path filter (wip)

digest/calculator.go

@@ -8,15 +8,17 @@ import (
 	"io"
 	"log"
 	"os"
-	"path"
 	"path/filepath"
 	"sync"
 	"time"
 
 	"github.com/soerenkoehler/go-chdiff/util"
 )
 
-type Calculator func(rootPath string, algorithm HashType) Digest
+type Calculator func(
+	rootPath string,
+	exclude util.PathFilter,
+	algorithm HashType) Digest
 
 type digestEntry struct {
 	file string
@@ -25,23 +27,35 @@ type digestEntry struct {
 
 type digestContext struct {
 	rootPath  string
+	exclude   util.PathFilter
 	algorithm HashType
 	waitGroup *sync.WaitGroup
 	digest    chan digestEntry
 }
 
-func Calculate(rootPath string, algorithm HashType) Digest {
+func Calculate(
+	rootPath string,
+	exclude util.PathFilter,
+	algorithm HashType) Digest {
+
 	context := digestContext{
 		rootPath:  rootPath,
+		exclude:   exclude,
 		algorithm: algorithm,
 		waitGroup: &sync.WaitGroup{},
 		digest:    make(chan digestEntry),
 	}
 
 	go func() {
-		context.processPath(context.rootPath)
+		defer close(context.digest)
+
+		absPath, err := filepath.Abs(context.rootPath)
+		if err == nil {
+			return
+		}
+
+		context.processPath(absPath)
 		context.waitGroup.Wait()
-		close(context.digest)
 	}()
 
 	result := NewDigest(rootPath, time.Now())
@@ -55,6 +69,12 @@ func Calculate(rootPath string, algorithm HashType) Digest {
 func (context digestContext) processPath(path string) {
 	context.waitGroup.Add(1)
 	go func() {
+		defer context.waitGroup.Done()
+
+		if context.exclude.Matches(path) {
+			return
+		}
+
 		switch info := util.Stat(path); {
 		case info.IsSymlink:
 			log.Printf("[W] skipping symlink: %s => %s", path, info.Target)
@@ -63,7 +83,7 @@ func (context digestContext) processPath(path string) {
 		default:
 			context.processFile(path)
 		}
-		context.waitGroup.Done()
+
 	}()
 }
 
@@ -75,7 +95,7 @@ func (context digestContext) processDir(dir string) {
 	}
 
 	for _, entry := range entries {
-		context.processPath(path.Join(dir, entry.Name()))
+		context.processPath(filepath.Join(dir, entry.Name()))
 	}
 }
 

digest/calculator_test.go

@@ -4,10 +4,11 @@ import (
 	"io"
 	"math/rand"
 	"os"
-	"path"
+	"path/filepath"
 	"testing"
 
 	"github.com/soerenkoehler/go-chdiff/digest"
+	"github.com/soerenkoehler/go-chdiff/util"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
@@ -73,7 +74,7 @@ func (s *TestSuiteCalculator) verifyDigest(
 	testdata []testCase,
 	algorithm digest.HashType) {
 
-	digest := digest.Calculate(createData(s, testdata), algorithm)
+	digest := digest.Calculate(createData(s, testdata), util.PathFilter{}, algorithm)
 
 	require.Equal(s.T(), len(testdata), len(*digest.Entries))
 
@@ -89,15 +90,15 @@ func createData(
 	root := s.T().TempDir()
 
 	for _, dataPoint := range testdata {
-		file := path.Join(root, dataPoint.path)
+		file := filepath.Join(root, dataPoint.path)
 		createRandomFile(file, dataPoint.size, dataPoint.seed)
 	}
 
 	return root
 }
 
 func createRandomFile(file string, size, seed int64) {
-	err := os.MkdirAll(path.Dir(file), 0700)
+	err := os.MkdirAll(filepath.Dir(file), 0700)
 	if err != nil {
 		panic(err)
 	}

main.go

@@ -8,6 +8,7 @@ import (
 	"github.com/soerenkoehler/go-chdiff/chdiff"
 	"github.com/soerenkoehler/go-chdiff/diff"
 	"github.com/soerenkoehler/go-chdiff/digest"
+	"github.com/soerenkoehler/go-chdiff/util"
 )
 
 var _Version = "DEV"
@@ -23,7 +24,7 @@ func (*DefaultDependencies) DigestWrite(d digest.Digest, df string) error {
 }
 
 func (*DefaultDependencies) DigestCalculate(rp string, ht digest.HashType) digest.Digest {
-	return digest.Calculate(rp, ht)
+	return digest.Calculate(rp, util.PathFilter{}, ht)
 }
 
 func (*DefaultDependencies) DigestCompare(old, new digest.Digest) diff.Diff {

util/file.go

@@ -4,8 +4,15 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"strings"
 )
 
+// PathFilter defines patterns to match against paths
+type PathFilter struct {
+	Prefix []string
+	Suffix []string
+}
+
 // PathInfo distilles information from FileInfo and Readlink
 type PathInfo struct {
 	IsDir     bool
@@ -31,3 +38,17 @@ func Stat(path string) PathInfo {
 		IsSymlink: false,
 		Target:    path}
 }
+
+func (filter *PathFilter) Matches(path string) bool {
+	for _, pattern := range filter.Prefix {
+		if strings.HasPrefix(path, pattern) {
+			return true
+		}
+	}
+	for _, pattern := range filter.Suffix {
+		if strings.HasSuffix(path, pattern) {
+			return true
+		}
+	}
+	return false
+}