diff --git a/data/helpers.d/psql b/data/helpers.d/psql
index 2ef13482a..f0be628ea 100644
--- a/data/helpers.d/psql
+++ b/data/helpers.d/psql
@@ -1,21 +1,261 @@
+#!/bin/bash
+
+PSQL_ROOT_PWD_FILE=/etc/yunohost/psql
+
+# Open a connection as a user
+#
+# example: ynh_psql_connect_as 'user' 'pass' <<< "UPDATE ...;"
+# example: ynh_psql_connect_as 'user' 'pass' < /path/to/file.sql
+#
+# usage: ynh_psql_connect_as --user=user --password=password [--database=database]
+# | arg: -u, --user - the user name to connect as
+# | arg: -p, --password - the user password
+# | arg: -d, --database - the database to connect to
+ynh_psql_connect_as() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=upd
+	declare -Ar args_array=([u]=user= [p]=password= [d]=database=)
+	local user
+	local password
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+	database="${database:-}"
+
+	sudo --login --user=postgres PGUSER="$user" PGPASSWORD="$password" psql "$database"
+}
+
+# Execute a command as root user
+#
+# usage: ynh_psql_execute_as_root --sql=sql [--database=database]
+# | arg: -s, --sql - the SQL command to execute
+# | arg: -d, --database - the database to connect to
+ynh_psql_execute_as_root() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=sd
+	declare -Ar args_array=([s]=sql= [d]=database=)
+	local sql
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+	database="${database:-}"
+
+	ynh_psql_connect_as --user="postgres" --password="$(sudo cat $PSQL_ROOT_PWD_FILE)" \
+		--database="$database" <<<"$sql"
+}
+
+# Execute a command from a file as root user
+#
+# usage: ynh_psql_execute_file_as_root --file=file [--database=database]
+# | arg: -f, --file - the file containing SQL commands
+# | arg: -d, --database - the database to connect to
+ynh_psql_execute_file_as_root() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=fd
+	declare -Ar args_array=([f]=file= [d]=database=)
+	local file
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+	database="${database:-}"
+
+	ynh_psql_connect_as --user="postgres" --password="$(sudo cat $PSQL_ROOT_PWD_FILE)" \
+		--database="$database" <"$file"
+}
+
+# Create a database and grant optionnaly privilegies to a user
+#
+# [internal]
+#
+# usage: ynh_psql_create_db db [user]
+# | arg: db - the database name to create
+# | arg: user - the user to grant privilegies
+ynh_psql_create_db() {
+	local db=$1
+	local user=${2:-}
+
+	local sql="CREATE DATABASE ${db};"
+
+	# grant all privilegies to user
+	if [ -n "$user" ]; then
+		sql+="GRANT ALL PRIVILEGES ON DATABASE ${db} TO ${user} WITH GRANT OPTION;"
+	fi
+
+	ynh_psql_execute_as_root --sql="$sql"
+}
+
+# Drop a database
+#
+# [internal]
+#
+# If you intend to drop the database *and* the associated user,
+# consider using ynh_psql_remove_db instead.
+#
+# usage: ynh_psql_drop_db db
+# | arg: db - the database name to drop
+ynh_psql_drop_db() {
+	local db=$1
+	sudo --login --user=postgres dropdb $db
+}
+
+# Dump a database
+#
+# example: ynh_psql_dump_db 'roundcube' > ./dump.sql
+#
+# usage: ynh_psql_dump_db --database=database
+# | arg: -d, --database - the database name to dump
+# | ret: the psqldump output
+ynh_psql_dump_db() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=d
+	declare -Ar args_array=([d]=database=)
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	sudo --login --user=postgres pg_dump "$database"
+}
+
+# Create a user
+#
+# [internal]
+#
+# usage: ynh_psql_create_user user pwd
+# | arg: user - the user name to create
+# | arg: pwd - the password to identify user by
+ynh_psql_create_user() {
+	local user=$1
+	local pwd=$2
+	ynh_psql_execute_as_root --sql="CREATE USER $user WITH ENCRYPTED PASSWORD '$pwd'"
+}
+
+# Check if a psql user exists
+#
+# usage: ynh_psql_user_exists --user=user
+# | arg: -u, --user - the user for which to check existence
+ynh_psql_user_exists() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=u
+	declare -Ar args_array=([u]=user=)
+	local user
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	if ! sudo --login --user=postgres PGUSER="postgres" PGPASSWORD="$(sudo cat $PSQL_ROOT_PWD_FILE)" psql -tAc "SELECT rolname FROM pg_roles WHERE rolname='$user';" | grep --quiet "$user" ; then
+		return 1
+	else
+		return 0
+	fi
+}
+
+# Check if a psql database exists
+#
+# usage: ynh_psql_database_exists --database=database
+# | arg: -d, --database - the database for which to check existence
+ynh_psql_database_exists() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=d
+	declare -Ar args_array=([d]=database=)
+	local database
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	if ! sudo --login --user=postgres PGUSER="postgres" PGPASSWORD="$(sudo cat $PSQL_ROOT_PWD_FILE)" psql -tAc "SELECT datname FROM pg_database WHERE datname='$database';" | grep --quiet "$user"; then
+		return 1
+	else
+		return 0
+	fi
+}
+
+# Drop a user
+#
+# [internal]
+#
+# usage: ynh_psql_drop_user user
+# | arg: user - the user name to drop
+ynh_psql_drop_user() {
+	ynh_psql_execute_as_root --sql="DROP USER ${1};"
+}
+
+# Create a database, an user and its password. Then store the password in the app's config
+#
+# After executing this helper, the password of the created database will be available in $db_pwd
+# It will also be stored as "psqlpwd" into the app settings.
+#
+# usage: ynh_psql_setup_db --db_user=user --db_name=name [--db_pwd=pwd]
+# | arg: -u, --db_user - Owner of the database
+# | arg: -n, --db_name - Name of the database
+# | arg: -p, --db_pwd - Password of the database. If not given, a password will be generated
+ynh_psql_setup_db() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=unp
+	declare -Ar args_array=([u]=db_user= [n]=db_name= [p]=db_pwd=)
+	local db_user
+	local db_name
+	db_pwd=""
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	local new_db_pwd=$(ynh_string_random) # Generate a random password
+	# If $db_pwd is not given, use new_db_pwd instead for db_pwd
+	db_pwd="${db_pwd:-$new_db_pwd}"
+
+	if ! ynh_psql_user_exists --user=$db_user; then
+		ynh_psql_create_user "$db_user" "$db_pwd"
+	fi
+
+	ynh_psql_create_db "$db_name" "$db_user"                     # Create the database
+	ynh_app_setting_set --app=$app --key=psqlpwd --value=$db_pwd # Store the password in the app's config
+}
+
+# Remove a database if it exists, and the associated user
+#
+# usage: ynh_psql_remove_db --db_user=user --db_name=name
+# | arg: -u, --db_user - Owner of the database
+# | arg: -n, --db_name - Name of the database
+ynh_psql_remove_db() {
+	# Declare an array to define the options of this helper.
+	local legacy_args=un
+	declare -Ar args_array=([u]=db_user= [n]=db_name=)
+	local db_user
+	local db_name
+	# Manage arguments with getopts
+	ynh_handle_getopts_args "$@"
+
+	local psql_root_password=$(sudo cat $PSQL_ROOT_PWD_FILE)
+	if ynh_psql_database_exists --database=$db_name; then # Check if the database exists
+		echo "Removing database $db_name" >&2
+		ynh_psql_drop_db $db_name # Remove the database
+	else
+		echo "Database $db_name not found" >&2
+	fi
+
+	# Remove psql user if it exists
+	if ynh_psql_user_exists --user=$db_user; then
+		echo "Removing user $db_user" >&2
+		ynh_psql_drop_user $db_user
+	else
+		echo "User $db_user not found" >&2
+	fi
+}
+
 # Create a master password and set up global settings
 # Please always call this script in install and restore scripts
 #
 # usage: ynh_psql_test_if_first_run
 ynh_psql_test_if_first_run() {
-	if [ -f /etc/yunohost/psql ];
-	then
+	if [ -f "$PSQL_ROOT_PWD_FILE" ]; then
 		echo "PostgreSQL is already installed, no need to create master password"
 	else
 		local pgsql="$(ynh_string_random)"
-		echo "$pgsql" > /etc/yunohost/psql
+		echo "$pgsql" >/etc/yunohost/psql
 
-		if [ -e /etc/postgresql/9.4/ ]
-		then
+		if [ -e /etc/postgresql/9.4/ ]; then
 			local pg_hba=/etc/postgresql/9.4/main/pg_hba.conf
-		elif [ -e /etc/postgresql/9.6/ ]
-		then
+			local logfile=/var/log/postgresql/postgresql-9.4-main.log
+		elif [ -e /etc/postgresql/9.6/ ]; then
 			local pg_hba=/etc/postgresql/9.6/main/pg_hba.conf
+			local logfile=/var/log/postgresql/postgresql-9.6-main.log
 		else
 			ynh_die "postgresql shoud be 9.4 or 9.6"
 		fi
@@ -27,122 +267,12 @@ ynh_psql_test_if_first_run() {
 		# https://www.postgresql.org/docs/current/static/auth-pg-hba-conf.html#EXAMPLE-PG-HBA.CONF
 		# Note: we can't use peer since YunoHost create users with nologin
 		#  See: https://github.com/YunoHost/yunohost/blob/unstable/data/helpers.d/user
-		sed -i '/local\s*all\s*all\s*peer/i \
-			local all all password' "$pg_hba"
+		ynh_replace_string --match_string="local\(\s*\)all\(\s*\)all\(\s*\)peer" --replace_string="local\1all\2all\3password" --target_file="$pg_hba"
+
+		# Advertise service in admin panel
+		yunohost service add postgresql --log "$logfile"
+
 		systemctl enable postgresql
 		systemctl reload postgresql
 	fi
 }
-
-# Open a connection as a user
-#
-# example: ynh_psql_connect_as 'user' 'pass' <<< "UPDATE ...;"
-# example: ynh_psql_connect_as 'user' 'pass' < /path/to/file.sql
-#
-# usage: ynh_psql_connect_as user pwd [db]
-# | arg: user - the user name to connect as
-# | arg: pwd - the user password
-# | arg: db - the database to connect to
-ynh_psql_connect_as() {
-	local user="$1"
-	local pwd="$2"
-	local db="$3"
-	sudo --login --user=postgres PGUSER="$user" PGPASSWORD="$pwd" psql "$db"
-}
-
-# # Execute a command as root user
-#
-# usage: ynh_psql_execute_as_root sql [db]
-# | arg: sql - the SQL command to execute
-ynh_psql_execute_as_root () {
-	local sql="$1"
-	sudo --login --user=postgres psql <<< "$sql"
-}
-
-# Execute a command from a file as root user
-#
-# usage: ynh_psql_execute_file_as_root file [db]
-# | arg: file - the file containing SQL commands
-# | arg: db - the database to connect to
-ynh_psql_execute_file_as_root() {
-	local file="$1"
-	local db="$2"
-	sudo --login --user=postgres psql "$db" < "$file"
-}
-
-# Create a database, an user and its password. Then store the password in the app's config
-#
-# After executing this helper, the password of the created database will be available in $db_pwd
-# It will also be stored as "psqlpwd" into the app settings.
-#
-# usage: ynh_psql_setup_db user name [pwd]
-# | arg: user - Owner of the database
-# | arg: name - Name of the database
-# | arg: pwd - Password of the database. If not given, a password will be generated
-ynh_psql_setup_db () {
-	local db_user="$1"
-	local db_name="$2"
-	local new_db_pwd=$(ynh_string_random)	# Generate a random password
-	# If $3 is not given, use new_db_pwd instead for db_pwd.
-	local db_pwd="${3:-$new_db_pwd}"
-	ynh_psql_create_db "$db_name" "$db_user" "$db_pwd"	# Create the database
-	ynh_app_setting_set "$app" psqlpwd "$db_pwd"	# Store the password in the app's config
-}
-
-# Create a database and grant privilegies to a user
-#
-# usage: ynh_psql_create_db db [user [pwd]]
-# | arg: db - the database name to create
-# | arg: user - the user to grant privilegies
-# | arg: pwd  - the user password
-ynh_psql_create_db() {
-	local db="$1"
-	local user="$2"
-	local pwd="$3"
-	ynh_psql_create_user "$user" "$pwd"
-	sudo --login --user=postgres createdb --owner="$user" "$db"
-}
-
-# Drop a database
-#
-# usage: ynh_psql_drop_db db
-# | arg: db - the database name to drop
-# | arg: user - the user to drop
-ynh_psql_remove_db() {
-	local db="$1"
-	local user="$2"
-	sudo --login --user=postgres dropdb "$db"
-	ynh_psql_drop_user "$user"
-}
-
-# Dump a database
-#
-# example: ynh_psql_dump_db 'roundcube' > ./dump.sql
-#
-# usage: ynh_psql_dump_db db
-# | arg: db - the database name to dump
-# | ret: the psqldump output
-ynh_psql_dump_db() {
-	local db="$1"
-	sudo --login --user=postgres pg_dump "$db"
-}
-
-
-# Create a user
-#
-# usage: ynh_psql_create_user user pwd [host]
-# | arg: user - the user name to create
-ynh_psql_create_user() {
-	local user="$1"
-	local pwd="$2"
-	sudo --login --user=postgres psql -c"CREATE USER $user WITH PASSWORD '$pwd'" postgres
-}
-
-# Drop a user
-#
-# usage: ynh_psql_drop_user user
-# | arg: user - the user name to drop
-ynh_psql_drop_user() {
-	local user="$1"
-	sudo --login --user=postgres dropuser "$user"
-}