Added state perstistance

- Define new state directory to hold the last dns update config and push it into the config, default to state/
- Refactoring, move updaterequest into service and out of webapp. Keep only the form parsing there. Specifically, move the processing code into the service package, it shouldn't be in the webapp.
- Add code to load and save the last updaterequest into a state file (watch out to keep the possibly unhashed password out of it).
- Add a command line option to load all available state files given the current configured user list from the command line.
- Refactor user configuartion loading to separate it from user authentication, claen up the code.
- We now require the username in the config, to make handling it in state updates easier. This will allow easier transition to DB style storage anyway.
- Update .gitignore

cmd/load-state.go

@@ -0,0 +1,68 @@
+package cmd
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"path"
+
+	"gitea.nehmer.net/torben/dyndns/service"
+	"github.com/spf13/cobra"
+)
+
+var cmdLoadState = &cobra.Command{
+	Use:   "load-state",
+	Short: "Load all state files and process them",
+	Long: `Loads the state files of all present users and reprocesses them. Use this after
+for example a firewall restart or when dyndns data gets lost. It will recreate all
+neccessary NFT set and DNS entries based on the last known state.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		service.LoadConfig()
+		if err := loadAndProcessAllStates(); err != nil {
+			log.Fatalf("Failed to load states: %s", err)
+		}
+		log.Println("State processing successful.")
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(cmdLoadState)
+}
+
+func loadAndProcessAllStates() error {
+	files, err := ioutil.ReadDir(service.C.Users.ConfigDir)
+	if err != nil {
+		return fmt.Errorf("failed to list config directory %s: %v",
+			service.C.Users.ConfigDir, err)
+	}
+
+	for _, file := range files {
+		configFile := path.Join(service.C.Users.ConfigDir, file.Name())
+		uc, err := service.LoadConfigFile(configFile)
+		if err != nil {
+			return fmt.Errorf("failed to load config file %s: %v", configFile, err)
+		}
+
+		stateFile := uc.GetStateFileName()
+		if _, err := os.Stat(stateFile); err != nil {
+			log.Printf("No state file for user %s, skipping (%v)", configFile, err)
+			continue
+		}
+
+		ur, err := service.LoadStateFile(uc)
+		if err != nil {
+			return fmt.Errorf("failed to load sate file %s for user %s: %v",
+				stateFile, uc.UserName, err)
+		}
+
+		log.Printf("Loaded state file %s:\n%v", stateFile, ur.PrettyPrint())
+
+		if err = ur.Process(); err != nil {
+			return fmt.Errorf("failed to process state file %s for user %s: %v",
+				stateFile, uc.UserName, err)
+		}
+	}
+
+	return nil
+}