GoBlog/webmention.go

320 lines
8.9 KiB
Go

package main
import (
"database/sql"
"errors"
"fmt"
"net/http"
"strings"
"time"
"go.goblog.app/app/pkgs/bufferpool"
"go.goblog.app/app/pkgs/contenttype"
)
type webmentionStatus string
const (
webmentionStatusVerified webmentionStatus = "verified"
webmentionStatusApproved webmentionStatus = "approved"
webmentionPath = "/webmention"
)
type mention struct {
ID int
Source string
NewSource string
Target string
NewTarget string
Url string
Created int64
Title string
Content string
Author string
Status webmentionStatus
Submentions []*mention
hasUrl bool
}
func (a *goBlog) initWebmention() {
// Add hooks
hookFunc := func(p *post) {
_ = a.sendWebmentions(p)
}
a.pPostHooks = append(a.pPostHooks, hookFunc)
a.pUpdateHooks = append(a.pUpdateHooks, hookFunc)
a.pDeleteHooks = append(a.pDeleteHooks, hookFunc)
a.pUndeleteHooks = append(a.pUndeleteHooks, hookFunc)
// Start verifier
a.initWebmentionQueue()
}
func (a *goBlog) handleWebmention(w http.ResponseWriter, r *http.Request) {
m, err := a.extractMention(r)
if err != nil {
a.debug("Error extracting webmention:", err.Error())
a.serveError(w, r, err.Error(), http.StatusBadRequest)
return
}
hasShortPrefix := a.cfg.Server.ShortPublicAddress != "" && strings.HasPrefix(m.Target, a.cfg.Server.ShortPublicAddress)
hasLongPrefix := strings.HasPrefix(m.Target, a.cfg.Server.PublicAddress)
if !hasShortPrefix && !hasLongPrefix {
a.debug("Webmention target not allowed:", m.Target)
a.serveError(w, r, "target not allowed", http.StatusBadRequest)
return
}
if m.Target == m.Source {
a.debug("Webmention target and source are the same:", m.Target)
a.serveError(w, r, "target and source are the same", http.StatusBadRequest)
return
}
if err = a.queueMention(m); err != nil {
a.debug("Failed to queue webmention", err.Error())
a.serveError(w, r, err.Error(), http.StatusInternalServerError)
return
}
w.WriteHeader(http.StatusAccepted)
_, _ = fmt.Fprint(w, "Webmention accepted")
a.debug("Accepted webmention:", m.Source, m.Target)
}
func (a *goBlog) extractMention(r *http.Request) (*mention, error) {
if ct := r.Header.Get(contentType); !strings.Contains(ct, contenttype.WWWForm) {
a.debug("New webmention request with wrong content type:", ct)
return nil, errors.New("unsupported Content-Type")
}
err := r.ParseForm()
if err != nil {
return nil, err
}
source := r.Form.Get("source")
target := unescapedPath(r.Form.Get("target"))
if source == "" || target == "" || !isAbsoluteURL(source) || !isAbsoluteURL(target) {
a.debug("Invalid webmention request, source:", source, "target:", target)
return nil, errors.New("invalid request")
}
return &mention{
Source: source,
Target: target,
Created: time.Now().Unix(),
}, nil
}
func (db *database) webmentionExists(m *mention) bool {
result := 0
row, err := db.queryRow(
`
select exists(
select 1
from webmentions
where
lowerx(source) in (lowerx(@source), lowerx(@newsource))
and lowerx(target) in (lowerx(@target), lowerx(@newtarget))
)
`,
sql.Named("source", m.Source), sql.Named("newsource", defaultIfEmpty(m.NewSource, m.Source)),
sql.Named("target", m.Target), sql.Named("newtarget", defaultIfEmpty(m.NewTarget, m.Target)),
)
if err != nil {
return false
}
if err = row.Scan(&result); err != nil {
return false
}
return result == 1
}
func (a *goBlog) createWebmention(source, target string) (err error) {
return a.queueMention(&mention{
Source: source,
Target: unescapedPath(target),
Created: time.Now().Unix(),
})
}
func (db *database) insertWebmention(m *mention, status webmentionStatus) error {
_, err := db.exec(
`
insert into webmentions (source, target, url, created, status, title, content, author)
values (@source, @target, @url, @created, @status, @title, @content, @author)
`,
sql.Named("source", m.Source),
sql.Named("target", m.Target),
sql.Named("url", m.Url),
sql.Named("created", m.Created),
sql.Named("status", status),
sql.Named("title", m.Title),
sql.Named("content", m.Content),
sql.Named("author", m.Author),
)
return err
}
func (db *database) updateWebmention(m *mention, newStatus webmentionStatus) error {
_, err := db.exec(`
update webmentions
set
source = @newsource,
target = @newtarget,
url = @url,
status = @status,
title = @title,
content = @content,
author = @author
where
lowerx(source) in (lowerx(@source), lowerx(@newsource2))
and lowerx(target) in (lowerx(@target), lowerx(@newtarget2))
`,
sql.Named("newsource", defaultIfEmpty(m.NewSource, m.Source)),
sql.Named("newtarget", defaultIfEmpty(m.NewTarget, m.Target)),
sql.Named("url", m.Url),
sql.Named("status", newStatus),
sql.Named("title", m.Title),
sql.Named("content", m.Content),
sql.Named("author", m.Author),
sql.Named("source", m.Source),
sql.Named("newsource2", defaultIfEmpty(m.NewSource, m.Source)),
sql.Named("target", m.Target),
sql.Named("newtarget2", defaultIfEmpty(m.NewTarget, m.Target)),
)
return err
}
func (db *database) deleteWebmentionId(id int) error {
_, err := db.exec("delete from webmentions where id = @id", sql.Named("id", id))
return err
}
func (db *database) deleteWebmention(m *mention) error {
_, err := db.exec(
"delete from webmentions where lowerx(source) in (lowerx(@source), lowerx(@newsource)) and lowerx(target) in (lowerx(@target), lowerx(@newtarget))",
sql.Named("source", m.Source),
sql.Named("newsource", defaultIfEmpty(m.NewSource, m.Source)),
sql.Named("target", m.Target),
sql.Named("newtarget", defaultIfEmpty(m.NewTarget, m.Target)),
)
return err
}
func (db *database) approveWebmentionId(id int) error {
_, err := db.exec("update webmentions set status = ? where id = ?", webmentionStatusApproved, id)
return err
}
func (a *goBlog) reverifyWebmentionId(id int) error {
m, err := a.db.getWebmentions(&webmentionsRequestConfig{
id: id,
limit: 1,
})
if err != nil {
return err
}
if len(m) > 0 {
err = a.queueMention(m[0])
}
return err
}
type webmentionsRequestConfig struct {
target string
status webmentionStatus
sourcelike string
id int
asc bool
offset, limit int
submentions bool
}
func buildWebmentionsQuery(config *webmentionsRequestConfig) (query string, args []any) {
queryBuilder := bufferpool.Get()
defer bufferpool.Put(queryBuilder)
queryBuilder.WriteString("select id, source, target, url, created, title, content, author, status from webmentions ")
if config != nil {
queryBuilder.WriteString("where 1")
if config.target != "" {
queryBuilder.WriteString(" and lowerx(target) = lowerx(@target)")
args = append(args, sql.Named("target", config.target))
}
if config.status != "" {
queryBuilder.WriteString(" and status = @status")
args = append(args, sql.Named("status", config.status))
}
if config.sourcelike != "" {
queryBuilder.WriteString(" and lowerx(source) like ('%' || lowerx(@sourcelike) || '%')")
args = append(args, sql.Named("sourcelike", config.sourcelike))
}
if config.id != 0 {
queryBuilder.WriteString(" and id = @id")
args = append(args, sql.Named("id", config.id))
}
}
queryBuilder.WriteString(" order by created ")
if config.asc {
queryBuilder.WriteString("asc")
} else {
queryBuilder.WriteString("desc")
}
if config.limit != 0 || config.offset != 0 {
queryBuilder.WriteString(" limit @limit offset @offset")
args = append(args, sql.Named("limit", config.limit), sql.Named("offset", config.offset))
}
return queryBuilder.String(), args
}
func (db *database) getWebmentions(config *webmentionsRequestConfig) ([]*mention, error) {
mentions := []*mention{}
query, args := buildWebmentionsQuery(config)
rows, err := db.query(query, args...)
if err != nil {
return nil, err
}
for rows.Next() {
m := &mention{}
err = rows.Scan(&m.ID, &m.Source, &m.Target, &m.Url, &m.Created, &m.Title, &m.Content, &m.Author, &m.Status)
if err != nil {
return nil, err
}
if m.Url == "" {
m.Url = m.Source
}
if config.submentions {
m.Submentions, err = db.getWebmentions(&webmentionsRequestConfig{
target: m.Source,
submentions: false, // prevent infinite recursion
asc: config.asc,
status: config.status,
})
if err != nil {
return nil, err
}
}
mentions = append(mentions, m)
}
return mentions, nil
}
func (db *database) getWebmentionsByAddress(address string) []*mention {
if address == "" {
return nil
}
mentions, _ := db.getWebmentions(&webmentionsRequestConfig{
target: address,
status: webmentionStatusApproved,
asc: true,
submentions: true,
})
return mentions
}
func (db *database) countWebmentions(config *webmentionsRequestConfig) (count int, err error) {
query, params := buildWebmentionsQuery(config)
query = "select count(*) from (" + query + ")"
row, err := db.queryRow(query, params...)
if err != nil {
return
}
err = row.Scan(&count)
return
}