gotosocial/internal/transport/derefdomainpermlist.go
2024-12-24 18:05:20 +01:00

124 lines
3.7 KiB
Go

// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package transport
import (
"context"
"io"
"net/http"
"github.com/superseriousbusiness/gotosocial/internal/gtserror"
"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
)
type DereferenceDomainPermissionsResp struct {
// Set only if response was 200 OK.
// It's up to the caller to close
// this when they're done with it.
Body io.ReadCloser
// True if response
// was 304 Not Modified.
Unmodified bool
// May be set
// if 200 or 304.
ETag string
}
func (t *transport) DereferenceDomainPermissions(
ctx context.Context,
permSub *gtsmodel.DomainPermissionSubscription,
force bool,
) (*DereferenceDomainPermissionsResp, error) {
// Prepare new HTTP request to endpoint
req, err := http.NewRequestWithContext(ctx, "GET", permSub.URI, nil)
if err != nil {
return nil, err
}
// Set basic auth header if necessary.
if permSub.FetchUsername != "" || permSub.FetchPassword != "" {
req.SetBasicAuth(permSub.FetchUsername, permSub.FetchPassword)
}
// Set relevant Accept headers.
// Allow fallback in case target doesn't
// negotiate content type correctly.
req.Header.Add("Accept-Charset", "utf-8")
req.Header.Add("Accept", permSub.ContentType.String()+","+"*/*")
// If force is true, we want to skip setting Cache
// headers so that we definitely don't get a 304 back.
if !force {
// If we've successfully fetched this list
// before, set If-Modified-Since to last
// success to make the request conditional.
//
// See: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/If-Modified-Since
if !permSub.SuccessfullyFetchedAt.IsZero() {
timeStr := permSub.SuccessfullyFetchedAt.Format(http.TimeFormat)
req.Header.Add("If-Modified-Since", timeStr)
}
// If we've got an ETag stored for this list, set
// If-None-Match to make the request conditional.
// See https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/ETag#caching_of_unchanged_resources.
if len(permSub.ETag) != 0 {
req.Header.Add("If-None-Match", permSub.ETag)
}
}
// Perform the HTTP request
rsp, err := t.GET(req)
if err != nil {
return nil, err
}
// If we have an unexpected / error response,
// wrap + return as error. This will also drain
// and close the response body for us.
if rsp.StatusCode != http.StatusOK &&
rsp.StatusCode != http.StatusNotModified {
err := gtserror.NewFromResponse(rsp)
return nil, err
}
// Check already if we were given an ETag
// we can use, as ETag is often returned
// even on 304 Not Modified responses.
eTag := rsp.Header.Get("ETag")
if rsp.StatusCode == http.StatusNotModified {
// Nothing has changed on the remote side
// since we last fetched, so there's nothing
// to do and we don't need to read the body.
rsp.Body.Close()
return &DereferenceDomainPermissionsResp{
Unmodified: true,
ETag: eTag,
}, nil
}
// Return the body + ETag to the caller.
return &DereferenceDomainPermissionsResp{
Body: rsp.Body,
ETag: eTag,
}, nil
}