From e2f400472fd6576064be1035f50c8596f03a3b55 Mon Sep 17 00:00:00 2001
From: Jean-Philippe Evrard <open-source@a.spamming.party>
Date: Tue, 19 Jan 2021 10:46:53 +0100
Subject: [PATCH] Template google analytics data

Without this patch, the index.html contains google analytics at
all times, including for people self-hosting it.

This is a problem for privacy reasons, and only people wanting
to have analytics on their instances should be able to enable
them.

This fixes it by making sure the index.html page is templated
to sideload content from ANALYTICS_CODE_PATH (which itself is
also templated, for convenience).
---
 front/.gitignore                           |  3 ++-
 front/Dockerfile                           |  1 +
 front/dist/ga.html.tmpl                    |  9 ++++++++
 front/dist/{index.html => index.html.tmpl} | 11 ++-------
 front/templater.sh                         | 26 ++++++++++++++++++++++
 5 files changed, 40 insertions(+), 10 deletions(-)
 create mode 100644 front/dist/ga.html.tmpl
 rename front/dist/{index.html => index.html.tmpl} (95%)
 create mode 100755 front/templater.sh

diff --git a/front/.gitignore b/front/.gitignore
index e77b54d0..b6f01e2c 100644
--- a/front/.gitignore
+++ b/front/.gitignore
@@ -5,4 +5,5 @@
 /dist/webpack.config.js
 /dist/webpack.config.js.map
 /dist/src
-*.sh
\ No newline at end of file
+*.sh
+!templater.sh
diff --git a/front/Dockerfile b/front/Dockerfile
index 6c79ad6e..b0d17877 100644
--- a/front/Dockerfile
+++ b/front/Dockerfile
@@ -11,5 +11,6 @@ COPY --from=builder --chown=docker:docker /var/www/messages/generated /var/www/h
 RUN yarn install
 
 ENV NODE_ENV=production
+ENV STARTUP_COMMAND_0="./templater.sh"
 ENV STARTUP_COMMAND_1="yarn run build"
 ENV APACHE_DOCUMENT_ROOT=dist/
diff --git a/front/dist/ga.html.tmpl b/front/dist/ga.html.tmpl
new file mode 100644
index 00000000..ace84b39
--- /dev/null
+++ b/front/dist/ga.html.tmpl
@@ -0,0 +1,9 @@
+<!-- Global site tag (gtag.js) - Google Analytics -->
+<script async src="https://www.googletagmanager.com/gtag/js?id=<!-- TRACKING NUMBER -->"></script>
+<script>
+    window.dataLayer = window.dataLayer || [];
+    function gtag(){dataLayer.push(arguments);}
+    gtag('js', new Date());
+
+    gtag('config', '<!-- TRACKING NUMBER -->');
+</script>
diff --git a/front/dist/index.html b/front/dist/index.html.tmpl
similarity index 95%
rename from front/dist/index.html
rename to front/dist/index.html.tmpl
index 9a197822..a2b44788 100644
--- a/front/dist/index.html
+++ b/front/dist/index.html.tmpl
@@ -6,15 +6,8 @@
               content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
         <meta http-equiv="X-UA-Compatible" content="ie=edge">
 
-        <!-- Global site tag (gtag.js) - Google Analytics -->
-        <script async src="https://www.googletagmanager.com/gtag/js?id=UA-10196481-11"></script>
-        <script>
-            window.dataLayer = window.dataLayer || [];
-            function gtag(){dataLayer.push(arguments);}
-            gtag('js', new Date());
-
-            gtag('config', 'UA-10196481-11');
-        </script>
+        <!-- TRACK CODE -->
+        <!-- END TRACK CODE -->
 
         <link rel="apple-touch-icon" sizes="57x57" href="static/images/favicons/apple-icon-57x57.png">
         <link rel="apple-touch-icon" sizes="60x60" href="static/images/favicons/apple-icon-60x60.png">
diff --git a/front/templater.sh b/front/templater.sh
new file mode 100755
index 00000000..aa6534b3
--- /dev/null
+++ b/front/templater.sh
@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+set -x
+set -o nounset errexit
+template_file_index=dist/index.html.tmpl
+generated_file_index=dist/index.html
+tmp_trackcodefile=/tmp/trackcode
+
+# To inject tracking code, you have two choices:
+# 1) Template using the provided google analytics
+# 2) Insert with your own provided code, by overriding the ANALYTICS_CODE_PATH
+# The ANALYTICS_CODE_PATH is the location of a file inside the container
+ANALYTICS_CODE_PATH="${ANALYTICS_CODE_PATH:-dist/ga.html.tmpl}"
+
+if [[ "${INSERT_ANALYTICS:-NO}" == "NO" ]]; then
+    echo "" > "${tmp_trackcodefile}"
+fi
+
+# Automatically insert analytics if TRACKING_NUMBER is set
+if [[ "${TRACKING_NUMBER:-}" != ""  || "${INSERT_ANALYTICS:-NO}" != "NO" ]]; then
+    echo "Templating code from ${ANALYTICS_CODE_PATH}"
+    sed "s#<!-- TRACKING NUMBER -->#${TRACKING_NUMBER:-}#g" "${ANALYTICS_CODE_PATH}" > "$tmp_trackcodefile"
+fi
+
+echo "Templating ${generated_file_index} from ${template_file_index}"
+sed "/<!-- TRACK CODE -->/r ${tmp_trackcodefile}" "${template_file_index}" > "${generated_file_index}"
+rm "${tmp_trackcodefile}"