add field-list support self-define region fields

maker/golang/main.go

@@ -12,6 +12,8 @@ import (
 	"log/slog"
 	"os"
 	"regexp"
+	"sort"
+	"strconv"
 	"strings"
 	"time"
 )
@@ -74,6 +76,78 @@ func applyLogLevel(logLevel string) error {
 	return nil
 }
 
+var pattern = regexp.MustCompile("^(\\d+(-\\d+)?)$")
+
+func getFilterFields(fieldList string) ([]int, error) {
+	if len(fieldList) == 0 {
+		return []int{}, nil
+	}
+
+	var fields []int
+	var mapping = make(map[string]string)
+	fList := strings.Split(fieldList, ",")
+	for _, f := range fList {
+		f = strings.TrimSpace(f)
+		if len(f) == 0 {
+			return nil, fmt.Errorf("empty field index value `%s`", f)
+		}
+
+		ms := pattern.FindString(f)
+		if len(ms) == 0 {
+			return nil, fmt.Errorf("field `%s` is not a number or number range", f)
+		}
+
+		if strings.Index(ms, "-") == -1 {
+			if _, ok := mapping[ms]; ok {
+				return nil, fmt.Errorf("duplicate option `%s`", f)
+			}
+
+			idx, err := strconv.Atoi(ms)
+			if err != nil {
+				return nil, fmt.Errorf("field index `%s` not an integer", f)
+			}
+
+			mapping[ms] = ms
+			fields = append(fields, idx)
+			continue
+		}
+
+		ra := strings.Split(ms, "-")
+		if len(ra) != 2 {
+			return nil, fmt.Errorf("invalid field index range `%s`", ms)
+		}
+
+		start, err := strconv.Atoi(ra[0])
+		if err != nil {
+			return nil, fmt.Errorf("range start `%s` not an integer", ra[0])
+		}
+
+		end, err := strconv.Atoi(ra[1])
+		if err != nil {
+			return nil, fmt.Errorf("range end `%s` not an integer", ra[1])
+		}
+
+		if start > end {
+			return nil, fmt.Errorf("index range start(%d) should <= end(%d)", start, end)
+		}
+
+		for i := start; i <= end; i++ {
+			s := strconv.Itoa(i)
+			if _, ok := mapping[s]; ok {
+				return nil, fmt.Errorf("duplicate option `%s`", s)
+			}
+
+			mapping[s] = s
+			fields = append(fields, i)
+		}
+	}
+
+	// sort the fields
+	sort.Ints(fields)
+	// fmt.Printf("%+v\n", fields)
+	return fields, nil
+}
+
 func genDb() {
 	var err error
 	var srcFile, dstFile = "", ""
@@ -122,11 +196,15 @@ func genDb() {
 		return
 	}
 
-	slog.Info("field-list", "value", fieldList)
+	fields, err := getFilterFields(fieldList)
+	if err != nil {
+		slog.Error("failed to get filter fields", "error", err)
+		return
+	}
 
 	// make the binary file
 	tStart := time.Now()
-	maker, err := xdb.NewMaker(indexPolicy, srcFile, dstFile)
+	maker, err := xdb.NewMaker(indexPolicy, srcFile, dstFile, fields)
 	if err != nil {
 		fmt.Printf("failed to create %s\n", err)
 		return

maker/golang/xdb/maker.go

@@ -54,6 +54,7 @@ import (
 	"fmt"
 	"log/slog"
 	"os"
+	"strings"
 	"time"
 )
 
@@ -69,13 +70,16 @@ type Maker struct {
 	srcHandle *os.File
 	dstHandle *os.File
 
+	// self-define field index
+	fields []int
+
 	indexPolicy IndexPolicy
 	segments    []*Segment
 	regionPool  map[string]uint32
 	vectorIndex []byte
 }
 
-func NewMaker(policy IndexPolicy, srcFile string, dstFile string) (*Maker, error) {
+func NewMaker(policy IndexPolicy, srcFile string, dstFile string, fields []int) (*Maker, error) {
 	// open the source file with READONLY mode
 	srcHandle, err := os.OpenFile(srcFile, os.O_RDONLY, 0600)
 	if err != nil {
@@ -92,6 +96,9 @@ func NewMaker(policy IndexPolicy, srcFile string, dstFile string) (*Maker, error
 		srcHandle: srcHandle,
 		dstHandle: dstHandle,
 
+		// fields filter index
+		fields: fields,
+
 		indexPolicy: policy,
 		segments:    []*Segment{},
 		regionPool:  map[string]uint32{},
@@ -133,6 +140,28 @@ func (m *Maker) initDbHeader() error {
 	return nil
 }
 
+func (m *Maker) getFilteredRegion(region string) (string, error) {
+	if len(m.fields) == 0 {
+		return region, nil
+	}
+
+	fs := strings.Split(region, "|")
+	var sb []string
+	for _, idx := range m.fields {
+		if idx < 0 {
+			return "", fmt.Errorf("negative filter index %d", idx)
+		}
+
+		if idx >= len(fs) {
+			return "", fmt.Errorf("field index %d exceeded the max length of %d", idx, len(fs))
+		}
+
+		sb = append(sb, fs[idx])
+	}
+
+	return strings.Join(sb, "|"), nil
+}
+
 func (m *Maker) loadSegments() error {
 	slog.Info("try to load the segments ... ")
 	var last *Segment = nil
@@ -146,6 +175,14 @@ func (m *Maker) loadSegments() error {
 			return err
 		}
 
+		// apply the field filter
+		region, err := m.getFilteredRegion(seg.Region)
+		if err != nil {
+			return err
+		}
+
+		// slog.Info("filtered", "region", region)
+		seg.Region = region
 		m.segments = append(m.segments, seg)
 		last = seg
 		return nil
@@ -241,7 +278,7 @@ func (m *Maker) Start() error {
 		}
 
 		// @Note: data length should be the length of bytes.
-		// this works find cuz of the string feature (byte sequence) of golang.
+		// this works fine because of the string feature (byte sequence) of golang.
 		var dataLen = len(seg.Region)
 		if dataLen < 1 {
 			// @TODO: could this even be a case ?

maker/golang/xdb/util.go

@@ -94,7 +94,7 @@ func IterateSegments(handle *os.File, before func(l string), cb func(seg *Segmen
 			Region:  ps[2],
 		}
 
-		// check and automatic merging the Consecutive Segments which means:
+		// check and automatic merging the Consecutive Segments, which means:
 		// 1, region info is the same
 		// 2, last.eip+1 = cur.sip
 		if last == nil {