forgejo-federation/models/avatars/avatar.go
wxiaoguang 9f8d59858a
Refactor system setting (#27000)
This PR reduces the complexity of the system setting system.

It only needs one line to introduce a new option, and the option can be
used anywhere out-of-box.

It is still high-performant (and more performant) because the config
values are cached in the config system.
2023-10-05 09:08:19 +08:00

235 lines
7.5 KiB
Go

// Copyright 2021 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package avatars
import (
"context"
"fmt"
"net/url"
"path"
"strconv"
"strings"
"sync/atomic"
"code.gitea.io/gitea/models/db"
"code.gitea.io/gitea/modules/base"
"code.gitea.io/gitea/modules/cache"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
"strk.kbt.io/projects/go/libravatar"
)
const (
// DefaultAvatarClass is the default class of a rendered avatar
DefaultAvatarClass = "ui avatar gt-vm"
// DefaultAvatarPixelSize is the default size in pixels of a rendered avatar
DefaultAvatarPixelSize = 28
)
// EmailHash represents a pre-generated hash map (mainly used by LibravatarURL, it queries email server's DNS records)
type EmailHash struct {
Hash string `xorm:"pk varchar(32)"`
Email string `xorm:"UNIQUE NOT NULL"`
}
func init() {
db.RegisterModel(new(EmailHash))
}
type avatarSettingStruct struct {
defaultAvatarLink string
gravatarSource string
gravatarSourceURL *url.URL
libravatar *libravatar.Libravatar
}
var avatarSettingAtomic atomic.Pointer[avatarSettingStruct]
func loadAvatarSetting() (*avatarSettingStruct, error) {
s := avatarSettingAtomic.Load()
if s == nil || s.gravatarSource != setting.GravatarSource {
s = &avatarSettingStruct{}
u, err := url.Parse(setting.AppSubURL)
if err != nil {
return nil, fmt.Errorf("unable to parse AppSubURL: %w", err)
}
u.Path = path.Join(u.Path, "/assets/img/avatar_default.png")
s.defaultAvatarLink = u.String()
s.gravatarSourceURL, err = url.Parse(setting.GravatarSource)
if err != nil {
return nil, fmt.Errorf("unable to parse GravatarSource %q: %w", setting.GravatarSource, err)
}
s.libravatar = libravatar.New()
if s.gravatarSourceURL.Scheme == "https" {
s.libravatar.SetUseHTTPS(true)
s.libravatar.SetSecureFallbackHost(s.gravatarSourceURL.Host)
} else {
s.libravatar.SetUseHTTPS(false)
s.libravatar.SetFallbackHost(s.gravatarSourceURL.Host)
}
avatarSettingAtomic.Store(s)
}
return s, nil
}
// DefaultAvatarLink the default avatar link
func DefaultAvatarLink() string {
a, err := loadAvatarSetting()
if err != nil {
log.Error("Failed to loadAvatarSetting: %v", err)
return ""
}
return a.defaultAvatarLink
}
// HashEmail hashes email address to MD5 string. https://en.gravatar.com/site/implement/hash/
func HashEmail(email string) string {
return base.EncodeMD5(strings.ToLower(strings.TrimSpace(email)))
}
// GetEmailForHash converts a provided md5sum to the email
func GetEmailForHash(md5Sum string) (string, error) {
return cache.GetString("Avatar:"+md5Sum, func() (string, error) {
emailHash := EmailHash{
Hash: strings.ToLower(strings.TrimSpace(md5Sum)),
}
_, err := db.GetEngine(db.DefaultContext).Get(&emailHash)
return emailHash.Email, err
})
}
// LibravatarURL returns the URL for the given email. Slow due to the DNS lookup.
// This function should only be called if a federated avatar service is enabled.
func LibravatarURL(email string) (*url.URL, error) {
a, err := loadAvatarSetting()
if err != nil {
return nil, err
}
urlStr, err := a.libravatar.FromEmail(email)
if err != nil {
log.Error("LibravatarService.FromEmail(email=%s): error %v", email, err)
return nil, err
}
u, err := url.Parse(urlStr)
if err != nil {
log.Error("Failed to parse libravatar url(%s): error %v", urlStr, err)
return nil, err
}
return u, nil
}
// saveEmailHash returns an avatar link for a provided email,
// the email and hash are saved into database, which will be used by GetEmailForHash later
func saveEmailHash(email string) string {
lowerEmail := strings.ToLower(strings.TrimSpace(email))
emailHash := HashEmail(lowerEmail)
_, _ = cache.GetString("Avatar:"+emailHash, func() (string, error) {
emailHash := &EmailHash{
Email: lowerEmail,
Hash: emailHash,
}
// OK we're going to open a session just because I think that that might hide away any problems with postgres reporting errors
if err := db.WithTx(db.DefaultContext, func(ctx context.Context) error {
has, err := db.GetEngine(ctx).Where("email = ? AND hash = ?", emailHash.Email, emailHash.Hash).Get(new(EmailHash))
if has || err != nil {
// Seriously we don't care about any DB problems just return the lowerEmail - we expect the transaction to fail most of the time
return nil
}
_, _ = db.GetEngine(ctx).Insert(emailHash)
return nil
}); err != nil {
// Seriously we don't care about any DB problems just return the lowerEmail - we expect the transaction to fail most of the time
return lowerEmail, nil
}
return lowerEmail, nil
})
return emailHash
}
// GenerateUserAvatarFastLink returns a fast link (302) to the user's avatar: "/user/avatar/${User.Name}/${size}"
func GenerateUserAvatarFastLink(userName string, size int) string {
if size < 0 {
size = 0
}
return setting.AppSubURL + "/user/avatar/" + url.PathEscape(userName) + "/" + strconv.Itoa(size)
}
// GenerateUserAvatarImageLink returns a link for `User.Avatar` image file: "/avatars/${User.Avatar}"
func GenerateUserAvatarImageLink(userAvatar string, size int) string {
if size > 0 {
return setting.AppSubURL + "/avatars/" + url.PathEscape(userAvatar) + "?size=" + strconv.Itoa(size)
}
return setting.AppSubURL + "/avatars/" + url.PathEscape(userAvatar)
}
// generateRecognizedAvatarURL generate a recognized avatar (Gravatar/Libravatar) URL, it modifies the URL so the parameter is passed by a copy
func generateRecognizedAvatarURL(u url.URL, size int) string {
urlQuery := u.Query()
urlQuery.Set("d", "identicon")
if size > 0 {
urlQuery.Set("s", strconv.Itoa(size))
}
u.RawQuery = urlQuery.Encode()
return u.String()
}
// generateEmailAvatarLink returns a email avatar link.
// if final is true, it may use a slow path (eg: query DNS).
// if final is false, it always uses a fast path.
func generateEmailAvatarLink(ctx context.Context, email string, size int, final bool) string {
email = strings.TrimSpace(email)
if email == "" {
return DefaultAvatarLink()
}
avatarSetting, err := loadAvatarSetting()
if err != nil {
return DefaultAvatarLink()
}
enableFederatedAvatar := setting.Config().Picture.EnableFederatedAvatar.Value(ctx)
if enableFederatedAvatar {
emailHash := saveEmailHash(email)
if final {
// for final link, we can spend more time on slow external query
var avatarURL *url.URL
if avatarURL, err = LibravatarURL(email); err != nil {
return DefaultAvatarLink()
}
return generateRecognizedAvatarURL(*avatarURL, size)
}
// for non-final link, we should return fast (use a 302 redirection link)
urlStr := setting.AppSubURL + "/avatar/" + url.PathEscape(emailHash)
if size > 0 {
urlStr += "?size=" + strconv.Itoa(size)
}
return urlStr
}
disableGravatar := setting.Config().Picture.DisableGravatar.Value(ctx)
if !disableGravatar {
// copy GravatarSourceURL, because we will modify its Path.
avatarURLCopy := *avatarSetting.gravatarSourceURL
avatarURLCopy.Path = path.Join(avatarURLCopy.Path, HashEmail(email))
return generateRecognizedAvatarURL(avatarURLCopy, size)
}
return DefaultAvatarLink()
}
// GenerateEmailAvatarFastLink returns a avatar link (fast, the link may be a delegated one: "/avatar/${hash}")
func GenerateEmailAvatarFastLink(ctx context.Context, email string, size int) string {
return generateEmailAvatarLink(ctx, email, size, false)
}
// GenerateEmailAvatarFinalLink returns a avatar final link (maybe slow)
func GenerateEmailAvatarFinalLink(ctx context.Context, email string, size int) string {
return generateEmailAvatarLink(ctx, email, size, true)
}