GoBlog/webmentionVerification.go

189 lines
4.7 KiB
Go

package main
import (
"bytes"
"database/sql"
"errors"
"fmt"
"io"
"log"
"net/http"
"net/url"
"os"
"github.com/PuerkitoBio/goquery"
"github.com/joncrlsn/dque"
"willnorris.com/go/microformats"
)
var wmQueue *dque.DQue
func wmMentionBuilder() interface{} {
return &mention{}
}
func initWebmentionQueue() (err error) {
queuePath := "queues"
if _, err := os.Stat(queuePath); os.IsNotExist(err) {
if err := os.Mkdir(queuePath, 0755); err != nil {
return err
}
} else if err != nil {
return err
}
wmQueue, err = dque.NewOrOpen("webmention", queuePath, 5, wmMentionBuilder)
if err != nil {
return err
}
startWebmentionQueue()
return nil
}
func startWebmentionQueue() {
go func() {
for {
if i, err := wmQueue.PeekBlock(); err == nil {
if i == nil {
// Empty request
_, _ = wmQueue.Dequeue()
continue
}
if m, ok := i.(*mention); ok {
err = m.verifyMention()
if err != nil {
log.Println(fmt.Sprintf("Failed to verify webmention from %s to %s: %s", m.Source, m.Target, err.Error()))
}
_, _ = wmQueue.Dequeue()
} else {
// Invalid type
_, _ = wmQueue.Dequeue()
}
}
}
}()
}
func queueMention(m *mention) error {
return wmQueue.Enqueue(m)
}
func (m *mention) verifyMention() error {
req, err := http.NewRequest(http.MethodGet, m.Source, nil)
if err != nil {
return err
}
req.Header.Set(userAgent, appUserAgent)
resp, err := http.DefaultClient.Do(req)
if err != nil {
return err
}
err = m.verifyReader(resp.Body)
_ = resp.Body.Close()
if err != nil {
_, err := appDbExec("delete from webmentions where source = @source and target = @target", sql.Named("source", m.Source), sql.Named("target", m.Target))
return err
}
if len(m.Content) > 500 {
m.Content = m.Content[0:497] + "…"
}
if len(m.Title) > 60 {
m.Title = m.Title[0:57] + "…"
}
newStatus := webmentionStatusVerified
if webmentionExists(m.Source, m.Target) {
_, err = appDbExec("update webmentions set status = @status, title = @title, content = @content, author = @author where source = @source and target = @target",
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("target", m.Target))
} else {
_, err = appDbExec("insert into webmentions (source, target, created, status, title, content, author) values (@source, @target, @created, @status, @title, @content, @author)",
sql.Named("source", m.Source), sql.Named("target", m.Target), sql.Named("created", m.Created), sql.Named("status", newStatus), sql.Named("title", m.Title), sql.Named("content", m.Content), sql.Named("author", m.Author))
sendNotification(fmt.Sprintf("New webmention from %s to %s", m.Source, m.Target))
}
return err
}
func (m *mention) verifyReader(body io.Reader) error {
var linksBuffer, gqBuffer, mfBuffer bytes.Buffer
if _, err := io.Copy(io.MultiWriter(&linksBuffer, &gqBuffer, &mfBuffer), body); err != nil {
return err
}
// Check if source mentions target
links, err := allLinksFromHTML(&linksBuffer, m.Source)
if err != nil {
return err
}
hasLink := false
for _, link := range links {
if unescapedPath(link) == unescapedPath(m.Target) {
hasLink = true
break
}
}
if !hasLink {
return errors.New("target not found in source")
}
// Set title
doc, err := goquery.NewDocumentFromReader(&gqBuffer)
if err != nil {
return err
}
if title := doc.Find("title"); title != nil {
m.Title = title.Text()
}
// Fill mention attributes
sourceURL, err := url.Parse(m.Source)
if err != nil {
return err
}
m.fillFromData(microformats.Parse(&mfBuffer, sourceURL))
return nil
}
func (m *mention) fillFromData(mf *microformats.Data) {
for _, i := range mf.Items {
m.fill(i)
}
}
func (m *mention) fill(mf *microformats.Microformat) bool {
if mfHasType(mf, "h-entry") {
if name, ok := mf.Properties["name"]; ok && len(name) > 0 {
if title, ok := name[0].(string); ok {
m.Title = title
}
}
if contents, ok := mf.Properties["content"]; ok && len(contents) > 0 {
if content, ok := contents[0].(map[string]string); ok {
if contentValue, ok := content["value"]; ok {
m.Content = contentValue
}
}
}
if authors, ok := mf.Properties["author"]; ok && len(authors) > 0 {
if author, ok := authors[0].(*microformats.Microformat); ok {
if names, ok := author.Properties["name"]; ok && len(names) > 0 {
if name, ok := names[0].(string); ok {
m.Author = name
}
}
}
}
return true
} else if len(mf.Children) > 0 {
for _, mfc := range mf.Children {
if m.fill(mfc) {
return true
}
}
}
return false
}
func mfHasType(mf *microformats.Microformat, typ string) bool {
for _, t := range mf.Type {
if typ == t {
return true
}
}
return false
}