fixed some issues with postgresql logs when using NFS for synced folders

CHANGELOG.md

 Upcoming version:
 -----------------
+  - fixed some issues with postgresql logs when using NFS for synced folders (Nikolaus Krismer)
   - using owner/group name for postgresql logs (Nikolaus Krismer)
   - changed hostname retrieval function (Nikolaus Krismer)
   - choosing vagrant provider depending on host (in gradle; not only in vagrantfile) (Nikolaus Krismer)

Vagrantfile

@@ -50,6 +50,11 @@ else
   vname="isochrone-local"
 end
 
+$db_restart = <<SCRIPT
+  echo Restarting postgresql database...
+  systemctl restart postgresql-9.6
+SCRIPT
+
 Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
   config.vm.boot_timeout = 600
   config.vm.box = vbox
@@ -87,13 +92,17 @@ Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
   config.vm.synced_folder "conf", "/setup/conf"
   config.vm.synced_folder "data", "/opt/data", create: true
   config.vm.synced_folder "img", "/setup/img"
-  config.vm.synced_folder "log/postgresql", "/var/log/postgresql", create: true, owner: "postgres", group: "postgres"
+  # settings owner/group to postgres (using uid/gid, since on first provision (before installing postgresql) username is not known and only hard-coding the id works)
+  config.vm.synced_folder "log/postgresql", "/var/log/postgresql", create: true, owner: "26", group: "26"
   config.vm.synced_folder "log/bootstrap", "/var/log/vagrant_bootstrap", create: true, owner: "vagrant", group: "vagrant"
 
   # Setup environment on startup (done using a shell script)
   config.vm.provision "shell", keep_color: true, path: "bootstrap/prepareEnvironment.sh", args: ["secretPhdPassword#2014!", (isLocalDeploy ? "true" : "false"), (isJenkinsDeploy ? "true" : "false")]
   config.vm.provision "shell", keep_color: true, path: "bootstrap/createDatabase.sh", args: ["niko", "secretPhdPassword#2014!"]
   config.vm.provision "shell", keep_color: true, path: "bootstrap/importData.sh", args: ["niko", "secretPhdPassword#2014!", (deployAllDatasets ? "true" : "false")]
+  # workaround to allow putting the postgresql log file into synced_folder when using NFS (e.g: when using vagrant-libvirt)
+  # a restart after all NFS shares have been mounted will allow the creation of the log files (when the DB is started before the mounting has been finished, permission will be denied)
+  config.vm.provision "shell", inline: $db_restart, run: "always"
   # Optionally activate database logging (for queryTimeLogging this is done in the testcase itself now)
   #config.vm.provision "shell", path: "bootstrap/activateDatabaseLogging.sh"