Added support for initial data loading when using badger db

internal/datastore/badger_datastore/badger_datastore.go

@@ -1,9 +1,13 @@
 package badgerdatastore
 
 import (
+	"encoding/json"
+	"log"
+	"os"
 	"time"
 
 	"github.com/dgraph-io/badger/v4"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/logger"
 )
 
@@ -13,6 +17,7 @@ type BadgerDataStore struct {
 }
 
 type BadgerDataStoreOptions struct {
+	InitialDataFilePath string
 	PersistDataFilePath string
 }
 
@@ -35,6 +40,8 @@ func NewBadgerDataStore(options BadgerDataStoreOptions) *BadgerDataStore {
 		gcTicker: gcTicker,
 	}
 
+	ds.initializeDataStore(options.InitialDataFilePath)
+
 	go ds.runGarbageCollector()
 
 	return ds
@@ -64,3 +71,53 @@ func (r *BadgerDataStore) runGarbageCollector() {
 		}
 	}
 }
+
+func (r *BadgerDataStore) initializeDataStore(initialDataFilePath string) {
+	if initialDataFilePath == "" {
+		return
+	}
+
+	stat, err := os.Stat(initialDataFilePath)
+	if err != nil {
+		panic(err)
+	}
+
+	if stat.IsDir() {
+		logger.ErrorLn("Argument '-Persist' must be a path to file, not a directory.")
+		os.Exit(1)
+	}
+
+	jsonData, err := os.ReadFile(initialDataFilePath)
+	if err != nil {
+		log.Fatalf("Error reading state JSON file: %v", err)
+		return
+	}
+
+	var state datastore.InitialDataModel
+	if err := json.Unmarshal([]byte(jsonData), &state); err != nil {
+		log.Fatalf("Error parsing state JSON file: %v", err)
+		return
+	}
+
+	for dbName, dbModel := range state.Databases {
+		r.CreateDatabase(dbModel)
+		for colName, colModel := range state.Collections[dbName] {
+			r.CreateCollection(dbName, colModel)
+			for _, docModel := range state.Documents[dbName][colName] {
+				r.CreateDocument(dbName, colName, docModel)
+			}
+
+			for _, triggerModel := range state.Triggers[dbName][colName] {
+				r.CreateTrigger(dbName, colName, triggerModel)
+			}
+
+			for _, spModel := range state.StoredProcedures[dbName][colName] {
+				r.CreateStoredProcedure(dbName, colName, spModel)
+			}
+
+			for _, udfModel := range state.UserDefinedFunctions[dbName][colName] {
+				r.CreateUserDefinedFunction(dbName, colName, udfModel)
+			}
+		}
+	}
+}