From 33d7d4b312de92539c40c174a7debb08fb076c34 Mon Sep 17 00:00:00 2001
From: Jimmy Monin <jimmy@monin.net>
Date: Sun, 1 Jul 2018 10:06:14 +0200
Subject: [PATCH] Use Redis helper to use an available database during
 installation

---
 scripts/_common.sh | 42 ++++++++++++++++++++++++++++++++++++++++++
 scripts/install    |  5 +++++
 scripts/remove     |  7 +++++++
 scripts/upgrade    |  4 ++++
 4 files changed, 58 insertions(+)

diff --git a/scripts/_common.sh b/scripts/_common.sh
index 517a1f9..75a06dd 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -651,3 +651,45 @@ ynh_maintenance_mode_OFF () {
 
 	systemctl reload nginx
 }
+
+#=================================================
+# REDIS HELPERS
+#=================================================
+
+# get the first available redis database
+#
+# usage: ynh_redis_get_free_db
+# | returns: the database number to use
+ynh_redis_get_free_db() {
+	local result max db
+	result="$(redis-cli INFO keyspace)"
+
+	# get the num
+	max=$(cat /etc/redis/redis.conf | grep ^databases | grep -Eow "[0-9]+")
+
+	db=0
+	# default Debian setting is 15 databases
+	for i in $(seq 0 "$max")
+	do
+	 	if ! echo "$result" | grep -q "db$i"
+	 	then
+			db=$i
+	 		break 1
+ 		fi
+ 		db=-1
+	done
+
+	test "$db" -eq -1 && ynh_die "No available Redis databases..."
+
+	echo "$db"
+}
+
+# Create a master password and set up global settings
+# Please always call this script in install and restore scripts
+#
+# usage: ynh_redis_remove_db database
+# | arg: database - the database to erase
+ynh_redis_remove_db() {
+	local db=$1
+	redis-cli -n "$db" flushall
+}
diff --git a/scripts/install b/scripts/install
index e8ffd05..aa89932 100644
--- a/scripts/install
+++ b/scripts/install
@@ -148,6 +148,11 @@ ynh_replace_string "smtp_address =" "smtp_address = localhost" "$discourse_confi
 ynh_replace_string "smtp_domain =" "smtp_domain = $domain" "$discourse_config_file"
 ynh_replace_string "smtp_enable_start_tls = true" "smtp_enable_start_tls = false" "$discourse_config_file"
 
+# Configure redis
+redis_db=$(ynh_redis_get_free_db)
+ynh_app_setting_set "$app" redis_db "$redis_db"
+ynh_replace_string "redis_db = 0" "redis_db = $redis_db" "$discourse_config_file"
+
 # Calculate and store the config file checksum
 ynh_store_file_checksum "$discourse_config_file"
 
diff --git a/scripts/remove b/scripts/remove
index f9584da..732c003 100644
--- a/scripts/remove
+++ b/scripts/remove
@@ -18,6 +18,7 @@ app=$YNH_APP_INSTANCE_NAME
 domain=$(ynh_app_setting_get $app domain)
 db_name=$(ynh_app_setting_get $app db_name)
 final_path=$(ynh_app_setting_get $app final_path)
+redis_db=$(ynh_app_setting_get $app redis_db)
 
 #=================================================
 # STANDARD REMOVE
@@ -56,6 +57,12 @@ ynh_remove_ruby
 
 ynh_psql_remove_db $db_name $db_name
 
+#=================================================
+# REMOVE THE REDIS DATABASE
+#=================================================
+
+ynh_redis_remove_db "$redis_db"
+
 #=================================================
 # REMOVE APP MAIN DIR
 #=================================================
diff --git a/scripts/upgrade b/scripts/upgrade
index 1041e13..d5ecf77 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -34,6 +34,7 @@ is_public=$(ynh_app_setting_get $app is_public)
 admin=$(ynh_app_setting_get $app admin)
 db_name=$(ynh_app_setting_get $app db_name)
 db_pwd=$(ynh_app_setting_get $app db_pwd)
+redis_db=$(ynh_app_setting_get $app redis_db)
 
 # Check memory requirements
 check_memory_requirements_upgrade
@@ -130,6 +131,9 @@ if ! ynh_is_upstream_up_to_date ; then
 	ynh_replace_string "smtp_domain =" "smtp_domain = $domain" "$discourse_config_file"
 	ynh_replace_string "smtp_enable_start_tls = true" "smtp_enable_start_tls = false" "$discourse_config_file"
 
+	# Configure redis
+	ynh_replace_string "redis_db = 0" "redis_db = $redis_db" "$discourse_config_file"
+
 	# Calculate and store the config file checksum
 	ynh_store_file_checksum "$discourse_config_file"