accounts, cmd, internal, mobile, node: canonical account URLs

accounts/url.go

@@ -0,0 +1,79 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package accounts
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+)
+
+// URL represents the canonical identification URL of a wallet or account.
+//
+// It is a simplified version of url.URL, with the important limitations (which
+// are considered features here) that it contains value-copyable components only,
+// as well as that it doesn't do any URL encoding/decoding of special characters.
+//
+// The former is important to allow an account to be copied without leaving live
+// references to the original version, whereas the latter is important to ensure
+// one single canonical form opposed to many allowed ones by the RFC 3986 spec.
+//
+// As such, these URLs should not be used outside of the scope of an Ethereum
+// wallet or account.
+type URL struct {
+	Scheme string // Protocol scheme to identify a capable account backend
+	Path   string // Path for the backend to identify a unique entity
+}
+
+// parseURL converts a user supplied URL into the accounts specific structure.
+func parseURL(url string) (URL, error) {
+	parts := strings.Split(url, "://")
+	if len(parts) != 2 || parts[0] == "" {
+		return URL{}, errors.New("protocol scheme missing")
+	}
+	return URL{
+		Scheme: parts[0],
+		Path:   parts[1],
+	}, nil
+}
+
+// String implements the stringer interface.
+func (u URL) String() string {
+	if u.Scheme != "" {
+		return fmt.Sprintf("%s://%s", u.Scheme, u.Path)
+	}
+	return u.Path
+}
+
+// MarshalJSON implements the json.Marshaller interface.
+func (u URL) MarshalJSON() ([]byte, error) {
+	return json.Marshal(u.String())
+}
+
+// Cmp compares x and y and returns:
+//
+//   -1 if x <  y
+//    0 if x == y
+//   +1 if x >  y
+//
+func (u URL) Cmp(url URL) int {
+	if u.Scheme == url.Scheme {
+		return strings.Compare(u.Path, url.Path)
+	}
+	return strings.Compare(u.Scheme, url.Scheme)
+}