Moves files

internal/backend/location/location.go

@@ -0,0 +1,107 @@
+// Package location implements parsing the restic repository location from a string.
+package location
+
+import (
+	"strings"
+
+	"restic/backend/b2"
+	"restic/backend/local"
+	"restic/backend/rest"
+	"restic/backend/s3"
+	"restic/backend/sftp"
+	"restic/backend/swift"
+	"restic/errors"
+)
+
+// Location specifies the location of a repository, including the method of
+// access and (possibly) credentials needed for access.
+type Location struct {
+	Scheme string
+	Config interface{}
+}
+
+type parser struct {
+	scheme string
+	parse  func(string) (interface{}, error)
+}
+
+// parsers is a list of valid config parsers for the backends. The first parser
+// is the fallback and should always be set to the local backend.
+var parsers = []parser{
+	{"b2", b2.ParseConfig},
+	{"local", local.ParseConfig},
+	{"sftp", sftp.ParseConfig},
+	{"s3", s3.ParseConfig},
+	{"swift", swift.ParseConfig},
+	{"rest", rest.ParseConfig},
+}
+
+func isPath(s string) bool {
+	if strings.HasPrefix(s, "../") || strings.HasPrefix(s, `..\`) {
+		return true
+	}
+
+	if strings.HasPrefix(s, "/") || strings.HasPrefix(s, `\`) {
+		return true
+	}
+
+	if len(s) < 3 {
+		return false
+	}
+
+	// check for drive paths
+	drive := s[0]
+	if !(drive >= 'a' && drive <= 'z') && !(drive >= 'A' && drive <= 'Z') {
+		return false
+	}
+
+	if s[1] != ':' {
+		return false
+	}
+
+	if s[2] != '\\' && s[2] != '/' {
+		return false
+	}
+
+	return true
+}
+
+// Parse extracts repository location information from the string s. If s
+// starts with a backend name followed by a colon, that backend's Parse()
+// function is called. Otherwise, the local backend is used which interprets s
+// as the name of a directory.
+func Parse(s string) (u Location, err error) {
+	scheme := extractScheme(s)
+	u.Scheme = scheme
+
+	for _, parser := range parsers {
+		if parser.scheme != scheme {
+			continue
+		}
+
+		u.Config, err = parser.parse(s)
+		if err != nil {
+			return Location{}, err
+		}
+
+		return u, nil
+	}
+
+	// if s is not a path or contains ":", it's ambiguous
+	if !isPath(s) && strings.ContainsRune(s, ':') {
+		return Location{}, errors.New("invalid backend\nIf the repo is in a local directory, you need to add a `local:` prefix")
+	}
+
+	u.Scheme = "local"
+	u.Config, err = local.ParseConfig("local:" + s)
+	if err != nil {
+		return Location{}, err
+	}
+
+	return u, nil
+}
+
+func extractScheme(s string) string {
+	data := strings.SplitN(s, ":", 2)
+	return data[0]
+}