feat: add source and target database type fields

Add source_db_type and target_db_type to the migration config so the same binary can drive any supported direction.

cmd/go_migrate/main.go

@@ -2,18 +2,17 @@ package main
 
 import (
 	"context"
-	"database/sql"
 	"sync"
 	"time"
 
 	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/config"
-	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/db"
+	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/db-wrapper"
 	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/etl/extractors"
 	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/etl/loaders"
 	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/etl/table_analyzers"
 	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/etl/transformers"
-	"github.com/jackc/pgx/v5/pgxpool"
 	log "github.com/sirupsen/logrus"
+	"golang.org/x/sync/errgroup"
 )
 
 func main() {
@@ -33,11 +32,33 @@ func main() {
 
 	log.Info("=== Starting migration ===")
 
-	sourceDb, targetDb, connError := connectToDatabases()
-	if connError != nil {
-		log.Fatal("Connection error: ", connError)
-	}
+	var wgConnect errgroup.Group
+	var sourceDb, targetDb dbwrapper.DbWrapper
 
+	wgConnect.Go(func() error {
+		var err error
+		sourceDb, err = connectWithTimeout(ctx, migrationConfig.SourceDbType, config.App.SourceDbUrl, 20*time.Second)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	})
+
+	wgConnect.Go(func() error {
+		var err error
+		targetDb, err = connectWithTimeout(ctx, migrationConfig.TargetDbType, config.App.TargetDbUrl, 20*time.Second)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	})
+
+	if err := wgConnect.Wait(); err != nil {
+		log.Error("Connection error: ", err)
+		return
+	}
 	defer sourceDb.Close()
 	defer targetDb.Close()
 
@@ -70,8 +91,8 @@ func main() {
 
 func processMigrationJobs(
 	ctx context.Context,
-	sourceDb *sql.DB,
-	targetDb *pgxpool.Pool,
+	sourceDb dbwrapper.DbWrapper,
+	targetDb dbwrapper.DbWrapper,
 	jobs []config.Job,
 	maxParallelWorkers int,
 ) []JobResult {
@@ -94,7 +115,6 @@ func processMigrationJobs(
 	chJobs := make(chan config.Job, len(jobs))
 	var wgJobs sync.WaitGroup
 
-	targetDbWrapper := db.NewPostgresDbWrapper(targetDb)
 	sourceTableAnalyzer := table_analyzers.NewMssqlTableAnalyzer(sourceDb)
 	targetTableAnalyzer := table_analyzers.NewPostgresTableAnalyzer(targetDb)
 	extractor := extractors.NewMssqlExtractor(sourceDb)
@@ -107,7 +127,7 @@ func processMigrationJobs(
 				log.Infof("[worker %d] >>> Processing job: %s.%s <<<", i, job.SourceTable.Schema, job.SourceTable.Table)
 				res := processMigrationJob(
 					ctx,
-					targetDbWrapper,
+					targetDb,
 					sourceTableAnalyzer,
 					targetTableAnalyzer,
 					extractor,
@@ -138,3 +158,19 @@ func processMigrationJobs(
 
 	return finalResults
 }
+
+func connectWithTimeout(ctx context.Context, dbType string, dbUrl string, timeout time.Duration) (dbwrapper.DbWrapper, error) {
+	localCtx, cancel := context.WithTimeout(ctx, timeout)
+	defer cancel()
+
+	sourceDb, err := dbwrapper.New(dbType)
+	if err != nil {
+		return nil, err
+	}
+
+	if err = sourceDb.Connect(localCtx, dbUrl); err != nil {
+		return nil, err
+	}
+
+	return sourceDb, nil
+}