From 132bbcbe0db1ee52227b6d49c195366dce83ac47 Mon Sep 17 00:00:00 2001
From: Mike Cao <mike@mikecao.com>
Date: Mon, 20 Jul 2020 01:54:21 -0700
Subject: [PATCH] Refactored session and collect process.

---
 lib/db.js              |  26 ++---
 lib/session.js         |  49 ++++++++++
 lib/utils.js           |  70 +++-----------
 pages/api/collect.js   |  33 ++++---
 pages/api/session.js   |  51 ----------
 public/umami.js        |   2 +-
 scripts/umami/index.js | 213 ++++++++++++++++++-----------------------
 7 files changed, 192 insertions(+), 252 deletions(-)
 create mode 100644 lib/session.js
 delete mode 100644 pages/api/session.js

diff --git a/lib/db.js b/lib/db.js
index 57518b18..7abbe9df 100644
--- a/lib/db.js
+++ b/lib/db.js
@@ -13,37 +13,39 @@ export async function runQuery(query) {
     });
 }
 
-export async function getWebsite(website_id) {
+export async function getWebsite(website_uuid) {
   return runQuery(
     prisma.website.findOne({
       where: {
-        website_uuid: website_id,
+        website_uuid,
       },
     }),
   );
 }
 
-export async function createSession(website_id, session_id, data) {
-  await runQuery(
+export async function createSession(website_id, data) {
+  return runQuery(
     prisma.session.create({
       data: {
-        session_uuid: session_id,
         website: {
           connect: {
-            website_uuid: website_id,
+            website_id,
           },
         },
         ...data,
       },
+      select: {
+        session_id: true,
+      },
     }),
   );
 }
 
-export async function getSession(session_id) {
+export async function getSession(session_uuid) {
   return runQuery(
     prisma.session.findOne({
       where: {
-        session_uuid: session_id,
+        session_uuid,
       },
     }),
   );
@@ -55,12 +57,12 @@ export async function savePageView(website_id, session_id, url, referrer) {
       data: {
         website: {
           connect: {
-            website_uuid: website_id,
+            website_id,
           },
         },
         session: {
           connect: {
-            session_uuid: session_id,
+            session_id,
           },
         },
         url,
@@ -76,12 +78,12 @@ export async function saveEvent(website_id, session_id, url, event_type, event_v
       data: {
         website: {
           connect: {
-            website_uuid: website_id,
+            website_id,
           },
         },
         session: {
           connect: {
-            session_uuid: session_id,
+            session_id,
           },
         },
         url,
diff --git a/lib/session.js b/lib/session.js
new file mode 100644
index 00000000..daafffd5
--- /dev/null
+++ b/lib/session.js
@@ -0,0 +1,49 @@
+import { getWebsite, getSession, createSession } from 'lib/db';
+import { getCountry, getDevice, getIpAddress, hash, isValidSession } from 'lib/utils';
+
+export default async function checkSession(req) {
+  const { payload } = req.body;
+  const { session } = payload;
+
+  if (isValidSession(session)) {
+    return session;
+  }
+
+  const ip = getIpAddress(req);
+  const { userAgent, browser, os } = getDevice(req);
+  const country = await getCountry(req, ip);
+  const { website: website_uuid, hostname, screen, language } = payload;
+
+  if (website_uuid) {
+    const website = await getWebsite(website_uuid);
+
+    if (website) {
+      const { website_id } = website;
+      const session_uuid = hash(`${website_id}${hostname}${ip}${userAgent}${os}`);
+
+      let session = await getSession(session_uuid);
+
+      if (!session) {
+        session = await createSession(website_id, {
+          session_uuid,
+          hostname,
+          browser,
+          os,
+          screen,
+          language,
+          country,
+        });
+      }
+
+      const { session_id } = session;
+
+      return [
+        website_id,
+        website_uuid,
+        session_id,
+        session_uuid,
+        hash(website_id, website_uuid, session_id, session_uuid),
+      ].join(':');
+    }
+  }
+}
diff --git a/lib/utils.js b/lib/utils.js
index 52f76160..86069443 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -12,8 +12,8 @@ export function md5(s) {
   return crypto.createHash('md5').update(s).digest('hex');
 }
 
-export function hash(s) {
-  return uuid(s, md5(process.env.HASH_SALT));
+export function hash(...args) {
+  return uuid(args.join(''), md5(process.env.HASH_SALT));
 }
 
 export function validHash(s) {
@@ -60,61 +60,19 @@ export async function getCountry(req, ip) {
   return result.country.iso_code;
 }
 
-export async function parseSessionRequest(req) {
-  if (req.method === 'POST') {
-    const ip = getIpAddress(req);
-    const { website_id, hostname, screen, language } = req.body;
-    const { userAgent, browser, os } = getDevice(req);
-    const country = await getCountry(req, ip);
-    const session_id = hash(`${website_id}${hostname}${ip}${userAgent}${os}`);
-
-    return {
-      website_id,
-      session_id,
-      hostname,
-      browser,
-      os,
-      screen,
-      language,
-      country,
-    };
-  }
-
-  return {};
+export function parseSession(session) {
+  const [website_id, website_uuid, session_id, session_uuid, sig] = (session || '').split(':');
+  return {
+    website_id: parseInt(website_id),
+    website_uuid,
+    session_id: parseInt(session_id),
+    session_uuid,
+    sig,
+  };
 }
 
-export function parseCollectRequest(req) {
-  if (req.method === 'POST') {
-    const { type, payload } = req.body;
+export function isValidSession(session) {
+  const { website_id, website_uuid, session_id, session_uuid, sig } = parseSession(session);
 
-    if (payload.session) {
-      const {
-        url,
-        referrer,
-        event_type,
-        event_value,
-        session: { website_id, session_id, time, hash: validationHash },
-      } = payload;
-
-      if (
-        validHash(website_id) &&
-        validHash(session_id) &&
-        validHash(validationHash) &&
-        hash(`${website_id}${session_id}${time}`) === validationHash
-      ) {
-        return {
-          success: 1,
-          type,
-          website_id,
-          session_id,
-          url,
-          referrer,
-          event_type,
-          event_value,
-        };
-      }
-    }
-  }
-
-  return { success: 0 };
+  return hash(website_id, website_uuid, session_id, session_uuid) === sig;
 }
diff --git a/pages/api/collect.js b/pages/api/collect.js
index b1573673..1e12c083 100644
--- a/pages/api/collect.js
+++ b/pages/api/collect.js
@@ -1,25 +1,30 @@
-import { parseCollectRequest } from 'lib/utils';
+import { parseSession } from 'lib/utils';
 import { savePageView, saveEvent } from 'lib/db';
 import { allowPost } from 'lib/middleware';
+import checkSession from 'lib/session';
 
 export default async (req, res) => {
   await allowPost(req, res);
 
-  const values = parseCollectRequest(req);
+  const session = await checkSession(req);
 
-  if (values.success) {
-    const { type, website_id, session_id, url, referrer, event_type, event_value } = values;
+  const { website_id, session_id } = parseSession(session);
+  const { type, payload } = req.body;
+  let ok = 1;
 
-    if (type === 'pageview') {
-      await savePageView(website_id, session_id, url, referrer).catch(() => {
-        values.success = 0;
-      });
-    } else if (type === 'event') {
-      await saveEvent(website_id, session_id, url, event_type, event_value).catch(() => {
-        values.success = 0;
-      });
-    }
+  if (type === 'pageview') {
+    const { url, referrer } = payload;
+    await savePageView(website_id, session_id, url, referrer).catch(e => {
+      ok = 0;
+      throw e;
+    });
+  } else if (type === 'event') {
+    const { url, event_type, event_value } = payload;
+    await saveEvent(website_id, session_id, url, event_type, event_value).catch(() => {
+      ok = 0;
+      throw e;
+    });
   }
 
-  res.status(200).json({ success: values.success });
+  res.status(200).json({ ok, session });
 };
diff --git a/pages/api/session.js b/pages/api/session.js
deleted file mode 100644
index 801dca85..00000000
--- a/pages/api/session.js
+++ /dev/null
@@ -1,51 +0,0 @@
-import { getWebsite, getSession, createSession } from 'lib/db';
-import { hash, parseSessionRequest } from 'lib/utils';
-import { allowPost } from 'lib/middleware';
-
-export default async (req, res) => {
-  await allowPost(req, res);
-
-  let result = { success: 0 };
-
-  const {
-    website_id,
-    session_id,
-    hostname,
-    browser,
-    os,
-    screen,
-    language,
-    country,
-  } = await parseSessionRequest(req);
-
-  if (website_id && session_id) {
-    const website = await getWebsite(website_id);
-
-    if (website) {
-      const session = await getSession(session_id);
-      const time = Date.now();
-
-      if (!session) {
-        await createSession(website_id, session_id, {
-          hostname,
-          browser,
-          os,
-          screen,
-          language,
-          country,
-        });
-      }
-
-      result = {
-        ...result,
-        success: 1,
-        session_id,
-        website_id,
-        time,
-        hash: hash(`${website_id}${session_id}${time}`),
-      };
-    }
-  }
-
-  res.status(200).json(result);
-};
diff --git a/public/umami.js b/public/umami.js
index 492d02aa..d18ffc28 100644
--- a/public/umami.js
+++ b/public/umami.js
@@ -1 +1 @@
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global)return global;throw new Error("unable to locate global object")}();"Promise"in l?l.Promise.prototype["finally"]||(l.Promise.prototype["finally"]=e):l["Promise"]=o,self.fetch||(self.fetch=function(e,t){return t=t||{},new Promise((function(n,r){var o=new XMLHttpRequest,i=[],u=[],s={},a=function(){return{ok:2==(o.status/100|0),statusText:o.statusText,status:o.status,url:o.responseURL,text:function(){return Promise.resolve(o.responseText)},json:function(){return Promise.resolve(JSON.parse(o.responseText))},blob:function(){return Promise.resolve(new Blob([o.response]))},clone:a,headers:{keys:function(){return i},entries:function(){return u},get:function(e){return s[e.toLowerCase()]},has:function(e){return e.toLowerCase()in s}}}};for(var c in o.open(t.method||"get",e,!0),o.onload=function(){o.getAllResponseHeaders().replace(/^(.*?):[^\S\n]*([\s\S]*?)$/gm,(function(e,t,n){i.push(t=t.toLowerCase()),u.push([t,n]),s[t]=s[t]?s[t]+","+n:n})),n(a())},o.onerror=r,o.withCredentials="include"==t.credentials,t.headers)o.setRequestHeader(c,t.headers[c]);o.send(t.body||null)}))}),function(e,t){var n=e.screen,r=n.width,o=n.height,i=e.navigator.language,u=e.location,s=u.hostname,a=u.pathname,c=u.search,f=e.localStorage,l=e.document,h=e.history,p=l.querySelector("script[data-website-id]"),d=p&&p.getAttribute("data-website-id"),v=new URL(p.src).origin,y=r+"x"+o,m=[],w=""+a+c,_=l.referrer,g=function(e,n){var r={session:f.getItem(t),url:w,referrer:_,website:d,hostname:s,screen:y,language:i};return n&&Object.keys(n).forEach((function(e){r[e]=n[e]})),function(e,t){return fetch(e,{method:"post",cache:"no-cache",headers:{Accept:"application/json","Content-Type":"application/json"},body:JSON.stringify(t)}).then((function(e){return e.json()}))}(v+"/api/collect",{type:e,payload:r}).then((function(e){var n=e.ok,r=e.session;return n&&r&&f.setItem(t,r)}))},b=function(){return g("pageview").then((function(){return setTimeout(T,300)}))},j=function(e,t,n){E(),_=w,w=n,b()},P=function(e,t){var n=h[e];return function(e,r,o){var i=[e,r,o];return t.apply(null,i),n.apply(h,i)}};h.pushState=P("pushState",j),h.replaceState=P("replaceState",j);var E=function(){m.forEach((function(e){var t=e[0],n=e[1],r=e[2];t.removeEventListener(n,r,!0)})),m.length=0},T=function(){l.querySelectorAll("[class*='umami--']").forEach((function(e){e.className.split(" ").forEach((function(t){if(/^umami--/.test(t)){var n=t.split("--"),r=n[1],o=n[2];if(r&&o){var i=function(){return g("event",{event_type:r,event_value:o})};m.push([e,r,i]),e.addEventListener(r,i,!0)}}}))}))};b()}(window,"umami.session")}();
diff --git a/scripts/umami/index.js b/scripts/umami/index.js
index 8b91bedd..f27bc032 100644
--- a/scripts/umami/index.js
+++ b/scripts/umami/index.js
@@ -1,134 +1,111 @@
 import 'promise-polyfill/src/polyfill';
 import 'unfetch/polyfill';
 
-const {
-  screen: { width, height },
-  navigator: { language },
-  location: { hostname, pathname, search },
-  localStorage: store,
-  document,
-  history,
-} = window;
+((window, sessionKey) => {
+  const {
+    screen: { width, height },
+    navigator: { language },
+    location: { hostname, pathname, search },
+    localStorage: store,
+    document,
+    history,
+  } = window;
 
-/* Load script */
+  const script = document.querySelector('script[data-website-id]');
+  const website = script && script.getAttribute('data-website-id');
+  const hostUrl = new URL(script.src).origin;
+  const screen = `${width}x${height}`;
+  const listeners = [];
 
-const script = document.querySelector('script[data-website-id]');
+  let currentUrl = `${pathname}${search}`;
+  let currentRef = document.referrer;
 
-if (script) {
-  const website_id = script.getAttribute('data-website-id');
+  /* Helper methods */
 
-  if (website_id) {
-    const sessionKey = 'umami.session';
-    const hostUrl = new URL(script.src).origin;
-    const screen = `${width}x${height}`;
-    let currentUrl = `${pathname}${search}`;
-    let currenrRef = document.referrer;
-    const listeners = [];
+  const post = (url, params) =>
+    fetch(url, {
+      method: 'post',
+      cache: 'no-cache',
+      headers: {
+        Accept: 'application/json',
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify(params),
+    }).then(res => res.json());
 
-    /* Helper methods */
-
-    const post = (url, params) =>
-      fetch(url, {
-        method: 'post',
-        cache: 'no-cache',
-        headers: {
-          Accept: 'application/json',
-          'Content-Type': 'application/json',
-        },
-        body: JSON.stringify(params),
-      }).then(res => res.json());
-
-    const createSession = data =>
-      post(`${hostUrl}/api/session`, data).then(({ success, ...session }) => {
-        if (success) {
-          store.setItem(sessionKey, JSON.stringify(session));
-          return success;
-        }
-      });
-
-    const getSession = () => JSON.parse(store.getItem(sessionKey));
-
-    const getSessionData = url => ({ website_id, hostname, url, screen, language });
-
-    const pageView = (url, referrer) =>
-      post(`${hostUrl}/api/collect`, {
-        type: 'pageview',
-        payload: { url, referrer, session: getSession() },
-      }).then(({ success }) => {
-        if (!success) {
-          store.removeItem(sessionKey);
-        }
-        return success;
-      });
-
-    const trackEvent = (url, event_type, event_value) =>
-      post(`${hostUrl}/api/collect`, {
-        type: 'event',
-        payload: { url, event_type, event_value, session: getSession() },
-      });
-
-    const execute = (url, referrer) => {
-      const data = getSessionData(url);
-
-      if (!store.getItem(sessionKey)) {
-        createSession(data).then(success => success && pageView(url, referrer));
-      } else {
-        pageView(url, referrer).then(
-          success =>
-            !success && createSession(data).then(success => success && pageView(url, referrer)),
-        );
-      }
+  const collect = (type, params) => {
+    const payload = {
+      session: store.getItem(sessionKey),
+      url: currentUrl,
+      referrer: currentRef,
+      website,
+      hostname,
+      screen,
+      language,
     };
 
-    /* Handle push state */
-
-    const handlePush = (state, title, url) => {
-      removeEvents();
-      currenrRef = currentUrl;
-      currentUrl = url;
-      execute(currentUrl, currenrRef);
-      setTimeout(loadEvents, 300);
-    };
-
-    const hook = (type, cb) => {
-      const orig = history[type];
-      return (state, title, url) => {
-        const args = [state, title, url];
-        cb.apply(null, args);
-        return orig.apply(history, args);
-      };
-    };
-
-    history.pushState = hook('pushState', handlePush);
-    history.replaceState = hook('replaceState', handlePush);
-
-    /* Handle events */
-
-    const removeEvents = () => {
-      listeners.forEach(([element, type, listener]) => {
-        element.removeEventListener(type, listener, true);
+    if (params) {
+      Object.keys(params).forEach(key => {
+        payload[key] = params[key];
       });
-      listeners.length = 0;
-    };
+    }
 
-    const loadEvents = () => {
-      document.querySelectorAll("[class*='umami--']").forEach(element => {
-        element.className.split(' ').forEach(className => {
-          if (/^umami--/.test(className)) {
-            const [, type, value] = className.split('--');
-            if (type && value) {
-              const listener = () => trackEvent(currentUrl, type, value);
-              listeners.push([element, type, listener]);
-              element.addEventListener(type, listener, true);
-            }
+    return post(`${hostUrl}/api/collect`, {
+      type,
+      payload,
+    }).then(({ ok, session }) => ok && session && store.setItem(sessionKey, session));
+  };
+
+  const pageView = () => collect('pageview').then(() => setTimeout(loadEvents, 300));
+
+  const pageEvent = (event_type, event_value) => collect('event', { event_type, event_value });
+
+  /* Handle history */
+
+  const handlePush = (state, title, url) => {
+    removeEvents();
+    currentRef = currentUrl;
+    currentUrl = url;
+    pageView();
+  };
+
+  const hook = (type, cb) => {
+    const orig = history[type];
+    return (state, title, url) => {
+      const args = [state, title, url];
+      cb.apply(null, args);
+      return orig.apply(history, args);
+    };
+  };
+
+  history.pushState = hook('pushState', handlePush);
+  history.replaceState = hook('replaceState', handlePush);
+
+  /* Handle events */
+
+  const removeEvents = () => {
+    listeners.forEach(([element, type, listener]) => {
+      element.removeEventListener(type, listener, true);
+    });
+    listeners.length = 0;
+  };
+
+  const loadEvents = () => {
+    document.querySelectorAll("[class*='umami--']").forEach(element => {
+      element.className.split(' ').forEach(className => {
+        if (/^umami--/.test(className)) {
+          const [, type, value] = className.split('--');
+          if (type && value) {
+            const listener = () => pageEvent(type, value);
+            listeners.push([element, type, listener]);
+            element.addEventListener(type, listener, true);
           }
-        });
+        }
       });
-    };
+    });
+  };
 
-    /* Start */
+  /* Start */
 
-    execute(currentUrl, currenrRef);
-    loadEvents();
-  }
-}
+  pageView();
+})(window, 'umami.session');