Update lego

vendor/github.com/cpu/goacmedns/storage.go

@@ -0,0 +1,89 @@
+package goacmedns
+
+import (
+	"encoding/json"
+	"errors"
+	"io/ioutil"
+	"os"
+)
+
+// Storage is an interface describing the required functions for an ACME DNS
+// Account storage mechanism.
+type Storage interface {
+	// Save will persist the `Account` data that has been `Put` so far
+	Save() error
+	// Put will add an `Account` for the given domain to the storage. It may not
+	// be persisted until `Save` is called.
+	Put(string, Account) error
+	// Fetch will retrieve an `Account` for the given domain from the storage. If
+	// the provided domain does not have an `Account` saved in the storage
+	// `ErrDomainNotFound` will be returned
+	Fetch(string) (Account, error)
+}
+
+var (
+	// ErrDomainNotFound is returned from `Fetch` when the provided domain is not
+	// present in the storage.
+	ErrDomainNotFound = errors.New("requested domain is not present in storage")
+)
+
+// fileStorage implements the `Storage` interface and persists `Accounts` to
+// a JSON file on disk.
+type fileStorage struct {
+	// path is the filepath that the `accounts` are persisted to when the `Save`
+	// function is called.
+	path string
+	// mode is the file mode used when the `path` JSON file must be created
+	mode os.FileMode
+	// accounts holds the `Account` data that has been `Put` into the storage
+	accounts map[string]Account
+}
+
+// NewFileStorage returns a `Storage` implementation backed by JSON content
+// saved into the provided `path` on disk. The file at `path` will be created if
+// required. When creating a new file the provided `mode` is used to set the
+// permissions.
+func NewFileStorage(path string, mode os.FileMode) Storage {
+	fs := fileStorage{
+		path:     path,
+		mode:     mode,
+		accounts: make(map[string]Account),
+	}
+	// Opportunistically try to load the account data. Return an empty account if
+	// any errors occur.
+	if jsonData, err := ioutil.ReadFile(path); err == nil {
+		if err := json.Unmarshal(jsonData, &fs.accounts); err != nil {
+			return fs
+		}
+	}
+	return fs
+}
+
+// Save persists the `Account` data to the fileStorage's configured path. The
+// file at that path will be created with the fileStorage's mode if required.
+func (f fileStorage) Save() error {
+	if serialized, err := json.Marshal(f.accounts); err != nil {
+		return err
+	} else if err = ioutil.WriteFile(f.path, serialized, f.mode); err != nil {
+		return err
+	}
+	return nil
+}
+
+// Put saves an `Account` for the given `Domain` into the in-memory accounts of
+// the fileStorage instance. The `Account` data will not be written to disk
+// until the `Save` function is called
+func (f fileStorage) Put(domain string, acct Account) error {
+	f.accounts[domain] = acct
+	return nil
+}
+
+// Fetch retrieves the `Account` object for the given `domain` from the
+// fileStorage in-memory accounts. If the `domain` provided does not have an
+// `Account` in the storage an `ErrDomainNotFound` error is returned.
+func (f fileStorage) Fetch(domain string) (Account, error) {
+	if acct, exists := f.accounts[domain]; exists {
+		return acct, nil
+	}
+	return Account{}, ErrDomainNotFound
+}