writefreely/webfinger.go

146 lines
3.5 KiB
Go

/*
* Copyright © 2018-2021 Musing Studio LLC.
*
* This file is part of WriteFreely.
*
* WriteFreely is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, included
* in the LICENSE file in this source code package.
*/
package writefreely
import (
"encoding/json"
"io"
"net/http"
"strings"
"github.com/writeas/go-webfinger"
"github.com/writeas/impart"
"github.com/writeas/web-core/log"
"github.com/writefreely/writefreely/config"
)
type wfResolver struct {
db *datastore
cfg *config.Config
}
var wfUserNotFoundErr = impart.HTTPError{http.StatusNotFound, "User not found."}
func (wfr wfResolver) FindUser(username string, host, requestHost string, r []webfinger.Rel) (*webfinger.Resource, error) {
var c *Collection
var err error
if username == host {
c = instanceColl
} else if wfr.cfg.App.SingleUser {
c, err = wfr.db.GetCollectionByID(1)
} else {
c, err = wfr.db.GetCollection(username)
}
if err != nil {
log.Error("Unable to get blog: %v", err)
return nil, err
}
c.hostName = wfr.cfg.App.Host
if !c.IsInstanceColl() {
silenced, err := wfr.db.IsUserSilenced(c.OwnerID)
if err != nil {
log.Error("webfinger find user: check is silenced: %v", err)
return nil, err
}
if silenced {
return nil, wfUserNotFoundErr
}
}
if wfr.cfg.App.SingleUser {
// Ensure handle matches user-chosen one on single-user blogs
if username != c.Alias {
log.Info("Username '%s' is not handle '%s'", username, c.Alias)
return nil, wfUserNotFoundErr
}
}
// Only return information if site has federation enabled.
// TODO: enable two levels of federation? Unlisted or Public on timelines?
if !wfr.cfg.App.Federation {
return nil, wfUserNotFoundErr
}
res := webfinger.Resource{
Subject: "acct:" + username + "@" + host,
Aliases: []string{
c.CanonicalURL(),
c.FederatedAccount(),
},
Links: []webfinger.Link{
{
HRef: c.CanonicalURL(),
Type: "text/html",
Rel: "https://webfinger.net/rel/profile-page",
},
{
HRef: c.FederatedAccount(),
Type: "application/activity+json",
Rel: "self",
},
},
}
return &res, nil
}
func (wfr wfResolver) DummyUser(username string, hostname string, r []webfinger.Rel) (*webfinger.Resource, error) {
return nil, wfUserNotFoundErr
}
func (wfr wfResolver) IsNotFoundError(err error) bool {
return err == wfUserNotFoundErr
}
// RemoteLookup looks up a user by handle at a remote server
// and returns the actor URL
func RemoteLookup(handle string) string {
handle = strings.TrimLeft(handle, "@")
// let's take the server part of the handle
parts := strings.Split(handle, "@")
resp, err := http.Get("https://" + parts[1] + "/.well-known/webfinger?resource=acct:" + handle)
if err != nil {
log.Error("Error on webfinger request: %v", err)
return ""
}
body, err := io.ReadAll(resp.Body)
if err != nil {
log.Error("Error on webfinger response: %v", err)
return ""
}
var result webfinger.Resource
err = json.Unmarshal(body, &result)
if err != nil {
log.Error("Unable to parse webfinger response: %v", err)
return ""
}
var href string
// iterate over webfinger links and find the one with
// a self "rel"
for _, link := range result.Links {
if link.Rel == "self" {
href = link.HRef
}
}
// if we didn't find it with the above then
// try using aliases
if href == "" {
// take the last alias because mastodon has the
// https://instance.tld/@user first which
// doesn't work as an href
href = result.Aliases[len(result.Aliases)-1]
}
return href
}