PG upgrade procedure + test disk space

CHANGELOG.md

@@ -1,5 +1,6 @@
 # Changelog Fab Manager
 
+- Upgraded PostgreSQL from 9.4 to 11
 - Optional reCaptcha checkbox in sign-up form
 - Ability to configure and export the accounting data to the ACD accounting software
 - Compute the VAT per item in each invoices, instead of globally
@@ -14,6 +15,7 @@
 - Fix a bug: create a plan does not set its name
 - Fix a bug: unable to dissociate the last machine from a formation
 - Fix a security issue: fixed [CVE-2015-9284](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-9284)
+- [TODO DEPLOY] **IMPORTANT** Please read [postgres_upgrade.md](doc/postgres_upgrade.md) for instructions on upgrading PostgreSQL. 
 - [TODO DEPLOY] `rake db:migrate`
 - [TODO DEPLOY] -> (only dev) `yarn install` and `bundle install`
 - [TODO DEPLOY] -> (only dev) configure `DEFAULT_HOST: 'localhost:5000'` and `DEFAULT_PROTOCOL: http` in [application.yml](config/application.yml.default)

doc/elastic_upgrade.md

@@ -10,7 +10,7 @@ We've wrote a script to automate the process while keeping your data integrity,
   Usually, `apt update && apt install curl jq sudo gawk`, ran as root, will do the trick but this may change, depending upon your system.
 - You'll need at least 4GB of RAM for the data migration to complete successfully.
   The script will try to add 4GB of swap memory if this requirement is detected as missing but this will consume you hard disk space (see below).
-- 1,17GB of free disk space are also required to perform the data migration.
+- 1,2GB of free disk space are also required to perform the data migration.
   Please ensure that you'll have enough space, considering the point above. The script won't run otherwise.
 - This script will run on any Linux or Macintoch systems if you installed ElasticSearch using docker or docker-compose.
   Otherwise, only Debian compatible OS (like Ubuntu) and MacOS X are supported for classical installations. On any other cases you'll need to perform the upgrade yourself manually.

doc/postgres_upgrade.md

@@ -0,0 +1,28 @@
+# Instructions for upgrading PostgreSQL
+
+## Automatic upgrade
+
+Fab-manager release 4.2.0 has upgraded its dependency to PostgreSQL from version 9.4 to version 11 as the previous won't be maintained from from february 2020.
+To keep using fab-manager you need to upgrade your installation with the new version.
+We've wrote a script to automate the process while keeping your data integrity, but there's some requirements to understand before running it.
+
+- You need to install *curl* and *GNU awk* on your system before running the script. 
+  Usually, `apt update && apt install curl gawk`, ran as root, will do the trick but this may change, depending upon your system.
+- A bit of free disk space is also required to perform the data migration. 
+  The amount needed depends on your current database size, the script will check it and tell you if there's not enough available space.
+- This script should run on any Linux or MacOS systems if you installed ElasticSearch using docker-compose.
+  Otherwise, you must perform the upgrade yourself manually.
+
+Once you've understood all the points above, you can run the migration script with the following:
+
+```bash
+cd /apps/fabmanager
+# do not run as root, elevation will be prompted if needed
+\curl \sSL https://raw.githubusercontent.com/sleede/fab-manager/master/scripts/postgre-upgrade.sh | bash
+```
+
+## Manual upgrade
+
+For instructions regarding a manual upgrade, please refer to the official documentation:
+
+- https://www.postgresql.org/docs/11/upgrading.html

scripts/postgre-upgrade.sh

@@ -19,14 +19,6 @@ config()
   read -rp "Is fab-manager installed at \"$FM_PATH\"? (y/N) " confirm </dev/tty
   if [ "$confirm" = "y" ]
   then
-    # checking disk space (minimum required = 1168323KB)
-    space=$(df $FM_PATH | awk '/[0-9]%/{print $(NF-2)}')
-    if [ "$space" -lt 1258291 ]
-    then
-      echo "Not enough free disk space to perform upgrade. Please free at least 1,2GB of disk space and try again"
-      df -h $FM_PATH
-      exit 7
-    fi
     if [ -f "$FM_PATH/config/application.yml" ]
     then
       PG_HOST=$(cat "$FM_PATH/config/application.yml" | grep POSTGRES_HOST | awk '{print $2}')
@@ -50,6 +42,19 @@ config()
   fi
 }
 
+test_free_space()
+{
+  # checking disk space (minimum required = 1.2GB)
+  required=$(du -d 0 "$PG_PATH" | awk '{ print $1 }')
+  space=$(df $FM_PATH | awk '/[0-9]%/{print $(NF-2)}')
+  if [ "$space" -lt "$required" ]
+  then
+    echo "Not enough free disk space to perform upgrade. Please free at least $required bytes of disk space and try again"
+    df -h $FM_PATH
+    exit 7
+  fi
+}
+
 test_docker_compose()
 {
   if [[ -f "$FM_PATH/docker-compose.yml" ]]
@@ -126,6 +131,7 @@ upgrade_postgres()
     OLD='9.4'
     NEW='11'
     read_path
+    test_free_space
     prepare_path
     pg_upgrade
     upgrade_compose