added nixos modules to perform simple backup scheduling for directories, postgresql and mysql database dumps

svn path=/nixos/trunk/; revision=17690

modules/module-list.nix

@@ -36,6 +36,9 @@
   ./security/sudo.nix
   ./services/audio/alsa.nix
   ./services/audio/pulseaudio.nix
+  ./services/backup/mysql-backup.nix
+  ./services/backup/postgresql-backup.nix
+  ./services/backup/sitecopy-backup.nix
   ./services/databases/mysql.nix
   ./services/databases/postgresql.nix
   ./services/hardware/acpid.nix

modules/services/backup/mysql-backup.nix

@@ -0,0 +1,71 @@
+{pkgs, config, ...}:
+
+let
+  inherit (pkgs.lib) mkOption mkIf singleton concatStrings;
+  inherit (pkgs) mysql gzip;
+
+  location = config.services.mysqlBackup.location ;
+
+  mysqlBackupCron = db : ''
+    ${config.services.mysqlBackup.period} mysql ${mysql}/bin/mysqldump ${db} | ${gzip}/bin/gzip -c > ${location}/${db}.gz
+  ''; 
+
+in
+
+{
+
+  ###### interface
+  
+  options = {
+  
+    services.mysqlBackup = {
+
+      enable = mkOption {
+        default = false;
+        description = ''
+          Whether to enable MySQL backups.
+        '';
+      };
+
+      period = mkOption {
+        default = "15 01 * * *";
+        description = ''
+          This option defines (in the format used by cron) when the
+          databases should be dumped.
+          The default is to update at 01:15 (at night) every day.
+        '';
+      };
+
+      databases = mkOption {
+        default = [];
+        description = ''
+          List of database names to dump.
+        '';
+      };
+ 
+      location = mkOption {
+        default = "/var/backup/mysql";
+        description = ''
+          Location to put the gzipped PostgreSQL database dumps.
+        '';
+      };
+    };
+
+  };
+
+  ###### implementation
+  config = mkIf config.services.mysqlBackup.enable {
+    services.cron = {
+      systemCronJobs = 
+        pkgs.lib.optional
+          config.services.mysqlBackup.enable
+          (concatStrings (map mysqlBackupCron config.services.mysqlBackup.databases));
+    };
+
+    system.activationScripts.mysqlBackup = pkgs.stringsWithDeps.noDepEntry ''
+         mkdir -m 0700 -p ${config.services.mysqlBackup.location}
+         chown mysql ${config.services.mysqlBackup.location}
+    '';
+  };
+  
+}

modules/services/backup/postgresql-backup.nix

@@ -0,0 +1,71 @@
+{pkgs, config, ...}:
+
+let
+  inherit (pkgs.lib) mkOption mkIf singleton concatStrings;
+  inherit (pkgs) postgresql gzip;
+
+  location = config.services.postgresqlBackup.location ;
+
+  postgresqlBackupCron = db : ''
+    ${config.services.postgresqlBackup.period} root ${postgresql}/bin/pg_dump ${db} | ${gzip}/bin/gzip -c > ${location}/${db}.gz
+  ''; 
+
+in
+
+{
+
+  ###### interface
+  
+  options = {
+  
+    services.postgresqlBackup = {
+
+      enable = mkOption {
+        default = false;
+        description = ''
+          Whether to enable PostgreSQL dumps.
+        '';
+      };
+
+      period = mkOption {
+        default = "15 01 * * *";
+        description = ''
+          This option defines (in the format used by cron) when the
+          databases should be dumped.
+          The default is to update at 01:15 (at night) every day.
+        '';
+      };
+
+      databases = mkOption {
+        default = [];
+        description = ''
+          List of database names to dump. 
+        '';
+      };
+ 
+      location = mkOption {
+        default = "/var/backup/postgresql";
+        description = ''
+          Location to put the gzipped PostgreSQL database dumps.
+        '';
+      };
+    };
+
+  };
+
+  ###### implementation
+  config = mkIf config.services.postgresqlBackup.enable {
+    services.cron = {
+      systemCronJobs = 
+        pkgs.lib.optional
+          config.services.postgresqlBackup.enable
+          (concatStrings (map postgresqlBackupCron config.services.postgresqlBackup.databases));
+    };
+
+    system.activationScripts.postgresqlBackup = pkgs.stringsWithDeps.noDepEntry ''
+         mkdir -m 0700 -p ${config.services.postgresqlBackup.location}
+         chown root ${config.services.postgresqlBackup.location}
+    '';
+  };
+  
+}

modules/services/backup/sitecopy-backup.nix

@@ -0,0 +1,109 @@
+{pkgs, config, ...}:
+
+let
+  inherit (pkgs.lib) mkOption mkIf singleton concatStrings;
+  inherit (pkgs) sitecopy;
+
+  stateDir = "/var/spool/sitecopy";
+
+  sitecopyCron = backup : ''
+    ${if backup ? period then backup.period else config.services.sitecopy.period} root ${sitecopy}/bin/sitecopy --storepath=${stateDir} --rcfile=${stateDir}/${backup.name}.conf --update ${backup.name}
+  ''; 
+in
+
+{
+
+  ###### interface
+  
+  options = {
+  
+    services.sitecopy = {
+
+      enable = mkOption {
+        default = false;
+        description = ''
+          Whether to enable sitecopy backups of specified directories.
+        '';
+      };
+
+      period = mkOption {
+        default = "15 04 * * *";
+        description = ''
+          This option defines (in the format used by cron) when the
+          sitecopy backup are being run.
+          The default is to update at 04:15 (at night) every day.
+        '';
+      };
+
+      backups = mkOption {
+        default = [];
+        description = ''
+           List of attributesets describing the backups. 
+           E.g. { name = "test"; 
+                  local = "/tmp/backup"; 
+                  remote = "/staff-groups/ewi/st/strategoxt/backup/test";
+                  server = "webdata.tudelft.nl";
+                  protocol = "webdav";
+                  https = true ;
+                };
+           Username/password are extracted from ${stateDir}/sitecopy.secrets at activation 
+           time. The secrets file lines should have the following structure:
+
+             <server> <username> <password>
+ 
+        '';
+      }; 
+
+    };
+
+  };
+
+
+  ###### implementation
+
+  config = mkIf config.services.sitecopy.enable {
+    environment.systemPackages = [ sitecopy ];
+
+    services.cron = {
+      systemCronJobs = pkgs.lib.optional
+          config.services.sitecopy.enable
+          (concatStrings (map sitecopyCron config.services.sitecopy.backups));
+    };
+
+
+    system.activationScripts.postgresqlBackup = 
+      pkgs.stringsWithDeps.noDepEntry ''  
+          mkdir -m 0700 -p ${stateDir}
+          chown root ${stateDir}
+          touch ${stateDir}/sitecopy.secrets
+          chown root ${stateDir}/sitecopy.secrets
+
+          ${pkgs.lib.concatStrings (map ( b: ''
+              unset secrets
+              unset secret
+              secrets=`grep '^${b.server}' ${stateDir}/sitecopy.secrets | head -1`
+              secret=($secrets)
+              cat > ${stateDir}/${b.name}.conf << EOF
+                site ${b.name}
+                server ${b.server}
+                protocol ${b.protocol}
+                username ''${secret[1]}
+                password ''${secret[2]}
+                local ${b.local}
+                remote ${b.remote}
+                ${if b.https then "http secure" else ""}
+              EOF
+              chmod 0600 ${stateDir}/${b.name}.conf
+              if ! test -e ${stateDir}/${b.name} ; then
+                echo " * Initializing sitecopy '${b.name}'"
+                ${sitecopy}/bin/sitecopy --storepath=${stateDir} --rcfile=${stateDir}/${b.name}.conf --initialize ${b.name}
+              else
+                echo " * Sitecopy '${b.name}' already initialized"
+              fi
+            '' ) config.services.sitecopy.backups 
+         )}
+
+      '';
+  };
+  
+}