签入脚本

2026-10-20 11:37:25 +08:00
commit 7f5e8470af
909 changed files with 4045080 additions and 0 deletions
@@ -0,0 +1,244 @@
+package migrate
+
+import (
+	"context"
+	"sort"
+	"strings"
+
+	"github.com/gogf/gf/v2/database/gdb"
+)
+
+// ============================== 源库结构内省 ==============================
+
+// listTables 查询源库表清单
+//
+// 受白名单过滤，按表名排序以保证结果可复现
+func listTables(ctx context.Context, db gdb.DB, whitelist []string) ([]string, error) {
+	tables, err := db.Tables(ctx)
+	if err != nil {
+		return nil, err
+	}
+	if len(whitelist) > 0 {
+		allow := make(map[string]bool, len(whitelist))
+		for _, t := range whitelist {
+			allow[strings.TrimSpace(t)] = true
+		}
+		filtered := make([]string, 0, len(tables))
+		for _, t := range tables {
+			if allow[t] {
+				filtered = append(filtered, t)
+			}
+		}
+		tables = filtered
+	}
+	sort.Strings(tables)
+	return tables, nil
+}
+
+// introspectTable 单表全量内省
+//
+// 采集列信息（含注释、默认值、自增、主键）、二级索引与表注释
+func introspectTable(ctx context.Context, db gdb.DB, dialect, table string) (*TableMeta, error) {
+	fields, err := db.TableFields(ctx, table)
+	if err != nil {
+		return nil, err
+	}
+	meta := &TableMeta{Name: table}
+	// TableFields 返回 map，按 Index 排序还原物理列序
+	sorted := make([]*gdb.TableField, 0, len(fields))
+	for _, f := range fields {
+		sorted = append(sorted, f)
+	}
+	sort.Slice(sorted, func(i, j int) bool { return sorted[i].Index < sorted[j].Index })
+	for _, f := range sorted {
+		typ, length, scale, enumVals := normalizeType(dialect, f.Type)
+		meta.Columns = append(meta.Columns, ColumnMeta{
+			Name:     f.Name,
+			Type:     typ,
+			Length:   length,
+			Scale:    scale,
+			EnumVals: enumVals,
+			Nullable: f.Null,
+			Default:  cleanDefault(dialect, f.Default),
+			AutoInc:  isAutoInc(f.Extra),
+			Comment:  f.Comment,
+			IsPK:     strings.EqualFold(f.Key, "PRI") || strings.EqualFold(f.Key, "pri"),
+		})
+	}
+	// 索引与表注释（方言相关）
+	switch dialect {
+	case "mysql":
+		if err = introspectIndexesMySQL(ctx, db, table, meta); err != nil {
+			return nil, err
+		}
+		meta.Comment = tableCommentMySQL(ctx, db, table)
+	case "pgsql":
+		if err = introspectIndexesPgsql(ctx, db, table, meta); err != nil {
+			return nil, err
+		}
+		meta.Comment = tableCommentPgsql(ctx, db, table)
+	default:
+		// 其余方言：主键经列元数据已识别，二级索引降级跳过（首期实测链路 mysql→pgsql）
+	}
+	// 统一索引命名（迁移后全库一种规则，见 normalizeIndexName）
+	normalizeIndexes(meta)
+	return meta, nil
+}
+
+// normalizeIndexes 归一化二级索引名
+//
+// 主键随建表落地，不包含在索引集合中
+func normalizeIndexes(meta *TableMeta) {
+	for i := range meta.Indexes {
+		idx := &meta.Indexes[i]
+		idx.Name = normalizeIndexName(meta.Name, idx.Unique, idx.Columns)
+	}
+}
+
+// normalizeIndexName 统一索引命名
+//
+// 唯一索引使用 uk_ 前缀，普通索引使用 idx_ 前缀，后接表名与列名；
+// 名称超过 63 字符时截断，兼容多数数据库的索引名长度上限
+func normalizeIndexName(table string, unique bool, cols []string) string {
+	prefix := "idx"
+	if unique {
+		prefix = "uk"
+	}
+	name := prefix + "_" + table + "_" + strings.Join(cols, "_")
+	if len(name) > 63 {
+		name = name[:63]
+	}
+	return name
+}
+
+// isAutoInc 判断是否自增列
+//
+// 兼容 MySQL 的 auto_increment 以及 PostgreSQL、SQL Server 的 identity
+func isAutoInc(extra string) bool {
+	e := strings.ToLower(extra)
+	return strings.Contains(e, "auto_increment") || strings.Contains(e, "identity")
+}
+
+// introspectIndexesMySQL 采集 MySQL 索引
+//
+// 主键写入列元数据，其余二级索引写入索引集合
+func introspectIndexesMySQL(ctx context.Context, db gdb.DB, table string, meta *TableMeta) error {
+	rows, err := db.Ctx(ctx).Raw("SHOW INDEX FROM `" + table + "`").All()
+	if err != nil {
+		return err
+	}
+	type idxHolder struct {
+		unique bool
+		cols   []string
+	}
+	holders := map[string]*idxHolder{}
+	order := make([]string, 0)
+	for _, r := range rows {
+		name := r["Key_name"].String()
+		h, ok := holders[name]
+		if !ok {
+			h = &idxHolder{unique: r["Non_unique"].Int() == 0}
+			holders[name] = h
+			order = append(order, name)
+		}
+		h.cols = append(h.cols, r["Column_name"].String())
+	}
+	for _, name := range order {
+		h := holders[name]
+		if name == "PRIMARY" {
+			for i := range meta.Columns {
+				for _, c := range h.cols {
+					if meta.Columns[i].Name == c {
+						meta.Columns[i].IsPK = true
+					}
+				}
+			}
+			continue
+		}
+		meta.Indexes = append(meta.Indexes, IndexMeta{Unique: h.unique, Name: name, Columns: h.cols})
+	}
+	return nil
+}
+
+// tableCommentMySQL 查询 MySQL 表注释
+func tableCommentMySQL(ctx context.Context, db gdb.DB, table string) string {
+	row, err := db.Ctx(ctx).Raw(
+		"SELECT TABLE_COMMENT FROM information_schema.TABLES WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = ?", table,
+	).One()
+	if err != nil || len(row) == 0 {
+		return ""
+	}
+	return row["TABLE_COMMENT"].String()
+}
+
+// introspectIndexesPgsql 采集 PostgreSQL 索引
+//
+// 主键写入列元数据，其余二级索引写入索引集合
+func introspectIndexesPgsql(ctx context.Context, db gdb.DB, table string, meta *TableMeta) error {
+	rows, err := db.Ctx(ctx).Raw(
+		"SELECT indexname, indexdef FROM pg_indexes WHERE schemaname = current_schema() AND tablename = ?", table,
+	).All()
+	if err != nil {
+		return err
+	}
+	for _, r := range rows {
+		name := r["indexname"].String()
+		def := r["indexdef"].String()
+		cols := parsePgIndexCols(def)
+		if len(cols) == 0 {
+			continue
+		}
+		if name == table+"_pkey" {
+			for i := range meta.Columns {
+				for _, c := range cols {
+					if meta.Columns[i].Name == c {
+						meta.Columns[i].IsPK = true
+					}
+				}
+			}
+			continue
+		}
+		meta.Indexes = append(meta.Indexes, IndexMeta{
+			Unique:  strings.Contains(strings.ToUpper(def), "UNIQUE"),
+			Name:    name,
+			Columns: cols,
+		})
+	}
+	return nil
+}
+
+// parsePgIndexCols 从建索引语句中提取列清单
+//
+// 取括号内内容按逗号切分，跳过表达式部分
+func parsePgIndexCols(def string) []string {
+	start := strings.Index(def, "(")
+	end := strings.LastIndex(def, ")")
+	if start < 0 || end <= start {
+		return nil
+	}
+	parts := strings.Split(def[start+1:end], ",")
+	cols := make([]string, 0, len(parts))
+	for _, p := range parts {
+		p = strings.TrimSpace(p)
+		// 表达式索引（如 lower(name)）取首标识符，跳过复杂表达式
+		if i := strings.IndexAny(p, " ("); i > 0 {
+			p = p[:i]
+		}
+		p = strings.Trim(p, `"`)
+		if p != "" {
+			cols = append(cols, p)
+		}
+	}
+	return cols
+}
+
+// tableCommentPgsql 查询 PostgreSQL 表注释
+func tableCommentPgsql(ctx context.Context, db gdb.DB, table string) string {
+	row, err := db.Ctx(ctx).Raw(
+		"SELECT obj_description(c.oid) AS comment FROM pg_class c JOIN pg_namespace n ON n.oid = c.relnamespace WHERE n.nspname = current_schema() AND c.relname = ?", table,
+	).One()
+	if err != nil || len(row) == 0 {
+		return ""
+	}
+	return row["comment"].String()
+}