traefik/vendor/github.com/cpu/goacmedns/storage.go
2018-07-23 17:30:03 +02:00

90 lines
3 KiB
Go

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
}