Merge pull request #43 from clj-codes/feat/google-analytics

feat: google analytics

Author: rafaeldelboni

shadow-cljs.edn

@@ -16,7 +16,8 @@
                                    :install-deps true
                                    :closure-defines {codes.clj.docs.frontend.config/BASE_URL #shadow/env ["BASE_URL"]
                                                      codes.clj.docs.frontend.config/CLIENT_ID #shadow/env ["CLIENT_ID"]
-                                                     codes.clj.docs.frontend.config/REDIRECT_URI #shadow/env ["REDIRECT_URI"]}}
+                                                     codes.clj.docs.frontend.config/REDIRECT_URI #shadow/env ["REDIRECT_URI"]
+                                                     codes.clj.docs.frontend.config/GA_TAG_ID #shadow/env ["GA_TAG_ID"]}}
                 :build-hooks      [(codes.clj.docs.frontend.dev.shadow.hooks/hashed-files
                                     ["resources/public/css/app.css"
                                      "resources/public/js/core.js"])

src/codes/clj/docs/frontend/config.cljs

@@ -20,10 +20,14 @@
 (goog-define BASE_URL "https://docs-backend.fly.dev/api/")
 (goog-define CLIENT_ID "46d86692f00ed9c613a1")
 (goog-define REDIRECT_URI "https://docs.clj.codes/github-callback")
+(goog-define GA_TAG_ID "")
 
 (def config
   (let [debug? goog.DEBUG]
     {:debug? debug?
+     :ga-tag-id (if debug?
+                  ""
+                  GA_TAG_ID)
      :base-url (if debug?
                  "http://localhost:3001/api/"
                  BASE_URL)

src/codes/clj/docs/frontend/core.cljs

@@ -2,6 +2,7 @@
   (:require ["@mantine/core" :refer [MantineProvider]]
             ["react-dom/client" :as rdom]
             [codes.clj.docs.frontend.config :refer [theme]]
+            [codes.clj.docs.frontend.infra.analytics :refer [google-analytics]]
             [codes.clj.docs.frontend.infra.flex.hook :refer [use-flex]]
             [codes.clj.docs.frontend.infra.helix :refer [defnc]]
             [codes.clj.docs.frontend.infra.routes.core :refer [init-routes!]]
@@ -25,5 +26,6 @@
   (.render root ($ app)))
 
 (defn ^:export init []
+  (google-analytics)
   (init-routes!)
   (render))

src/codes/clj/docs/frontend/infra/analytics.cljs

@@ -0,0 +1,31 @@
+(ns codes.clj.docs.frontend.infra.analytics
+  (:require [clojure.string :as string]
+            [codes.clj.docs.frontend.infra.system.state :as system.state]))
+
+(defn google-tag-manager
+  [ga-tag-id]
+  (let [script (js/document.createElement "script")]
+    (set! (.-src script) (str "https://www.googletagmanager.com/gtag/js?id="
+                              ga-tag-id))
+    (set! (.-async script) true)
+    (js/document.head.prepend script)
+    script))
+
+(defn google-tag
+  [ga-tag-id gtm-script]
+  (let [script (js/document.createElement "script")]
+    (set! (.-src script) (str "window.dataLayer = window.dataLayer || [];
+                               function gtag(){dataLayer.push(arguments);}
+                               gtag('js', new Date());
+
+                               gtag('config', '" ga-tag-id "');"))
+    (js/document.head.insertBefore script (.-nextSibling gtm-script))))
+
+(defn ga-scripts
+  [ga-tag-id]
+  (when-not (string/blank? ga-tag-id)
+    (let [gtm-script (google-tag-manager ga-tag-id)]
+      (google-tag ga-tag-id gtm-script))))
+
+(defn google-analytics []
+  (ga-scripts (-> @system.state/components :config :ga-tag-id)))

test/codes/clj/docs/frontend/test/infra/analytics_test.cljs

@@ -0,0 +1,13 @@
+(ns codes.clj.docs.frontend.test.infra.analytics-test
+  (:require [cljs.test :refer-macros [deftest is testing]]
+            [clojure.string :as string]
+            [codes.clj.docs.frontend.infra.analytics :as analytics]))
+
+(deftest ga-scripts-test
+  (testing "not-blank GA_TAG_ID should return a script containing the tag id"
+    (let [ga-tag-id "G-0123456789"
+          ga-scripts (analytics/ga-scripts ga-tag-id)]
+      (is (instance? js/HTMLScriptElement ga-scripts))
+      (is (string/includes? (.-src ga-scripts) ga-tag-id))))
+  (testing "blank GA_TAG_ID should not return anything"
+    (is (nil? (analytics/ga-scripts "")))))