resolve and pin in one step

instead of resolving all the pins first and then pinning, pin after resolving
each pin.

This:

1. Avoids storing all the nodes in memory.
2. Avoids not showing pin progress.

fixes #4122

License: MIT
Signed-off-by: Steven Allen <steven@stebalien.com>

core/corerepo/pinning.go

@@ -22,18 +22,17 @@ import (
 	uio "github.com/ipfs/go-ipfs/unixfs/io"
 
 	cid "gx/ipfs/QmNp85zy9RLrQ5oQD4hPyS39ezrrXpcaa7R4Y9kxdWQLLQ/go-cid"
-	node "gx/ipfs/QmPN7cwmpcc4DWXb4KTB9dNAJgjuPY69h3npsMfhRrQL9c/go-ipld-format"
 )
 
 func Pin(n *core.IpfsNode, ctx context.Context, paths []string, recursive bool) ([]*cid.Cid, error) {
-	dagnodes := make([]node.Node, 0)
+	out := make([]*cid.Cid, len(paths))
 
 	r := &path.Resolver{
 		DAG:         n.DAG,
 		ResolveOnce: uio.ResolveUnixfsOnce,
 	}
 
-	for _, fpath := range paths {
+	for i, fpath := range paths {
 		p, err := path.ParsePath(fpath)
 		if err != nil {
 			return nil, err
@@ -43,18 +42,11 @@ func Pin(n *core.IpfsNode, ctx context.Context, paths []string, recursive bool)
 		if err != nil {
 			return nil, fmt.Errorf("pin: %s", err)
 		}
-		dagnodes = append(dagnodes, dagnode)
-	}
-
-	var out []*cid.Cid
-	for _, dagnode := range dagnodes {
-		c := dagnode.Cid()
-
-		err := n.Pinning.Pin(ctx, dagnode, recursive)
+		err = n.Pinning.Pin(ctx, dagnode, recursive)
 		if err != nil {
 			return nil, fmt.Errorf("pin: %s", err)
 		}
-		out = append(out, c)
+		out[i] = dagnode.Cid()
 	}
 
 	err := n.Pinning.Flush()