ipfs · Jun 20, 2015 · Jun 20, 2015 · Jun 20, 2015 · Jun 20, 2015
Showing with 149 additions and 42 deletions.

+79 −28 core/commands/object.go

+70 −14 test/sharness/t0051-object.sh
diff --git a/core/commands/object.go b/core/commands/object.go
@@ -431,9 +431,31 @@ var objectPatchCmd = &cmds.Command{
 	Helptext: cmds.HelpText{
 		Tagline: "Create a new merkledag object based on an existing one",
 		ShortDescription: `
-'ipfs object patch <root> [add-link|rm-link] <args>' is a plumbing command used to
-build custom DAG objects. It adds and removes links from objects, creating a new
-object as a result. This is the merkle-dag version of modifying an object.
+'ipfs object patch <root> [action] <args>' is a plumbing command used
+to build custom DAG objects. It adds and removes links from objects or
+manipulates their data, creating new objects as a result. This is the
+merkle-dag version of modifying an object.
+
+Actions and their expected arguments:
+
+    * add-link PATH LINK_HASH
+      Creates a new link referencing LINK_HASH named after the final
+      segment of PATH and bubbles the Merkle node changes up the path
+      to return the new root. If some intermediate nodes in PATH are
+      missing, add-link will automatically create new nodes for them.
+    * rm-link PATH
+      Removes any links named after the final segment of PATH and
+      bubbles the Merkle node changes up the path to return the new
+      root.
+    * set-data BINARY_DATA
+      Set the root node's data to BINARY_DATA.
+    * append-data BINARY_DATA
+      Append BINARY_DATA to the root node's existing data.
+
+The nodes auto-created by add-link are basic Merkle nodes, not the
+directory nodes used for filesystem entries.  To auto-create those
+you'd need a filesystem-level version of the patch command (which
+hasn't been written yet).
 
 Examples:
 
@@ -529,7 +551,7 @@ resulting object hash.
 
 func appendDataCaller(req cmds.Request, root *dag.Node) (key.Key, error) {
 	if len(req.Arguments()) < 3 {
-		return "", fmt.Errorf("not enough arguments for set-data")
+		return "", fmt.Errorf("not enough arguments for append-data")
 	}
 
 	nd, err := req.Context().GetNode()
@@ -577,19 +599,15 @@ func rmLinkCaller(req cmds.Request, root *dag.Node) (key.Key, error) {
 		return "", err
 	}
 
-	name := req.Arguments()[2]
-
-	err = root.RemoveNodeLink(name)
-	if err != nil {
-		return "", err
-	}
+	ctx := req.Context().Context
+	path := req.Arguments()[2]
+	parts := strings.Split(path, "/")
 
-	newkey, err := nd.DAG.Add(root)
+	newRoot, err := insertNodeAtPath(ctx, nd.DAG, root, parts, nil)
 	if err != nil {
 		return "", err
 	}
-
-	return newkey, nil
+	return newRoot.Key()
 }
 
 func addLinkCaller(req cmds.Request, root *dag.Node) (key.Key, error) {
@@ -602,12 +620,18 @@ func addLinkCaller(req cmds.Request, root *dag.Node) (key.Key, error) {
 		return "", err
 	}
 
+	ctx := req.Context().Context
 	path := req.Arguments()[2]
-	childk := key.B58KeyDecode(req.Arguments()[3])
+	insertk := key.B58KeyDecode(req.Arguments()[3])
+
+	toinsert, err := nd.DAG.Get(ctx, insertk)
+	if err != nil {
+		return "", err
+	}
 
 	parts := strings.Split(path, "/")
 
-	nnode, err := insertNodeAtPath(req.Context().Context, nd.DAG, root, parts, childk)
+	nnode, err := insertNodeAtPath(ctx, nd.DAG, root, parts, toinsert)
 	if err != nil {
 		return "", err
 	}
@@ -635,32 +659,59 @@ func addLink(ctx context.Context, ds dag.DAGService, root *dag.Node, childname s
 	return root, nil
 }
 
-func insertNodeAtPath(ctx context.Context, ds dag.DAGService, root *dag.Node, path []string, toinsert key.Key) (*dag.Node, error) {
+// insertNodeAtPath follows the relative 'path' from 'root', creating
+// empty nodes as needed, and adjusts the final link to reference
+// 'toinsert'.  Then it bubbles that change back up 'path', returning
+// the new root.  If 'toinsert' is nil, the final path segment will be
+// removed, and that change will be bubbled up to a new root.
+//
+// This mutates the in-memory root *dag.Node, but the immutable DAG
+// service will contain both the original objects (e.g. root, a, b,
+// and c) and the new objects (e.g. root', a', b', and c') so
+// <root>/a/b/c will reference the old content (if there was any) and
+// <root'>/a/b/c will reference the inserted content.
+func insertNodeAtPath(ctx context.Context, ds dag.DAGService, root *dag.Node, path []string, toinsert *dag.Node) (*dag.Node, error) {
 	if len(path) == 1 {
-		return addLink(ctx, ds, root, path[0], toinsert)
-	}
-
-	child, err := root.GetNodeLink(path[0])
-	if err != nil {
-		return nil, err
+		if toinsert == nil {
+			err := root.RemoveNodeLink(path[0])
+			if err != nil {
+				return nil, err
+			}
+		} else {
+			err := root.AddNodeLinkClean(path[0], toinsert)
+			if err != nil {
+				return nil, err
+			}
+		}
+		_, err := ds.Add(root)
+		if err != nil {
+			return nil, err
+		}
+		return root, nil
 	}
 
-	nd, err := child.GetNode(ctx, ds)
-	if err != nil {
-		return nil, err
+	link, err := root.GetNodeLink(path[0])
+	var child *dag.Node
+	if err == nil {
+		child, err = link.GetNode(ctx, ds)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		child = new(dag.Node)
 	}
 
-	ndprime, err := insertNodeAtPath(ctx, ds, nd, path[1:], toinsert)
+	newChild, err := insertNodeAtPath(ctx, ds, child, path[1:], toinsert)
 	if err != nil {
 		return nil, err
 	}
 
 	err = root.RemoveNodeLink(path[0])
-	if err != nil {
+	if err != nil && err != dag.ErrNotFound {
 		return nil, err
 	}
 
-	err = root.AddNodeLinkClean(path[0], ndprime)
+	err = root.AddNodeLinkClean(path[0], newChild)
 	if err != nil {
 		return nil, err
 	}

diff --git a/test/sharness/t0051-object.sh b/test/sharness/t0051-object.sh
@@ -100,20 +100,6 @@ test_object_cmd() {
 		OUTPUT=$(ipfs object patch $EMPTY_DIR add-link foo $EMPTY_DIR)
 	'
 
-	test_expect_success "multilayer ipfs patch works" '
-		echo "hello world" > hwfile &&
-		FILE=$(ipfs add -q hwfile) &&
-		EMPTY=$(ipfs object new unixfs-dir) &&
-		ONE=$(ipfs object patch $EMPTY add-link b $EMPTY) &&
-		TWO=$(ipfs object patch $EMPTY add-link a $ONE) &&
-		ipfs object patch $TWO add-link a/b/c $FILE > multi_patch
-	'
-
-	test_expect_success "output looks good" '
-		ipfs cat $(cat multi_patch)/a/b/c > hwfile_out &&
-		test_cmp hwfile hwfile_out
-	'
-
 	test_expect_success "should have created dir within a dir" '
 		ipfs ls $OUTPUT > patched_output
 	'
@@ -131,6 +117,76 @@ test_object_cmd() {
 		echo QmUNLLsPACCz1vLxQVkXqqLX5R1X345qqfHbsf67hvA3Nn > rmlink_exp &&
 		test_cmp rmlink_exp rmlink_output
 	'
+
+	test_expect_success "multilayer patch add-link auto-creates directories" '
+		echo "hello world" > hwfile &&
+		FILE=$(ipfs add -q hwfile) &&
+		EMPTY=$(ipfs object new unixfs-dir) &&
+		ipfs object patch $EMPTY add-link a/b/c $FILE >multi_patch_add_auto_create_directories
+	'
+
+	test_expect_success "multilayer patch add-link auto-create leaf looks good" '
+		ipfs cat $(cat multi_patch_add_auto_create_directories)/a/b/c >multi_patch_add_auto_create_leaf &&
+		test_cmp hwfile multi_patch_add_auto_create_leaf
+	'
+
+	test_expect_success "multilayer patch add-link auto-create intermediate looks good" '
+		cat <<-\EOF >multi_patch_add_auto_create_intermediate_expected_newline &&
+			{
+			  "Links": [
+			    {
+			      "Name": "c",
+			      "Hash": "QmT78zSuBmuS4z925WZfrqQ1qHaJ56DQaTfyMUF7F8ff5o",
+			      "Size": 20
+			    }
+			  ],
+			  "Data": ""
+			}
+		EOF
+		printf %s "$(cat multi_patch_add_auto_create_intermediate_expected_newline)" >multi_patch_add_auto_create_intermediate_expected &&
+		ipfs object get $(cat multi_patch_add_auto_create_directories)/a/b >multi_patch_add_auto_create_intermediate &&
+		test_cmp multi_patch_add_auto_create_intermediate_expected multi_patch_add_auto_create_intermediate
+	'
+
+	test_expect_success "multilayer patch add works" '
+		echo "hello world" > hwfile &&
+		FILE=$(ipfs add -q hwfile) &&
+		EMPTY=$(ipfs object new unixfs-dir) &&
+		ONE=$(ipfs object patch $EMPTY add-link b $EMPTY) &&
+		TWO=$(ipfs object patch $EMPTY add-link a $ONE) &&
+		ipfs object patch $TWO add-link a/b/c $FILE > multi_patch
+	'
+
+	test_expect_success "multilayer patch add leaf looks good" '
+		ipfs cat $(cat multi_patch)/a/b/c > hwfile_out &&
+		test_cmp hwfile hwfile_out
+	'
+
+	test_expect_success "multilayer patch rm-link works" '
+		echo "hello world" > hwfile &&
+		FILE=$(ipfs add -q hwfile) &&
+		EMPTY=$(ipfs object new unixfs-dir) &&
+		ROOT=$(ipfs object patch $EMPTY add-link a/b/c/d $FILE) &&
+		ipfs object patch $ROOT rm-link a/b/c >multi_patch_remove
+	'
+
+	test_expect_success "multilayer patch rm-link looks good" '
+		cat <<-\EOF >multi_patch_remove_expected_newline &&
+			{
+			  "Links": [
+			    {
+			      "Name": "c",
+			      "Hash": "QmT78zSuBmuS4z925WZfrqQ1qHaJ56DQaTfyMUF7F8ff5o",
+			      "Size": 20
+			    }
+			  ],
+			  "Data": ""
+			}
+		EOF
+		printf %s "$(cat multi_patch_remove_expected_newline)" >multi_patch_remove_expected &&
+		ipfs object get $(cat multi_patch_remove)/a/b > multi_patch_remove_actual &&
+		test_cmp hwfile hwfile_out
+	'
 }
 
 # should work offline