| package plugin |
| |
| /* |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| import ( |
| "net/http" |
| |
| "github.com/apache/trafficcontrol/lib/go-rfc" |
| ) |
| |
| func init() { |
| AddPlugin(5000, Funcs{beforeRespond: ifModifiedSince}) |
| } |
| |
| func ifModifiedSince(icfg interface{}, d BeforeRespondData) { |
| if d.CacheObj == nil { |
| return // if we don't have a cacheobj from the origin, there's no object to have been modified. |
| } |
| modifiedSince, ok := rfc.GetHTTPDate(d.Req.Header, "If-Modified-Since") |
| if !ok { |
| return |
| } |
| if d.CacheObj.LastModified.After(modifiedSince) { |
| return |
| } |
| *d.Code, *d.Hdr, *d.Body = http.StatusNotModified, nil, nil |
| } |