git-bug/identity/version.go
2020-02-08 17:19:57 +01:00

213 lines
5.1 KiB
Go

package identity
import (
"crypto/rand"
"encoding/json"
"fmt"
"strings"
"github.com/MichaelMure/git-bug/repository"
"github.com/MichaelMure/git-bug/util/git"
"github.com/MichaelMure/git-bug/util/lamport"
"github.com/MichaelMure/git-bug/util/text"
"github.com/pkg/errors"
)
const formatVersion = 1
// Version is a complete set of information about an Identity at a point in time.
type Version struct {
// The lamport time at which this version become effective
// The reference time is the bug edition lamport clock
// It must be the first field in this struct due to https://github.com/golang/go/issues/599
time lamport.Time
unixTime int64
name string
email string // as defined in git, not for bridges
avatarURL string
// The set of keys valid at that time, from this version onward, until they get removed
// in a new version. This allow to have multiple key for the same identity (e.g. one per
// device) as well as revoke key.
keys []*Key
// This optional array is here to ensure a better randomness of the identity id to avoid collisions.
// It has no functional purpose and should be ignored.
// It is advised to fill this array if there is not enough entropy, e.g. if there is no keys.
nonce []byte
// A set of arbitrary key/value to store metadata about a version or about an Identity in general.
metadata map[string]string
// Not serialized
commitHash git.Hash
}
type VersionJSON struct {
// Additional field to version the data
FormatVersion uint `json:"version"`
Time lamport.Time `json:"time"`
UnixTime int64 `json:"unix_time"`
Name string `json:"name,omitempty"`
Email string `json:"email,omitempty"`
AvatarUrl string `json:"avatar_url,omitempty"`
Keys []*Key `json:"pub_keys,omitempty"`
Nonce []byte `json:"nonce,omitempty"`
Metadata map[string]string `json:"metadata,omitempty"`
}
// Make a deep copy
func (v *Version) Clone() *Version {
clone := &Version{
name: v.name,
email: v.email,
avatarURL: v.avatarURL,
keys: make([]*Key, len(v.keys)),
}
for i, key := range v.keys {
clone.keys[i] = key.Clone()
}
return clone
}
func (v *Version) MarshalJSON() ([]byte, error) {
return json.Marshal(VersionJSON{
FormatVersion: formatVersion,
Time: v.time,
UnixTime: v.unixTime,
Name: v.name,
Email: v.email,
AvatarUrl: v.avatarURL,
Keys: v.keys,
Nonce: v.nonce,
Metadata: v.metadata,
})
}
func (v *Version) UnmarshalJSON(data []byte) error {
var aux VersionJSON
if err := json.Unmarshal(data, &aux); err != nil {
return err
}
if aux.FormatVersion != formatVersion {
return fmt.Errorf("unknown format version %v", aux.FormatVersion)
}
v.time = aux.Time
v.unixTime = aux.UnixTime
v.name = aux.Name
v.email = aux.Email
v.avatarURL = aux.AvatarUrl
v.keys = aux.Keys
v.nonce = aux.Nonce
v.metadata = aux.Metadata
return nil
}
func (v *Version) Validate() error {
// time must be set after a commit
if v.commitHash != "" && v.unixTime == 0 {
return fmt.Errorf("unix time not set")
}
if v.commitHash != "" && v.time == 0 {
return fmt.Errorf("lamport time not set")
}
if text.Empty(v.name) {
return fmt.Errorf("name not set")
}
if strings.Contains(v.name, "\n") {
return fmt.Errorf("name should be a single line")
}
if !text.Safe(v.name) {
return fmt.Errorf("name is not fully printable")
}
if strings.Contains(v.email, "\n") {
return fmt.Errorf("email should be a single line")
}
if !text.Safe(v.email) {
return fmt.Errorf("email is not fully printable")
}
if v.avatarURL != "" && !text.ValidUrl(v.avatarURL) {
return fmt.Errorf("avatarUrl is not a valid URL")
}
if len(v.nonce) > 64 {
return fmt.Errorf("nonce is too big")
}
for _, k := range v.keys {
if err := k.Validate(); err != nil {
return errors.Wrap(err, "invalid key")
}
}
return nil
}
// Write will serialize and store the Version as a git blob and return
// its hash
func (v *Version) Write(repo repository.Repo) (git.Hash, error) {
// make sure we don't write invalid data
err := v.Validate()
if err != nil {
return "", errors.Wrap(err, "validation error")
}
data, err := json.Marshal(v)
if err != nil {
return "", err
}
hash, err := repo.StoreData(data)
if err != nil {
return "", err
}
return hash, nil
}
func makeNonce(len int) []byte {
result := make([]byte, len)
_, err := rand.Read(result)
if err != nil {
panic(err)
}
return result
}
// SetMetadata store arbitrary metadata about a version or an Identity in general
// If the Version has been commit to git already, it won't be overwritten.
func (v *Version) SetMetadata(key string, value string) {
if v.metadata == nil {
v.metadata = make(map[string]string)
}
v.metadata[key] = value
}
// GetMetadata retrieve arbitrary metadata about the Version
func (v *Version) GetMetadata(key string) (string, bool) {
val, ok := v.metadata[key]
return val, ok
}
// AllMetadata return all metadata for this Version
func (v *Version) AllMetadata() map[string]string {
return v.metadata
}