Merge branch 'main' of github.com:SongStitch/anchor into feature/add-…

…ci-cleanup

cmd/anchor/root.go

@@ -2,10 +2,13 @@ package anchor
 
 import (
 	"bufio"
+	"context"
 	"fmt"
 	"os"
+	"os/signal"
 	"path/filepath"
 	"strings"
+	"syscall"
 
 	"github.com/fatih/color"
 	"github.com/moby/buildkit/frontend/dockerfile/parser"
@@ -41,6 +44,14 @@ var rootCmd = &cobra.Command{
 	SilenceUsage:  true,
 	SilenceErrors: true,
 	RunE: func(cmd *cobra.Command, args []string) error {
+		ctx, cancel := context.WithCancel(context.Background())
+		c := make(chan os.Signal, 1)
+		signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+		go func() {
+			<-c
+			cancel()
+			os.Exit(1)
+		}()
 
 		if anchor.IsDockerInstalled() {
 			if !anchor.IsDockerRunning() {
@@ -78,30 +89,42 @@ var rootCmd = &cobra.Command{
 		}
 		appendArch := len(options.Architectures) > 1
 
+		content, err := os.Open(options.InputFile)
+		if err != nil {
+			return err
+		}
+		defer content.Close()
+		lines := []string{}
+		scanner := bufio.NewScanner(content)
+		for scanner.Scan() {
+			lines = append(lines, scanner.Text())
+		}
+
+		if err := scanner.Err(); err != nil {
+			return err
+		}
 		for _, architecture := range options.Architectures {
 			content, err := os.Open(options.InputFile)
 			if err != nil {
 				return err
 			}
-
 			defer content.Close()
 			result, err := parser.Parse(content)
 			if err != nil {
 				return err
 			}
 
 			node := result.AST
-			anchor.PrintNode(node)
 
 			color.Cyan("Anchoring to architecture: %s\n", architecture)
 			image := ""
-			err = anchor.ParseNode(node, architecture, &image)
+			err = anchor.ParseNode(ctx, node, architecture, &image)
 			if err != nil {
 				return err
 			}
 
 			var builder strings.Builder
-			anchor.WriteDockerfile(&builder, node, true)
+			anchor.WriteDockerfile(&builder, node, true, 0, lines)
 			outputName := options.OutputFile
 			if appendArch {
 				outputName = fmt.Sprintf("%s.%s", outputName, architecture)

docker.go

@@ -1,6 +1,7 @@
 package anchor
 
 import (
+	"context"
 	"fmt"
 	"os/exec"
 	"strings"
@@ -28,7 +29,19 @@ func attachDockerSha(node *parser.Node) (string, error) {
 	return node.Value, nil
 }
 
-func WriteDockerfile(builder *strings.Builder, node *parser.Node, useOriginal bool) {
+func WriteDockerfile(builder *strings.Builder, node *parser.Node, useOriginal bool, currentLine int, lines []string) int {
+	// this allows us to maintain things like comments and newlines in the original Dockerfile
+	if currentLine != 0 && node.StartLine != 0 && currentLine < node.StartLine {
+		for i := currentLine + 1; i < node.StartLine; i++ {
+			builder.WriteString(lines[i-1])
+			builder.WriteString("\n")
+		}
+	}
+	if currentLine == 0 {
+		currentLine = 1
+	} else if node.EndLine != 0 {
+		currentLine = node.EndLine
+	}
 	if node.Value == "FROM" || node.Value == "RUN" {
 		useOriginal = false
 	}
@@ -46,27 +59,18 @@ func WriteDockerfile(builder *strings.Builder, node *parser.Node, useOriginal bo
 		builder.WriteString(s)
 	}
 	for _, child := range node.Children {
-		WriteDockerfile(builder, child, useOriginal)
-		builder.WriteString("\n\n")
+		currentLine = WriteDockerfile(builder, child, useOriginal, currentLine, lines)
+		builder.WriteString("\n")
 	}
 
 	if node.Next != nil {
 		builder.WriteString(" ")
-		WriteDockerfile(builder, node.Next, useOriginal)
-	}
-}
-
-func PrintNode(node *parser.Node) {
-	for _, child := range node.Children {
-		PrintNode(child)
-	}
-
-	if node.Next != nil {
-		PrintNode(node.Next)
+		currentLine = WriteDockerfile(builder, node.Next, useOriginal, currentLine, lines)
 	}
+	return currentLine
 }
 
-func ParseNode(node *parser.Node, architecture string, image *string) error {
+func ParseNode(ctx context.Context, node *parser.Node, architecture string, image *string) error {
 	if node == nil {
 		return nil
 	}
@@ -79,16 +83,16 @@ func ParseNode(node *parser.Node, architecture string, image *string) error {
 		}
 		*image = newImage
 	} else if node.Value == "RUN" {
-		err := parseRunCommand(node.Next, architecture, *image)
+		err := parseRunCommand(ctx, node.Next, architecture, *image)
 		if err != nil {
 			return err
 		}
 	} else if node.Next != nil {
-		ParseNode(node.Next, architecture, image)
+		ParseNode(ctx, node.Next, architecture, image)
 	}
 
 	for _, child := range node.Children {
-		ParseNode(child, architecture, image)
+		ParseNode(ctx, child, architecture, image)
 	}
 	return nil
 }

packages.go

@@ -2,6 +2,7 @@ package anchor
 
 import (
 	"bytes"
+	"context"
 	"fmt"
 	"os/exec"
 	"strings"
@@ -10,16 +11,14 @@ import (
 )
 
 func fetchPackageVersions(
-	packages []string,
-	architecture string,
-	image string,
+	ctx context.Context, packages []string, architecture string, image string,
 ) (map[string]string, error) {
 	var stdoutBuf, stderrBuf bytes.Buffer
 	command := "dpkg --add-architecture " + architecture + " && apt-get update && apt-cache show --"
 	for _, pkg := range packages {
 		command += " " + pkg + ":" + architecture
 	}
-	c := exec.Command("docker", "run", "--rm", image, "bash", "-c", command) // #nosec G204
+	c := exec.CommandContext(ctx, "docker", "run", "--rm", image, "bash", "-c", command) // #nosec G204
 	c.Stdout = &stdoutBuf
 	c.Stderr = &stderrBuf // Use a buffer to capture stderr output
 
@@ -97,7 +96,7 @@ func parseCommand(command string) []string {
 	return packages
 }
 
-func parseRunCommand(node *parser.Node, architecture string, image string) error {
+func parseRunCommand(ctx context.Context, node *parser.Node, architecture string, image string) error {
 	if node == nil {
 		return nil
 	}
@@ -108,7 +107,7 @@ func parseRunCommand(node *parser.Node, architecture string, image string) error
 		if len(packageNames) == 0 {
 			continue
 		}
-		packageMap, err := fetchPackageVersions(packageNames, architecture, image)
+		packageMap, err := fetchPackageVersions(ctx, packageNames, architecture, image)
 		if err != nil {
 			return err
 		}