adding regexp capabilities to speed up pattern checks per line dras…

…tically

internal/analyser/loader.go

@@ -12,8 +12,8 @@ type Loader interface {
 }
 
 type LoadedFile struct {
- File  *os.File
- Threshold config.Options
+ File *os.File
+ Options config.Options
 }
 
 type FileLoader struct {
@@ -29,7 +29,7 @@ func (f *FileLoader) Load() ([]LoadedFile, error) {
  if err != nil {
  return loaded, err
  }
- loaded = append(loaded, LoadedFile{File: opened, Threshold: individualFile.Threshold})
+ loaded = append(loaded, LoadedFile{File: opened, Options: individualFile.Threshold})
  }
  return loaded, nil
 }

internal/analyser/strategy.go → internal/analyser/modes.go

@@ -3,7 +3,8 @@ package analyser
 import (
  "bufio"
  "log/slog"
- "regexp"
+
+ "github.com/symonk/log-analyse/internal/re"
 )
 
 var strategyMap = map[string]func(loadedFile LoadedFile) []string{
@@ -16,15 +17,12 @@ var strategyMap = map[string]func(loadedFile LoadedFile) []string{
 func seqScanStrategyFn(loadedFile LoadedFile) []string {
  lines := make([]string, 0)
  scanner := bufio.NewScanner(loadedFile.File)
+ patterns, _ := re.CompileSlice(loadedFile.Options.Patterns)
  for scanner.Scan() {
  line := scanner.Text()
- for _, pattern := range loadedFile.Threshold.Patterns {
- ok, err := regexp.Match(pattern, []byte(line))
- if err != nil {
- slog.Error("error matching line with pattern", slog.String("line", line), slog.String("pattern", pattern))
- }
- if ok {
- slog.Info("matched", slog.String("line", line), slog.String("pattern", pattern))
+ for _, pattern := range patterns {
+ if ok := pattern.Match([]byte(line)); ok {
+ slog.Info("matched", slog.String("line", line), slog.Any("pattern", pattern))
  lines = append(lines, line)
  }
  }

internal/re/re.go

@@ -0,0 +1,24 @@
+package re
+
+import (
+ "errors"
+ "regexp"
+)
+
+// CompileSlice takes a slice of string of what could be
+// regular expression patterns, attempts to compile them and return
+// the compiled pattern for use along with a slice of errors for any
+// that failed.
+func CompileSlice(patterns []string) ([]*regexp.Regexp, error) {
+ errs := make([]error, 0, len(patterns))
+ regexps := make([]*regexp.Regexp, 0, len(patterns))
+ for _, pattern := range patterns {
+ c, err := regexp.Compile(pattern)
+ if err != nil {
+ errs = append(errs, err)
+ } else {
+ regexps = append(regexps, c)
+ }
+ }
+ return regexps, errors.Join(errs...)
+}

internal/re/re_test.go

@@ -0,0 +1 @@
+package re