ADD: added function to update db scheme automaticly

2025-11-18 22:23:08 +01:00
parent ef396af480
commit 3818fbf460
15 changed files with 876 additions and 186 deletions
--- a/backend/internal/database/migrateScheme.go
+++ b/backend/internal/database/migrateScheme.go
@@ -0,0 +1,188 @@
+package database
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+	"reflect"
+	"strings"
+)
+
+// Auto-create table, columns, types, indexes for PostgreSQL
+func CreateOrUpdateTablePG(db *sql.DB, table string, model interface{}) error {
+	// 0) Check if table exists
+	exists, err := tableExists(db, table)
+	if err != nil {
+		return err
+	}
+
+	if !exists {
+		// Create table from model
+		if err := createTable(db, table, model); err != nil {
+			return err
+		}
+		return nil
+	}
+
+	// Update table if it exists
+	return alterTable(db, table, model)
+}
+
+func tableExists(db *sql.DB, table string) (bool, error) {
+	query := `SELECT EXISTS (SELECT FROM information_schema.tables WHERE table_name=$1);`
+	var exists bool
+	err := db.QueryRow(query, table).Scan(&exists)
+	return exists, err
+}
+
+func createTable(db *sql.DB, table string, model interface{}) error {
+	t := reflect.TypeOf(model)
+	if t.Kind() != reflect.Struct {
+		return fmt.Errorf("model must be a struct")
+	}
+
+	cols := []string{}
+	idx := []string{}
+
+	for i := 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+
+		// ignore fields not meant for DB
+		if f.Tag.Get("ignore") == "true" || f.Tag.Get("db") == "-" {
+			continue
+		}
+
+		col := f.Tag.Get("db")
+		if col == "" {
+			col = strings.ToLower(f.Name)
+		}
+		sqlType := f.Tag.Get("sql")
+		if sqlType == "" {
+			return fmt.Errorf("field '%s' missing sql tag", f.Name)
+		}
+
+		cols = append(cols, fmt.Sprintf("\"%s\" %s", col, sqlType))
+
+		if f.Tag.Get("index") == "true" {
+			idx = append(idx, col)
+		}
+	}
+
+	query := fmt.Sprintf(`CREATE TABLE "%s" (%s);`, table, strings.Join(cols, ", "))
+	log.Println("[CREATE TABLE]", query)
+
+	if _, err := db.Exec(query); err != nil {
+		return err
+	}
+
+	// Create indexes
+	for _, col := range idx {
+		indexName := fmt.Sprintf("%s_%s_idx", table, col)
+		iq := fmt.Sprintf(`CREATE INDEX "%s" ON "%s" ("%s");`, indexName, table, col)
+		log.Println("[CREATE INDEX]", iq)
+		if _, err := db.Exec(iq); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func alterTable(db *sql.DB, table string, model interface{}) error {
+	currentCols, err := getColumnsPG(db, table)
+	if err != nil {
+		return err
+	}
+
+	currentIdx, err := getIndexesPG(db, table)
+	if err != nil {
+		return err
+	}
+
+	t := reflect.TypeOf(model)
+
+	for i := 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+		col := f.Tag.Get("db")
+		if col == "" {
+			col = strings.ToLower(f.Name)
+		}
+		sqlType := f.Tag.Get("sql")
+
+		// Missing column
+		if _, ok := currentCols[col]; !ok {
+			query := fmt.Sprintf(`ALTER TABLE "%s" ADD COLUMN "%s" %s;`, table, col, sqlType)
+			log.Println("[ADD COLUMN]", query)
+			if _, err := db.Exec(query); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// Type mismatch → alter
+		pgType := strings.ToLower(currentCols[col])
+		expType := strings.ToLower(sqlType)
+
+		if !strings.Contains(pgType, strings.Split(expType, "(")[0]) {
+			query := fmt.Sprintf(`ALTER TABLE "%s" ALTER COLUMN "%s" TYPE %s;`, table, col, sqlType)
+			log.Println("[ALTER TYPE]", query)
+			if _, err := db.Exec(query); err != nil {
+				return err
+			}
+		}
+
+		// Indexing
+		if f.Tag.Get("index") == "true" {
+			idxName := fmt.Sprintf("%s_%s_idx", table, col)
+
+			if !currentIdx[idxName] {
+				iq := fmt.Sprintf(`CREATE INDEX "%s" ON "%s" ("%s");`, idxName, table, col)
+				log.Println("[CREATE INDEX]", iq)
+				if _, err := db.Exec(iq); err != nil {
+					return err
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+// Helpers
+func getColumnsPG(db *sql.DB, table string) (map[string]string, error) {
+	q := `SELECT column_name, data_type FROM information_schema.columns WHERE table_name=$1;`
+	rows, err := db.Query(q, table)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	cols := map[string]string{}
+	for rows.Next() {
+		var name, dtype string
+		if err := rows.Scan(&name, &dtype); err != nil {
+			return nil, err
+		}
+		cols[name] = dtype
+	}
+	return cols, nil
+}
+
+func getIndexesPG(db *sql.DB, table string) (map[string]bool, error) {
+	q := `SELECT indexname FROM pg_indexes WHERE tablename=$1;`
+	rows, err := db.Query(q, table)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	idx := map[string]bool{}
+	for rows.Next() {
+		var i string
+		if err := rows.Scan(&i); err != nil {
+			return nil, err
+		}
+		idx[i] = true
+	}
+	return idx, nil
+}