feat: add MySQL reader and writer

2026-10-03 12:36:39 +02:00
parent b38f53c603
commit 7a9219b6e3
53 changed files with 12311 additions and 0 deletions
@@ -0,0 +1,152 @@
+package mysql
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"io"
+	"os"
+	"sort"
+	"strings"
+
+	"git.warky.dev/wdevs/relspecgo/pkg/mariadb"
+	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/writers"
+)
+
+type Writer struct {
+	options *writers.WriterOptions
+	writer  io.Writer
+}
+
+func NewWriter(options *writers.WriterOptions) *Writer { return &Writer{options: options} }
+func (w *Writer) WriteDatabase(db *models.Database) error {
+	if w.options == nil {
+		return fmt.Errorf("writer options are required")
+	}
+	if conn, ok := w.options.Metadata["connection_string"].(string); ok && conn != "" {
+		return w.execute(db, conn)
+	}
+	if w.writer == nil {
+		if w.options.OutputPath != "" {
+			f, err := os.Create(w.options.OutputPath)
+			if err != nil {
+				return err
+			}
+			defer f.Close()
+			w.writer = f
+		} else {
+			w.writer = os.Stdout
+		}
+	}
+	fmt.Fprintf(w.writer, "-- MySQL Database Schema\n-- Database: %s\n-- Generated by RelSpec\n\n", db.Name)
+	for _, s := range db.Schemas {
+		if err := w.WriteSchema(s); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+func (w *Writer) WriteSchema(s *models.Schema) error {
+	for _, t := range s.Tables {
+		if err := w.writeTable(s, t); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+func (w *Writer) WriteTable(t *models.Table) error {
+	if w.writer == nil {
+		w.writer = os.Stdout
+	}
+	return w.writeTable(nil, t)
+}
+func (w *Writer) writeTable(s *models.Schema, t *models.Table) error {
+	name := t.Name
+	if s != nil {
+		name = fmt.Sprintf("%s.%s", quote(s.Name), quote(t.Name))
+	} else {
+		name = quote(name)
+	}
+	cols := make([]*models.Column, 0, len(t.Columns))
+	for _, c := range t.Columns {
+		cols = append(cols, c)
+	}
+	sort.Slice(cols, func(i, j int) bool { return cols[i].Sequence < cols[j].Sequence })
+	defs := []string{}
+	pk := []string{}
+	for _, c := range cols {
+		d := fmt.Sprintf("  %s %s", quote(c.Name), mariadb.ConvertCanonicalToMariaDB(c.Type))
+		if c.Length > 0 && strings.EqualFold(c.Type, "string") {
+			d = fmt.Sprintf("  %s VARCHAR(%d)", quote(c.Name), c.Length)
+		}
+		if c.NotNull {
+			d += " NOT NULL"
+		}
+		if c.AutoIncrement {
+			d += " AUTO_INCREMENT"
+		}
+		if c.Default != nil {
+			d += fmt.Sprintf(" DEFAULT %s", writers.QuoteDefaultValue(fmt.Sprint(c.Default), c.Type))
+		}
+		defs = append(defs, d)
+		if c.IsPrimaryKey {
+			pk = append(pk, quote(c.Name))
+		}
+	}
+	for _, c := range t.Constraints {
+		if c.Type == models.PrimaryKeyConstraint {
+			pk = nil
+			for _, n := range c.Columns {
+				pk = append(pk, quote(n))
+			}
+			break
+		}
+	}
+	if len(pk) > 0 {
+		defs = append(defs, "  PRIMARY KEY ("+strings.Join(pk, ", ")+")")
+	}
+	for _, c := range t.Constraints {
+		if c.Type == models.UniqueConstraint {
+			defs = append(defs, fmt.Sprintf("  CONSTRAINT %s UNIQUE (%s)", quote(c.Name), quoted(c.Columns)))
+		}
+	}
+	sql := fmt.Sprintf("CREATE TABLE IF NOT EXISTS %s (\n%s\n) ENGINE=InnoDB;\n\n", name, strings.Join(defs, ",\n"))
+	if _, err := io.WriteString(w.writer, sql); err != nil {
+		return err
+	}
+	return nil
+}
+func (w *Writer) execute(dbm *models.Database, conn string) error {
+	var b strings.Builder
+	old := w.writer
+	w.writer = &b
+	if err := w.WriteDatabase(dbm); err != nil {
+		w.writer = old
+		return err
+	}
+	w.writer = old
+	db, err := sql.Open("mysql", conn)
+	if err != nil {
+		return fmt.Errorf("failed to connect: %w", err)
+	}
+	defer db.Close()
+	for _, stmt := range strings.Split(b.String(), ";\n") {
+		stmt = strings.TrimSpace(stmt)
+		if stmt == "" || strings.HasPrefix(stmt, "--") {
+			continue
+		}
+		if _, err := db.ExecContext(context.Background(), stmt); err != nil {
+			return fmt.Errorf("failed to execute SQL: %w", err)
+		}
+	}
+	return nil
+}
+func quote(s string) string { return "`" + strings.ReplaceAll(s, "`", "``") + "`" }
+func quoted(xs []string) string {
+	out := make([]string, len(xs))
+	for i, x := range xs {
+		out[i] = quote(x)
+	}
+	return strings.Join(out, ", ")
+}
@@ -0,0 +1,37 @@
+package mysql
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/writers"
+)
+
+func TestWriterGeneratesMySQLDDL(t *testing.T) {
+	db := models.InitDatabase("app")
+	s := models.InitSchema("app")
+	table := models.InitTable("users", "app")
+	table.Columns["id"] = models.InitColumn("id", "users", "app")
+	table.Columns["id"].Type = "int"
+	table.Columns["id"].IsPrimaryKey = true
+	table.Columns["id"].NotNull = true
+	table.Columns["name"] = models.InitColumn("name", "users", "app")
+	table.Columns["name"].Type = "string"
+	table.Columns["name"].Length = 80
+	s.Tables = append(s.Tables, table)
+	db.Schemas = append(db.Schemas, s)
+	var out bytes.Buffer
+	w := NewWriter(&writers.WriterOptions{Metadata: map[string]interface{}{}})
+	w.writer = &out
+	if err := w.WriteDatabase(db); err != nil {
+		t.Fatal(err)
+	}
+	got := out.String()
+	for _, want := range []string{"CREATE TABLE IF NOT EXISTS `app`.`users`", "`id` INT NOT NULL", "`name` VARCHAR(80)", "PRIMARY KEY (`id`)"} {
+		if !strings.Contains(got, want) {
+			t.Errorf("DDL missing %q:\n%s", want, got)
+		}
+	}
+}