version.go

  1package identity
  2
  3import (
  4	"crypto/rand"
  5	"encoding/json"
  6	"fmt"
  7	"strings"
  8
  9	"github.com/MichaelMure/git-bug/repository"
 10	"github.com/MichaelMure/git-bug/util/git"
 11	"github.com/MichaelMure/git-bug/util/lamport"
 12	"github.com/MichaelMure/git-bug/util/text"
 13	"github.com/pkg/errors"
 14)
 15
 16const formatVersion = 1
 17
 18// Version is a complete set of information about an Identity at a point in time.
 19type Version struct {
 20	// Not serialized
 21	commitHash git.Hash
 22
 23	// Todo: add unix timestamp for ordering with identical lamport time ?
 24
 25	// The lamport time at which this version become effective
 26	// The reference time is the bug edition lamport clock
 27	time lamport.Time
 28
 29	name      string
 30	email     string
 31	login     string
 32	avatarURL string
 33
 34	// The set of keys valid at that time, from this version onward, until they get removed
 35	// in a new version. This allow to have multiple key for the same identity (e.g. one per
 36	// device) as well as revoke key.
 37	keys []Key
 38
 39	// This optional array is here to ensure a better randomness of the identity id to avoid collisions.
 40	// It has no functional purpose and should be ignored.
 41	// It is advised to fill this array if there is not enough entropy, e.g. if there is no keys.
 42	nonce []byte
 43
 44	// A set of arbitrary key/value to store metadata about a version or about an Identity in general.
 45	metadata map[string]string
 46}
 47
 48type VersionJSON struct {
 49	// Additional field to version the data
 50	FormatVersion uint `json:"version"`
 51
 52	Time      lamport.Time      `json:"time"`
 53	Name      string            `json:"name"`
 54	Email     string            `json:"email"`
 55	Login     string            `json:"login"`
 56	AvatarUrl string            `json:"avatar_url"`
 57	Keys      []Key             `json:"pub_keys"`
 58	Nonce     []byte            `json:"nonce,omitempty"`
 59	Metadata  map[string]string `json:"metadata,omitempty"`
 60}
 61
 62func (v *Version) MarshalJSON() ([]byte, error) {
 63	return json.Marshal(VersionJSON{
 64		FormatVersion: formatVersion,
 65		Time:          v.time,
 66		Name:          v.name,
 67		Email:         v.email,
 68		Login:         v.login,
 69		AvatarUrl:     v.avatarURL,
 70		Keys:          v.keys,
 71		Nonce:         v.nonce,
 72		Metadata:      v.metadata,
 73	})
 74}
 75
 76func (v *Version) UnmarshalJSON(data []byte) error {
 77	var aux VersionJSON
 78
 79	if err := json.Unmarshal(data, &aux); err != nil {
 80		return err
 81	}
 82
 83	if aux.FormatVersion != formatVersion {
 84		return fmt.Errorf("unknown format version %v", aux.FormatVersion)
 85	}
 86
 87	v.time = aux.Time
 88	v.name = aux.Name
 89	v.email = aux.Email
 90	v.login = aux.Login
 91	v.avatarURL = aux.AvatarUrl
 92	v.keys = aux.Keys
 93	v.nonce = aux.Nonce
 94	v.metadata = aux.Metadata
 95
 96	return nil
 97}
 98
 99func (v *Version) Validate() error {
100	if text.Empty(v.name) && text.Empty(v.login) {
101		return fmt.Errorf("either name or login should be set")
102	}
103
104	if strings.Contains(v.name, "\n") {
105		return fmt.Errorf("name should be a single line")
106	}
107
108	if !text.Safe(v.name) {
109		return fmt.Errorf("name is not fully printable")
110	}
111
112	if strings.Contains(v.login, "\n") {
113		return fmt.Errorf("login should be a single line")
114	}
115
116	if !text.Safe(v.login) {
117		return fmt.Errorf("login is not fully printable")
118	}
119
120	if strings.Contains(v.email, "\n") {
121		return fmt.Errorf("email should be a single line")
122	}
123
124	if !text.Safe(v.email) {
125		return fmt.Errorf("email is not fully printable")
126	}
127
128	if v.avatarURL != "" && !text.ValidUrl(v.avatarURL) {
129		return fmt.Errorf("avatarUrl is not a valid URL")
130	}
131
132	if len(v.nonce) > 64 {
133		return fmt.Errorf("nonce is too big")
134	}
135
136	for _, k := range v.keys {
137		if err := k.Validate(); err != nil {
138			return errors.Wrap(err, "invalid key")
139		}
140	}
141
142	return nil
143}
144
145// Write will serialize and store the Version as a git blob and return
146// its hash
147func (v *Version) Write(repo repository.Repo) (git.Hash, error) {
148	// make sure we don't write invalid data
149	err := v.Validate()
150	if err != nil {
151		return "", errors.Wrap(err, "validation error")
152	}
153
154	data, err := json.Marshal(v)
155
156	if err != nil {
157		return "", err
158	}
159
160	hash, err := repo.StoreData(data)
161
162	if err != nil {
163		return "", err
164	}
165
166	return hash, nil
167}
168
169func makeNonce(len int) []byte {
170	result := make([]byte, len)
171	_, err := rand.Read(result)
172	if err != nil {
173		panic(err)
174	}
175	return result
176}
177
178// SetMetadata store arbitrary metadata about a version or an Identity in general
179// If the Version has been commit to git already, it won't be overwritten.
180func (v *Version) SetMetadata(key string, value string) {
181	if v.metadata == nil {
182		v.metadata = make(map[string]string)
183	}
184
185	v.metadata[key] = value
186}
187
188// GetMetadata retrieve arbitrary metadata about the Version
189func (v *Version) GetMetadata(key string) (string, bool) {
190	val, ok := v.metadata[key]
191	return val, ok
192}
193
194// AllMetadata return all metadata for this Identity
195func (v *Version) AllMetadata() map[string]string {
196	return v.metadata
197}