From 903e999cdcb55894fdfeb874dcc63f4f1012020b Mon Sep 17 00:00:00 2001
From: Andrey Smirnov <Smirnov.Andrey@gmail.com>
Date: Fri, 13 Mar 2015 21:23:22 +0300
Subject: [PATCH] Refactor checksum parsing out of package parsing code. #71

---
 deb/package.go       | 62 +++++++-----------------------------------
 deb/package_files.go | 65 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+), 52 deletions(-)

diff --git a/deb/package.go b/deb/package.go
index 8dddda0c..ba0d6956 100644
--- a/deb/package.go
+++ b/deb/package.go
@@ -114,62 +114,20 @@ func NewSourcePackageFromControlFile(input Stanza) (*Package, error) {
 	delete(input, "Version")
 	delete(input, "Architecture")
 
+	var err error
+
 	files := make(PackageFiles, 0, 3)
-
-	parseSums := func(field string, setter func(sum *utils.ChecksumInfo, data string)) error {
-		for _, line := range strings.Split(input[field], "\n") {
-			line = strings.TrimSpace(line)
-			if line == "" {
-				continue
-			}
-			parts := strings.Fields(line)
-
-			if len(parts) < 3 {
-				return fmt.Errorf("unparseable hash sum line: %#v", line)
-			}
-
-			size, err := strconv.ParseInt(parts[1], 10, 64)
-			if err != nil {
-				return fmt.Errorf("unable to parse size: %s", err)
-			}
-
-			filename := filepath.Base(parts[len(parts)-1])
-
-			found := false
-			pos := 0
-			for i, file := range files {
-				if file.Filename == filename {
-					found = true
-					pos = i
-					break
-				}
-			}
-
-			if !found {
-				files = append(files, PackageFile{Filename: filename, downloadPath: input["Directory"]})
-				pos = len(files) - 1
-			}
-
-			files[pos].Checksums.Size = size
-			setter(&files[pos].Checksums, parts[0])
-		}
-
-		delete(input, field)
-
-		return nil
-	}
-
-	err := parseSums("Files", func(sum *utils.ChecksumInfo, data string) { sum.MD5 = data })
+	files, err = files.ParseSumFields(input)
 	if err != nil {
 		return nil, err
 	}
-	err = parseSums("Checksums-Sha1", func(sum *utils.ChecksumInfo, data string) { sum.SHA1 = data })
-	if err != nil {
-		return nil, err
-	}
-	err = parseSums("Checksums-Sha256", func(sum *utils.ChecksumInfo, data string) { sum.SHA256 = data })
-	if err != nil {
-		return nil, err
+
+	delete(input, "Files")
+	delete(input, "Checksums-Sha1")
+	delete(input, "Checksums-Sha256")
+
+	for i := range files {
+		files[i].downloadPath = input["Directory"]
 	}
 
 	result.UpdateFiles(files)
diff --git a/deb/package_files.go b/deb/package_files.go
index 31a37cbe..489b67b1 100644
--- a/deb/package_files.go
+++ b/deb/package_files.go
@@ -2,12 +2,15 @@ package deb
 
 import (
 	"encoding/binary"
+	"fmt"
 	"github.com/smira/aptly/aptly"
 	"github.com/smira/aptly/utils"
 	"hash/fnv"
 	"os"
 	"path/filepath"
 	"sort"
+	"strconv"
+	"strings"
 )
 
 // PackageFile is a single file entry in package
@@ -76,3 +79,65 @@ func (files PackageFiles) Swap(i, j int) {
 func (files PackageFiles) Less(i, j int) bool {
 	return files[i].Filename < files[j].Filename
 }
+
+func (files PackageFiles) parseSumField(input string, setter func(sum *utils.ChecksumInfo, data string)) (PackageFiles, error) {
+	for _, line := range strings.Split(input, "\n") {
+		line = strings.TrimSpace(line)
+		if line == "" {
+			continue
+		}
+		parts := strings.Fields(line)
+
+		if len(parts) < 3 {
+			return nil, fmt.Errorf("unparseable hash sum line: %#v", line)
+		}
+
+		size, err := strconv.ParseInt(parts[1], 10, 64)
+		if err != nil {
+			return nil, fmt.Errorf("unable to parse size: %s", err)
+		}
+
+		filename := filepath.Base(parts[len(parts)-1])
+
+		found := false
+		pos := 0
+		for i, file := range files {
+			if file.Filename == filename {
+				found = true
+				pos = i
+				break
+			}
+		}
+
+		if !found {
+			files = append(files, PackageFile{Filename: filename})
+			pos = len(files) - 1
+		}
+
+		files[pos].Checksums.Size = size
+		setter(&files[pos].Checksums, parts[0])
+	}
+
+	return files, nil
+}
+
+// ParseSumFields populates PackageFiles by parsing stanza checksums fields
+func (files PackageFiles) ParseSumFields(stanza Stanza) (PackageFiles, error) {
+	var err error
+
+	files, err = files.parseSumField(stanza["Files"], func(sum *utils.ChecksumInfo, data string) { sum.MD5 = data })
+	if err != nil {
+		return nil, err
+	}
+
+	files, err = files.parseSumField(stanza["Checksums-Sha1"], func(sum *utils.ChecksumInfo, data string) { sum.SHA1 = data })
+	if err != nil {
+		return nil, err
+	}
+	files, err = files.parseSumField(stanza["Checksums-Sha256"], func(sum *utils.ChecksumInfo, data string) { sum.SHA256 = data })
+	if err != nil {
+		return nil, err
+	}
+
+	return files, nil
+}