feat: refactor extractor interface and implement Consume function for ETL process

internal/app/etl/extractors/mssql.go

@@ -5,10 +5,7 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
-	"slices"
 	"strings"
-	"sync"
-	"sync/atomic"
 
 	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/config"
 	"git.ksdemosapps.com/kylesoda/go-migrate/internal/app/convert"
@@ -99,7 +96,7 @@ func errorFromLastRow(
 	}
 }
 
-func (mssqlEx *MssqlExtractor) ProcessPartition(
+func (mssqlEx *MssqlExtractor) Exec(
 	ctx context.Context,
 	tableInfo config.SourceTableInfo,
 	columns []models.ColumnType,
@@ -188,90 +185,3 @@ func (mssqlEx *MssqlExtractor) ProcessPartition(
 
 	return rowsRead, nil
 }
-
-func (mssqlEx *MssqlExtractor) Exec(
-	ctx context.Context,
-	tableInfo config.SourceTableInfo,
-	columns []models.ColumnType,
-	batchSize int,
-	chPartitionsIn <-chan models.Partition,
-	chBatchesOut chan<- models.Batch,
-	chErrorsOut chan<- custom_errors.ExtractorError,
-	chJobErrorsOut chan<- custom_errors.JobError,
-	wgActivePartitions *sync.WaitGroup,
-	rowsRead *int64,
-) {
-	indexPrimaryKey := slices.IndexFunc(columns, func(col models.ColumnType) bool {
-		return strings.EqualFold(col.Name(), tableInfo.PrimaryKey)
-	})
-
-	if indexPrimaryKey == -1 {
-		select {
-		case <-ctx.Done():
-			return
-		case chJobErrorsOut <- custom_errors.JobError{
-			ShouldCancelJob: true,
-			Msg:             "Primary key not found in provided columns",
-		}:
-		}
-
-		return
-	}
-
-	for {
-		if ctx.Err() != nil {
-			return
-		}
-
-		select {
-		case <-ctx.Done():
-			return
-		case partition, ok := <-chPartitionsIn:
-			if !ok {
-				return
-			}
-
-			rowsReadResult, err := mssqlEx.ProcessPartition(
-				ctx,
-				tableInfo,
-				columns,
-				batchSize,
-				partition,
-				indexPrimaryKey,
-				chBatchesOut,
-			)
-
-			if rowsReadResult > 0 {
-				atomic.AddInt64(rowsRead, int64(rowsReadResult))
-			}
-
-			if err != nil {
-				var exError *custom_errors.ExtractorError
-				var jobError *custom_errors.JobError
-				if errors.As(err, &exError) {
-					select {
-					case <-ctx.Done():
-						return
-					case chErrorsOut <- *exError:
-					}
-				} else if errors.As(err, &jobError) {
-					select {
-					case <-ctx.Done():
-						return
-					case chJobErrorsOut <- *jobError:
-					}
-				} else {
-					select {
-					case <-ctx.Done():
-						return
-					case chErrorsOut <- custom_errors.ExtractorError{Partition: partition, Msg: err.Error()}:
-					}
-				}
-
-				continue
-			}
-
-			wgActivePartitions.Done()
-		}
-	}
-}