feat: add configuration parsing and job definitions

Add a YAML config schema for migration jobs (source/target schema, table, primary key, options) and parse it at startup.

cmd/go_migrate/main.go

@@ -1,25 +1,49 @@
 package main
 
 import (
+	"context"
+	"time"
+
 	log "github.com/sirupsen/logrus"
 )
 
 type MigrationJob struct {
-	Schema string
-	Table  string
+	Schema     string
+	Table      string
+	PrimaryKey string
 }
 
 var migrationJobs []MigrationJob = []MigrationJob{
 	{
-		Schema: "demo",
-		Table:  "users",
+		Schema:     "demo",
+		Table:      "users",
+		PrimaryKey: "id",
+	},
+	{
+		Schema:     "analytics",
+		Table:      "events",
+		PrimaryKey: "ID_events",
 	},
 }
 
+const (
+	NumExtractors  int   = 4
+	NumLoaders     int   = 8
+	ChunkSize      int   = 25000
+	QueueSize      int   = 8
+	ChunksPerBatch int   = 16
+	RowsPerBatch   int64 = int64(ChunkSize * ChunksPerBatch)
+)
+
 func main() {
 	configureLog()
-	log.Info("Starting migration...")
-	// log.Debugf("Migration jobs: %+v", migrationJobs)
+	startTime := time.Now()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	log.Info("=== Starting migration ===")
+	log.Infof("Number of loaders: %d, Chunk size: %d", NumLoaders, ChunkSize)
 
 	sourceDb, targetDb, connError := connectToDatabases()
 	if connError != nil {
@@ -30,9 +54,11 @@ func main() {
 	defer targetDb.Close()
 
 	for _, job := range migrationJobs {
-		log.Infof("Processing job: %+v", job)
-		processMigrationJob(sourceDb, targetDb, job)
+		log.Infof(">>> Processing job: %s.%s <<<", job.Schema, job.Table)
+		processMigrationJob(ctx, sourceDb, targetDb, job)
 	}
 
-	log.Info("Migration completed successfully!")
+	totalDuration := time.Since(startTime)
+	log.Infof("=== Migration completed successfully! ===")
+	log.Infof("Total migration time: %v", totalDuration)
 }