diff options
Diffstat (limited to 'internal/transport/derefdomainpermlist.go')
-rw-r--r-- | internal/transport/derefdomainpermlist.go | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/internal/transport/derefdomainpermlist.go b/internal/transport/derefdomainpermlist.go new file mode 100644 index 000000000..c81117bc6 --- /dev/null +++ b/internal/transport/derefdomainpermlist.go @@ -0,0 +1,121 @@ +// 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, + skipCache 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 skipCache is true, we want to skip setting Cache + // headers so that we definitely don't get a 304 back. + if !skipCache { + // 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. + permsResp := &DereferenceDomainPermissionsResp{ + 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() + permsResp.Unmodified = true + } else { + // Return the live body to the caller. + permsResp.Body = rsp.Body + } + + return permsResp, nil +} |