twitter',
+  })}`;
+
+  return `https://twitter.com/intent/tweet?text=${text}&url=${encodeURI(urlToShare)}`;
+};
+
+export const getFacebookShareUrl = ({ text, url }) => {
+  const urlToShare = `${prefixHost(url)}?${queryString.stringify({
+    utm_source: 'roadmap.sh',
+    utm_campaign: 'share',
+    utm_medium: 'facebook',
+  })}`;
+
+  return `https://www.facebook.com/sharer/sharer.php?quote=${text}&u=${encodeURI(urlToShare)}`;
+};
+
+export const getRedditShareUrl = ({ text, url }) => {
+  const urlToShare = `${prefixHost(url)}?${queryString.stringify({
+    utm_source: 'roadmap.sh',
+    utm_campaign: 'share',
+    utm_medium: 'reddit'
+  })}`;
+
+  return `https://www.reddit.com/submit?title=${text}&url=${encodeURI(urlToShare)}`;
+};
+
+export const getHnShareUrl = ({ text, url }) => {
+  const urlToShare = `${prefixHost(url)}?${queryString.stringify({
+    utm_source: 'roadmap.sh',
+    utm_campaign: 'share',
+    utm_medium: 'hn'
+  })}`;
+
+  return `https://news.ycombinator.com/submitlink?t=${text}&u=${urlToShare}`;
+};