Merge branch 'feature/warn-init' into 'main'

Warn if re-initialising the same database

Closes #177

See merge request !122

cmd/dmd/cmd/db_init.go

 package cmd
 
 import (
+	"context"
 	"database/sql"
 	"fmt"
+	"os"
 
 	"dmd.tanna.dev/internal/metadata/db"
 	"dmd.tanna.dev/internal/repositories"
@@ -14,6 +16,8 @@ var dbInitCmd = &cobra.Command{
 	Short: "Initialise the local database",
 	Long:  `Initialise the local database before importing data into it.`,
 	Run: func(cmd *cobra.Command, args []string) {
+		warnIfDatabaseExists(cmd.Context(), databasePath)
+
 		sqlDB, err := sql.Open("sqlite", databasePath)
 		cobra.CheckErr(err)
 
@@ -31,3 +35,22 @@ var dbInitCmd = &cobra.Command{
 func init() {
 	dbCmd.AddCommand(dbInitCmd)
 }
+
+func warnIfDatabaseExists(ctx context.Context, databasePath string) {
+	if _, err := os.Stat(databasePath); err != nil {
+		return
+	}
+
+	sqlDB, err := sql.Open("sqlite", databasePath)
+	if err != nil {
+		return
+	}
+
+	metadata := db.New(sqlDB)
+	m, err := metadata.RetrieveDMDVersion(ctx)
+	if err == nil {
+		logger.Warn(fmt.Sprintf("The database %s has already been initialised, so re-initialising it may not work, as `dmd` does not perform migrations", databasePath), "dmdVersion", m.Value)
+	} else {
+		logger.Warn(fmt.Sprintf("The file %s already exists, so re-initialising it may not work, as `dmd` does not perform migrations", databasePath))
+	}
+}