From 1af4f366ca0bb3860a18b8435dad8a23d5ea7b62 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=C3=B6rg=20Thalheim?= Date: Sat, 19 Jan 2019 10:33:20 +0000 Subject: [PATCH] nixos/postgresqlBackup: add backupAll option For large setups it is useful to list all databases explicit (for example if temporary databases are also present) and store them in extra files. For smaller setups it is more convenient to just backup all databases at once, because it is easy to forget to update configuration when adding/renaming databases. pg_dumpall also has the advantage that it backups users/passwords. As a result the module becomes easier to use because it is sufficient in the default case to just set one option (services.postgresqlBackup.enable). --- .../services/backup/postgresql-backup.nix | 51 +++++++++++++++---- nixos/tests/postgresql.nix | 27 +++++++--- 2 files changed, 59 insertions(+), 19 deletions(-) diff --git a/nixos/modules/services/backup/postgresql-backup.nix b/nixos/modules/services/backup/postgresql-backup.nix index f9f9568faa5c..11efa47ec5b2 100644 --- a/nixos/modules/services/backup/postgresql-backup.nix +++ b/nixos/modules/services/backup/postgresql-backup.nix @@ -6,11 +6,11 @@ let cfg = config.services.postgresqlBackup; - postgresqlBackupService = db : + postgresqlBackupService = db: dumpCmd: { enable = true; - description = "Backup of database ${db}"; + description = "Backup of ${db} database(s)"; requires = [ "postgresql.service" ]; @@ -26,7 +26,7 @@ let ${pkgs.coreutils}/bin/mv ${cfg.location}/${db}.sql.gz ${cfg.location}/${db}.prev.sql.gz fi - ${config.services.postgresql.package}/bin/pg_dump ${cfg.pgdumpOptions} ${db} | \ + ${dumpCmd} | \ ${pkgs.gzip}/bin/gzip -c > ${cfg.location}/${db}.sql.gz ''; @@ -42,9 +42,7 @@ let in { options = { - services.postgresqlBackup = { - enable = mkOption { default = false; description = '' @@ -61,6 +59,19 @@ in { ''; }; + backupAll = mkOption { + default = cfg.databases == []; + defaultText = "services.postgresqlBackup.databases == []"; + type = lib.types.bool; + description = '' + Backup all databases using pg_dumpall. + This option is mutual exclusive to + services.postgresqlBackup.databases. + The resulting backup dump will have the name all.sql.gz. + This option is the default if no databases are specified. + ''; + }; + databases = mkOption { default = []; description = '' @@ -79,18 +90,36 @@ in { type = types.string; default = "-Cbo"; description = '' - Command line options for pg_dump. + Command line options for pg_dump. This options is not used + if config.services.postgresqlBackup.backupAll is enabled. + Note that config.services.postgresqlBackup.backupAll is also active, + when no databases where specified. ''; }; }; }; - config = mkIf config.services.postgresqlBackup.enable { - - systemd.services = listToAttrs (map (db : { + config = mkMerge [ + { + assertions = [{ + assertion = cfg.backupAll -> cfg.databases == []; + message = "config.services.postgresqlBackup.backupAll cannot be used together with config.services.postgresqlBackup.databases"; + }]; + } + (mkIf (cfg.enable && cfg.backupAll) { + systemd.services.postgresqlBackup = + postgresqlBackupService "all" "${config.services.postgresql.package}/bin/pg_dumpall"; + }) + (mkIf (cfg.enable && !cfg.backupAll) { + systemd.services = listToAttrs (map (db: + let + cmd = "${config.services.postgresql.package}/bin/pg_dump ${cfg.pgdumpOptions} ${db}"; + in { name = "postgresqlBackup-${db}"; - value = postgresqlBackupService db; } ) cfg.databases); - }; + value = postgresqlBackupService db cmd; + }) cfg.databases); + }) + ]; } diff --git a/nixos/tests/postgresql.nix b/nixos/tests/postgresql.nix index 1d434b62a5cb..975ba7f488e2 100644 --- a/nixos/tests/postgresql.nix +++ b/nixos/tests/postgresql.nix @@ -21,7 +21,7 @@ let CREATE TABLE xmltest ( doc xml ); INSERT INTO xmltest (doc) VALUES ('ok'); -- check if libxml2 enabled ''; - make-postgresql-test = postgresql-name: postgresql-package: makeTest { + make-postgresql-test = postgresql-name: postgresql-package: backup-all: makeTest { name = postgresql-name; meta = with pkgs.stdenv.lib.maintainers; { maintainers = [ zagy ]; @@ -29,14 +29,17 @@ let machine = {...}: { - services.postgresql.package=postgresql-package; + services.postgresql.package = postgresql-package; services.postgresql.enable = true; services.postgresqlBackup.enable = true; - services.postgresqlBackup.databases = [ "postgres" ]; + services.postgresqlBackup.databases = optional (!backup-all) "postgres"; }; - testScript = '' + testScript = let + backupName = if backup-all then "all" else "postgres"; + backupService = if backup-all then "postgresqlBackup" else "postgresqlBackup-postgres"; + in '' sub check_count { my ($select, $nlines) = @_; return 'test $(sudo -u postgres psql postgres -tAc "' . $select . '"|wc -l) -eq ' . $nlines; @@ -56,12 +59,20 @@ let $machine->succeed(check_count("SELECT xpath(\'/test/text()\', doc) FROM xmltest;", 1)); # Check backup service - $machine->succeed("systemctl start postgresqlBackup-postgres.service"); - $machine->succeed("zcat /var/backup/postgresql/postgres.sql.gz | grep 'ok'"); - $machine->succeed("stat -c '%a' /var/backup/postgresql/postgres.sql.gz | grep 600"); + $machine->succeed("systemctl start ${backupService}.service"); + $machine->succeed("zcat /var/backup/postgresql/${backupName}.sql.gz | grep 'ok'"); + $machine->succeed("stat -c '%a' /var/backup/postgresql/${backupName}.sql.gz | grep 600"); $machine->shutdown; ''; }; in - mapAttrs' (p-name: p-package: {name=p-name; value=make-postgresql-test p-name p-package;}) postgresql-versions + (mapAttrs' (name: package: { inherit name; value=make-postgresql-test name package false;}) postgresql-versions) // ( + # just pick one version for the dump all test + let + first = head (attrNames postgresql-versions); + name = "${first}-backup-all"; + in { + ${name} = make-postgresql-test name postgresql-versions.${first} true; + } + )