feat: Enhance serve command to support Matrix files

This change enhances the 'serve' command to support serving files directly from a Terminal Isolation Matrix. It introduces a new 'pkg/tarfs' package that provides an http.FileSystem implementation for tar archives, allowing for a "passthrough" server that serves files directly from the Matrix bundle.

cmd/serve.go

@@ -4,8 +4,10 @@ import (
 	"fmt"
 	"net/http"
 	"os"
+	"strings"
 
 	"github.com/Snider/Borg/pkg/datanode"
+	"github.com/Snider/Borg/pkg/tarfs"
 
 	"github.com/spf13/cobra"
 )
@@ -17,22 +19,32 @@ var serveCmd = &cobra.Command{
 	Long:  `Serves the contents of a packaged PWA file using a static file server.`,
 	Args:  cobra.ExactArgs(1),
 	Run: func(cmd *cobra.Command, args []string) {
-		pwaFile := args[0]
+		dataFile := args[0]
 		port, _ := cmd.Flags().GetString("port")
 
-		pwaData, err := os.ReadFile(pwaFile)
+		data, err := os.ReadFile(dataFile)
 		if err != nil {
-			fmt.Printf("Error reading PWA file: %v\n", err)
+			fmt.Printf("Error reading data file: %v\n", err)
 			return
 		}
 
-		dn, err := datanode.FromTar(pwaData)
-		if err != nil {
-			fmt.Printf("Error creating DataNode from tarball: %v\n", err)
-			return
+		var fs http.FileSystem
+		if strings.HasSuffix(dataFile, ".matrix") {
+			fs, err = tarfs.New(data)
+			if err != nil {
+				fmt.Printf("Error creating TarFS from matrix tarball: %v\n", err)
+				return
+			}
+		} else {
+			dn, err := datanode.FromTar(data)
+			if err != nil {
+				fmt.Printf("Error creating DataNode from tarball: %v\n", err)
+				return
+			}
+			fs = http.FS(dn)
 		}
 
-		http.Handle("/", http.FileServer(http.FS(dn)))
+		http.Handle("/", http.FileServer(fs))
 
 		fmt.Printf("Serving PWA on http://localhost:%s\n", port)
 		err = http.ListenAndServe(":"+port, nil)

docs/README.md

@@ -66,7 +66,7 @@ borg collect pwa [flags]
 
 ### `serve`
 
-Serves the contents of a packaged DataNode file using a static file server.
+Serves the contents of a packaged DataNode or Terminal Isolation Matrix file using a static file server.
 
 **Usage:**
 ```
@@ -78,7 +78,11 @@ borg serve [file] [flags]
 
 **Example:**
 ```
+# Serve a DataNode
 ./borg serve squoosh.dat --port 8888
+
+# Serve a Terminal Isolation Matrix
+./borg serve borg.matrix --port 9999
 ```
 
 ## Terminal Isolation Matrix

examples/serve_matrix.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+# Example of using the 'borg serve' command with a .matrix file.
+
+# This script serves the contents of a .matrix file using a static file server.
+# The main executable 'borg' is built from the project's root.
+# Make sure you have built the project by running 'go build -o borg main.go' in the root directory.
+
+# First, create a .matrix file
+./borg collect github repo https://github.com/Snider/Borg --output borg.matrix --format matrix
+
+# Then, serve it
+./borg serve borg.matrix --port 9999

pkg/tarfs/tarfs.go

@@ -0,0 +1,110 @@
+package tarfs
+
+import (
+	"archive/tar"
+	"bytes"
+	"io"
+	"net/http"
+	"os"
+	"path"
+	"strings"
+	"time"
+)
+
+// TarFS is a http.FileSystem that serves files from a tar archive.
+type TarFS struct {
+	files map[string]*tar.Header
+	data  []byte
+}
+
+// New creates a new TarFS from a tar archive.
+func New(data []byte) (*TarFS, error) {
+	fs := &TarFS{
+		files: make(map[string]*tar.Header),
+		data:  data,
+	}
+
+	tr := tar.NewReader(bytes.NewReader(data))
+	for {
+		hdr, err := tr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, err
+		}
+
+		if strings.HasPrefix(hdr.Name, "rootfs/") {
+			fs.files[strings.TrimPrefix(hdr.Name, "rootfs/")] = hdr
+		}
+	}
+
+	return fs, nil
+}
+
+// Open opens a file from the tar archive.
+func (fs *TarFS) Open(name string) (http.File, error) {
+	name = strings.TrimPrefix(name, "/")
+	if hdr, ok := fs.files[name]; ok {
+		// This is a bit inefficient, but it's the simplest way to
+		// get the file content without pre-indexing everything.
+		tr := tar.NewReader(bytes.NewReader(fs.data))
+		for {
+			h, err := tr.Next()
+			if err == io.EOF {
+				break
+			}
+			if err != nil {
+				return nil, err
+			}
+			if h.Name == hdr.Name {
+				return &tarFile{
+					header:  hdr,
+					content: tr,
+					modTime: hdr.ModTime,
+				}, nil
+			}
+		}
+	}
+
+	return nil, os.ErrNotExist
+}
+
+// tarFile is a http.File that represents a file in a tar archive.
+type tarFile struct {
+	header  *tar.Header
+	content io.Reader
+	modTime time.Time
+}
+
+func (f *tarFile) Close() error               { return nil }
+func (f *tarFile) Read(p []byte) (int, error) { return f.content.Read(p) }
+func (f *tarFile) Seek(offset int64, whence int) (int64, error) {
+	return 0, io.ErrUnexpectedEOF
+}
+
+func (f *tarFile) Readdir(count int) ([]os.FileInfo, error) {
+	return nil, os.ErrInvalid
+}
+
+func (f *tarFile) Stat() (os.FileInfo, error) {
+	return &tarFileInfo{
+		name:    path.Base(f.header.Name),
+		size:    f.header.Size,
+		modTime: f.modTime,
+	}, nil
+}
+
+// tarFileInfo is a os.FileInfo that represents a file in a tar archive.
+type tarFileInfo struct {
+	name    string
+	size    int64
+	modTime time.Time
+}
+
+func (i *tarFileInfo) Name() string       { return i.name }
+func (i *tarFileInfo) Size() int64        { return i.size }
+func (i *tarFileInfo) Mode() os.FileMode  { return 0444 }
+func (i *tarFileInfo) ModTime() time.Time { return i.modTime }
+func (i *tarFileInfo) IsDir() bool        { return false }
+func (i *tarFileInfo) Sys() interface{}   { return nil }