GoBlog/activityPubTools.go

82 lines
2.2 KiB
Go

package main
import (
"encoding/json"
"fmt"
"io"
"net/http"
"net/url"
"strings"
"github.com/carlmjohnson/requests"
"github.com/go-chi/chi/v5"
"go.goblog.app/app/pkgs/bodylimit"
)
func (a *goBlog) apRemoteFollow(w http.ResponseWriter, r *http.Request) {
blogName := chi.URLParam(r, "blog")
blog, ok := a.cfg.Blogs[blogName]
if !ok || blog == nil {
a.serveError(w, r, "Blog not found", http.StatusNotFound)
return
}
if user := r.FormValue("user"); user != "" {
// Parse instance
userParts := strings.Split(user, "@")
if len(userParts) < 2 {
a.serveError(w, r, "User must be of the form user@example.org or @user@example.org", http.StatusBadRequest)
return
}
user = userParts[len(userParts)-2]
instance := userParts[len(userParts)-1]
if user == "" || instance == "" {
a.serveError(w, r, "User or instance are empty", http.StatusBadRequest)
return
}
// Get webfinger
type webfingerLinkType struct {
Rel string `json:"rel"`
Template string `json:"template"`
}
type webfingerType struct {
Links []*webfingerLinkType `json:"links"`
}
webfinger := &webfingerType{}
pr, pw := io.Pipe()
go func() {
err := requests.
URL(fmt.Sprintf("https://%s/.well-known/webfinger?resource=acct:%s@%s", instance, user, instance)).
Client(a.httpClient).
ToWriter(pw).
Fetch(r.Context())
_ = pw.CloseWithError(err)
}()
err := json.NewDecoder(io.LimitReader(pr, 100*bodylimit.KB)).Decode(webfinger)
_ = pr.CloseWithError(err)
if err != nil {
a.serveError(w, r, "Failed to query webfinger", http.StatusInternalServerError)
return
}
// Check webfinger and find template
template := ""
for _, link := range webfinger.Links {
if link.Rel == "http://ostatus.org/schema/1.0/subscribe" {
template = link.Template
break
}
}
if template == "" {
a.serveError(w, r, "Instance does not support subscribe schema version 1.0", http.StatusInternalServerError)
return
}
// Build redirect
redirect := strings.ReplaceAll(template, "{uri}", url.PathEscape(a.apIri(blog)))
http.Redirect(w, r, redirect, http.StatusFound)
return
}
// Render remote follow form
a.render(w, r, a.renderActivityPubRemoteFollow, &renderData{
BlogString: blogName,
})
}