added goals; refactored to filetree

README.md

@@ -2,4 +2,13 @@
 ```
 docker build -t die-test:latest .
 go run main.go
-```
+```
+
+# TODO:
+
+[x] Extract docker layers from api
+[x] Represent layers as generic tree
+[x] Stack ordere tree list together as fake unionfs tree
+[ ] Diff trees
+[ ] Add ui for browsing layers
+[ ] Add ui for diffing stack to layer

filetree.go

@@ -1,136 +0,0 @@
-package main
-
-import (
-	"errors"
-	"strings"
-	"fmt"
-)
-
-type FileTree interface {
-	AddPath(string, interface{}) *Node
-	RemovePath(string) error
-	Visit(Visiter) error
-	// Diff(*Tree) error
-	Stack(*Tree) (Tree, error)
-}
-
-type Visiter func(*Node) error
-
-func (tree *Tree) Visit(visiter Visiter) error {
-	return tree.root.Visit(visiter)
-}
-
-func (node *Node) Visit(visiter Visiter) error {
-	for _, child := range node.children {
-		err := child.Visit(visiter)
-		if err != nil {
-			return err
-		}
-	}
-	return visiter(node)
-}
-
-func (node *Node) IsWhiteout() bool {
-	return strings.HasPrefix(node.name, ".wh.")
-}
-
-func (node *Node) Path() string {
-	path := []string{}
-	curNode := node
-	for {
-		if curNode.parent == nil{
-			break
-		}
-		path = append([]string{curNode.name}, path...)
-		curNode = curNode.parent
-	}
-	return "/" + strings.Join(path, "/")
-}
-
-
-func (node *Node) WhiteoutPath() string {
-	path := []string{}
-	curNode := node
-	for {
-		if curNode.parent == nil{
-			break
-		}
-
-		name := curNode.name
-		if curNode == node {
-			name = strings.TrimPrefix(name, ".wh.")
-		}
-
-		path = append([]string{name}, path...)
-		curNode = curNode.parent
-	}
-	return "/" + strings.Join(path, "/")
-}
-
-
-
-func (tree *Tree) Stack(upper *Tree) (error) {
-	graft := func(node *Node) error {
-		if node.IsWhiteout() {
-			err := tree.RemovePath(node.WhiteoutPath())
-			if err != nil {
-				return fmt.Errorf("Cannot remove node %s: %v", node.Path(), err.Error())
-			}
-		} else {
-			newNode, err := tree.AddPath(node.Path(), node.data)
-			if err != nil {
-				return fmt.Errorf("Cannot add node %s: %v", newNode.Path(), err.Error())
-			}
-		}
-		return nil
-	}
-	return upper.Visit(graft)
-}
-
-func (tree *Tree) GetNode(path string) (*Node, error) {
-	nodeNames := strings.Split(path, "/")
-	node := tree.Root()
-	for _, name := range nodeNames {
-		if name == "" {
-			continue
-		}
-		if node.children[name] == nil {
-			return nil, errors.New("Path does not exist")
-		}
-		node = node.children[name]
-	}
-	return node, nil
-}
-
-func (tree *Tree) AddPath(path string, data interface{}) (*Node, error) {
-	nodeNames := strings.Split(path, "/")
-	node := tree.Root()
-	for idx, name := range nodeNames {
-		if name == "" {
-			continue
-		}
-		// find or create node
-		if node.children[name] != nil {
-			node = node.children[name]
-		} else {
-			// don't attach the payload. The payload is destined for the
-			// path's end node, not any intermediary node.
-			node = node.AddChild(name, nil)
-		}
-
-		// attach payload to the last specified node
-		if idx == len(nodeNames)-1 {
-			node.data = data
-		}
-
-	}
-	return node, nil
-}
-
-func (tree *Tree) RemovePath(path string) error {
-	node, err := tree.GetNode(path)
-	if err != nil {
-		return err
-	}
-	return node.Remove()
-}

filetree_test.go

@@ -1,141 +0,0 @@
-package main
-
-import "testing"
-
-func TestAddPath(t *testing.T) {
-	tree := NewTree()
-	tree.AddPath("/etc/nginx/nginx.conf", 1)
-	tree.AddPath("/etc/nginx/public", 2)
-	tree.AddPath("/var/run/systemd", 3)
-	tree.AddPath("/var/run/bashful", 4)
-	tree.AddPath("/tmp", 5)
-	tree.AddPath("/tmp/nonsense", 6)
-
-	expected := `.
-├── etc
-│   └── nginx
-│       ├── nginx.conf
-│       └── public
-├── tmp
-│   └── nonsense
-└── var
-    └── run
-        ├── bashful
-        └── systemd
-`
-	actual := tree.String()
-
-	if expected != actual {
-		t.Errorf("Expected tree string:\n--->%s<---\nGot:\n--->%s<---", expected, actual)
-	}
-
-}
-
-func TestRemovePath(t *testing.T) {
-	tree := NewTree()
-	tree.AddPath("/etc/nginx/nginx.conf", 1)
-	tree.AddPath("/etc/nginx/public", 2)
-	tree.AddPath("/var/run/systemd", 3)
-	tree.AddPath("/var/run/bashful", 4)
-	tree.AddPath("/tmp", 5)
-	tree.AddPath("/tmp/nonsense", 6)
-
-	tree.RemovePath("/var/run/bashful")
-	tree.RemovePath("/tmp")
-
-	expected := `.
-├── etc
-│   └── nginx
-│       ├── nginx.conf
-│       └── public
-└── var
-    └── run
-        └── systemd
-`
-	actual := tree.String()
-
-	if expected != actual {
-		t.Errorf("Expected tree string:\n--->%s<---\nGot:\n--->%s<---", expected, actual)
-	}
-
-}
-
-func TestPath(t *testing.T) {
-	expected := "/etc/nginx/nginx.conf"
-	tree := NewTree()
-	node, _ := tree.AddPath(expected, nil)
-
-	actual := node.Path()
-	if expected != actual {
-		t.Errorf("Expected path '%s' got '%s'", expected, actual)
-	}
-}
-
-func TestIsWhiteout(t *testing.T) {
-	tree1 := NewTree()
-	p1, _ := tree1.AddPath("/etc/nginx/public1", 2)
-	p2, _ := tree1.AddPath("/etc/nginx/.wh.public2", 2)
-
-	if p1.IsWhiteout() != false {
-		t.Errorf("Expected path '%s' to **not** be a whiteout file", p1.name)
-	}
-
-	if p2.IsWhiteout() != true {
-		t.Errorf("Expected path '%s' to be a whiteout file", p2.name)
-	}
-}
-
-
-func TestStack(t *testing.T) {
-	payloadKey := "/var/run/systemd"
-	payloadValue := 1263487
-
-	tree1 := NewTree()
-
-	tree1.AddPath("/etc/nginx/public", 2)
-	tree1.AddPath(payloadKey, 3)
-	tree1.AddPath("/var/run/bashful", 4)
-	tree1.AddPath("/tmp", 5)
-	tree1.AddPath("/tmp/nonsense", 6)
-
-	tree2 := NewTree()
-	// add new files
-	tree2.AddPath("/etc/nginx/nginx.conf", 1)
-	// modify current files
-	tree2.AddPath(payloadKey, payloadValue)
-	// whiteout the following files
-	tree2.AddPath("/var/run/.wh.bashful", nil)
-	tree2.AddPath("/.wh.tmp", nil)
-
-	err := tree1.Stack(tree2)
-
-	if err != nil {
-		t.Errorf("Could not stack trees: %v", err)
-	}
-
-	expected := `.
-├── etc
-│   └── nginx
-│       ├── nginx.conf
-│       └── public
-└── var
-    └── run
-        └── systemd
-`
-
-	node, err := tree1.GetNode(payloadKey)
-	if err != nil {
-		t.Errorf("Expected '%s' to still exist, but it doesn't", payloadKey)
-	}
-
-	if node.data != payloadValue {
-		t.Errorf("Expected '%s' value to be %d but got %d", payloadKey, payloadValue, node.data.(int))
-	}
-
-	actual := tree1.String()
-
-	if expected != actual {
-		t.Errorf("Expected tree string:\n--->%s<---\nGot:\n--->%s<---", expected, actual)
-	}
-
-}

tar-read.go

@@ -28,7 +28,7 @@ func main() {
 	tarReader := tar.NewReader(f)
 	targetName := "manifest.json"
 	var m Manifest
-	var trees []*Tree
+	var trees []*FileTree
 	for {
 		header, err := tarReader.Next()
 

tree.go

@@ -2,32 +2,45 @@ package main
 
 import (
 	"sort"
+	"strings"
+	"fmt"
+	"errors"
 )
 
 const (
-	newLine      = "\n"
+	newLine        = "\n"
-	emptySpace   = "    "
+	emptySpace     = "    "
-	middleItem   = "├── "
+	middleItem     = "├── "
-	continueItem = "│   "
+	continueItem   = "│   "
-	lastItem     = "└── "
+	lastItem       = "└── "
+	whiteoutPrefix = ".wh."
 )
 
-type Tree struct {
+//type FileTree interface {
+//	AddPath(string, interface{}) *Node
+//	RemovePath(string) error
+//	Visit(Visiter) error
+//	// Diff(*FileTree) error
+//	Stack(*FileTree) (FileTree, error)
+//}
+
+
+type FileTree struct {
 	root *Node
 	size int
 	name string
 }
 
 type Node struct {
-	tree     *Tree
+	tree     *FileTree
 	parent   *Node
 	name     string
 	data     interface{}
 	children map[string]*Node
 }
 
-func NewTree() (tree *Tree) {
+func NewTree() (tree *FileTree) {
-	tree = new(Tree)
+	tree = new(FileTree)
 	tree.size = 0
 	tree.root = new(Node)
 	tree.root.tree = tree
@@ -45,7 +58,7 @@ func NewNode(parent *Node, name string, data interface{}) (node *Node) {
 	return node
 }
 
-func (tree *Tree) Root() *Node {
+func (tree *FileTree) Root() *Node {
 	return tree.root
 }
 
@@ -74,7 +87,7 @@ func (node *Node) String() string {
 	return node.name
 }
 
-func (tree *Tree) String() string {
+func (tree *FileTree) String() string {
 	var renderLine func(string, []bool, bool) string
 	var walkTree func(*Node, []bool) string
 
@@ -129,7 +142,7 @@ func (node *Node) Copy() *Node {
 	return newNode
 }
 
-func (tree *Tree) Copy() *Tree {
+func (tree *FileTree) Copy() *FileTree {
 	newTree := NewTree()
 	*newTree = *tree
 	newTree.root = tree.Root().Copy()
@@ -137,3 +150,112 @@ func (tree *Tree) Copy() *Tree {
 	return newTree
 }
 
+type Visiter func(*Node) error
+
+func (tree *FileTree) Visit(visiter Visiter) error {
+	return tree.root.Visit(visiter)
+}
+
+func (node *Node) Visit(visiter Visiter) error {
+	for _, child := range node.children {
+		err := child.Visit(visiter)
+		if err != nil {
+			return err
+		}
+	}
+	return visiter(node)
+}
+
+func (node *Node) IsWhiteout() bool {
+	return strings.HasPrefix(node.name, whiteoutPrefix)
+}
+
+func (node *Node) Path() string {
+	path := []string{}
+	curNode := node
+	for {
+		if curNode.parent == nil{
+			break
+		}
+
+		name := curNode.name
+		if curNode == node {
+			// white out prefixes are fictitious on leaf nodes
+			name = strings.TrimPrefix(name, whiteoutPrefix)
+		}
+
+		path = append([]string{name}, path...)
+		curNode = curNode.parent
+	}
+	return "/" + strings.Join(path, "/")
+}
+
+
+
+func (tree *FileTree) Stack(upper *FileTree) (error) {
+	graft := func(node *Node) error {
+		if node.IsWhiteout() {
+			err := tree.RemovePath(node.Path())
+			if err != nil {
+				return fmt.Errorf("Cannot remove node %s: %v", node.Path(), err.Error())
+			}
+		} else {
+			newNode, err := tree.AddPath(node.Path(), node.data)
+			if err != nil {
+				return fmt.Errorf("Cannot add node %s: %v", newNode.Path(), err.Error())
+			}
+		}
+		return nil
+	}
+	return upper.Visit(graft)
+}
+
+func (tree *FileTree) GetNode(path string) (*Node, error) {
+	nodeNames := strings.Split(path, "/")
+	node := tree.Root()
+	for _, name := range nodeNames {
+		if name == "" {
+			continue
+		}
+		if node.children[name] == nil {
+			return nil, errors.New("Path does not exist")
+		}
+		node = node.children[name]
+	}
+	return node, nil
+}
+
+func (tree *FileTree) AddPath(path string, data interface{}) (*Node, error) {
+	nodeNames := strings.Split(path, "/")
+	node := tree.Root()
+	for idx, name := range nodeNames {
+		if name == "" {
+			continue
+		}
+		// find or create node
+		if node.children[name] != nil {
+			node = node.children[name]
+		} else {
+			// don't attach the payload. The payload is destined for the
+			// path's end node, not any intermediary node.
+			node = node.AddChild(name, nil)
+		}
+
+		// attach payload to the last specified node
+		if idx == len(nodeNames)-1 {
+			node.data = data
+		}
+
+	}
+	return node, nil
+}
+
+func (tree *FileTree) RemovePath(path string) error {
+	node, err := tree.GetNode(path)
+	if err != nil {
+		return err
+	}
+	return node.Remove()
+}
+
+

tree_test.go

@@ -95,3 +95,142 @@ func TestPrintTree(t *testing.T) {
 	}
 
 }
+
+
+func TestAddPath(t *testing.T) {
+	tree := NewTree()
+	tree.AddPath("/etc/nginx/nginx.conf", 1)
+	tree.AddPath("/etc/nginx/public", 2)
+	tree.AddPath("/var/run/systemd", 3)
+	tree.AddPath("/var/run/bashful", 4)
+	tree.AddPath("/tmp", 5)
+	tree.AddPath("/tmp/nonsense", 6)
+
+	expected := `.
+├── etc
+│   └── nginx
+│       ├── nginx.conf
+│       └── public
+├── tmp
+│   └── nonsense
+└── var
+    └── run
+        ├── bashful
+        └── systemd
+`
+	actual := tree.String()
+
+	if expected != actual {
+		t.Errorf("Expected tree string:\n--->%s<---\nGot:\n--->%s<---", expected, actual)
+	}
+
+}
+
+func TestRemovePath(t *testing.T) {
+	tree := NewTree()
+	tree.AddPath("/etc/nginx/nginx.conf", 1)
+	tree.AddPath("/etc/nginx/public", 2)
+	tree.AddPath("/var/run/systemd", 3)
+	tree.AddPath("/var/run/bashful", 4)
+	tree.AddPath("/tmp", 5)
+	tree.AddPath("/tmp/nonsense", 6)
+
+	tree.RemovePath("/var/run/bashful")
+	tree.RemovePath("/tmp")
+
+	expected := `.
+├── etc
+│   └── nginx
+│       ├── nginx.conf
+│       └── public
+└── var
+    └── run
+        └── systemd
+`
+	actual := tree.String()
+
+	if expected != actual {
+		t.Errorf("Expected tree string:\n--->%s<---\nGot:\n--->%s<---", expected, actual)
+	}
+
+}
+
+func TestPath(t *testing.T) {
+	expected := "/etc/nginx/nginx.conf"
+	tree := NewTree()
+	node, _ := tree.AddPath(expected, nil)
+
+	actual := node.Path()
+	if expected != actual {
+		t.Errorf("Expected path '%s' got '%s'", expected, actual)
+	}
+}
+
+func TestIsWhiteout(t *testing.T) {
+	tree1 := NewTree()
+	p1, _ := tree1.AddPath("/etc/nginx/public1", 2)
+	p2, _ := tree1.AddPath("/etc/nginx/.wh.public2", 2)
+
+	if p1.IsWhiteout() != false {
+		t.Errorf("Expected path '%s' to **not** be a whiteout file", p1.name)
+	}
+
+	if p2.IsWhiteout() != true {
+		t.Errorf("Expected path '%s' to be a whiteout file", p2.name)
+	}
+}
+
+
+func TestStack(t *testing.T) {
+	payloadKey := "/var/run/systemd"
+	payloadValue := 1263487
+
+	tree1 := NewTree()
+
+	tree1.AddPath("/etc/nginx/public", 2)
+	tree1.AddPath(payloadKey, 3)
+	tree1.AddPath("/var/run/bashful", 4)
+	tree1.AddPath("/tmp", 5)
+	tree1.AddPath("/tmp/nonsense", 6)
+
+	tree2 := NewTree()
+	// add new files
+	tree2.AddPath("/etc/nginx/nginx.conf", 1)
+	// modify current files
+	tree2.AddPath(payloadKey, payloadValue)
+	// whiteout the following files
+	tree2.AddPath("/var/run/.wh.bashful", nil)
+	tree2.AddPath("/.wh.tmp", nil)
+
+	err := tree1.Stack(tree2)
+
+	if err != nil {
+		t.Errorf("Could not stack trees: %v", err)
+	}
+
+	expected := `.
+├── etc
+│   └── nginx
+│       ├── nginx.conf
+│       └── public
+└── var
+    └── run
+        └── systemd
+`
+
+	node, err := tree1.GetNode(payloadKey)
+	if err != nil {
+		t.Errorf("Expected '%s' to still exist, but it doesn't", payloadKey)
+	}
+
+	if node.data != payloadValue {
+		t.Errorf("Expected '%s' value to be %d but got %d", payloadKey, payloadValue, node.data.(int))
+	}
+
+	actual := tree1.String()
+
+	if expected != actual {
+		t.Errorf("Expected tree string:\n--->%s<---\nGot:\n--->%s<---", expected, actual)
+	}
+
+}