| <!DOCTYPE html> |
| <body> |
| <script> |
| // This document will contain an iframe which will either host echo-policy.py, |
| // or will host another copy of this document, with the nesting level reduced |
| // by one. This way, an arbitrary nesting depth can be achieved, with the |
| // final inner-most frame reporting back the advertised required policy. |
| |
| // The 'id' URL parameter will be passed to the nested document. |
| // The 'level' URL paramater will be reduced by 1 and passed to the nested |
| // document if it was at least 1. (If it was 0, then echo-policy.py will be |
| // nested instead, and the level parameter will not be passed.) |
| |
| // This document is served with a Document Policy header that should satisfy |
| // any requests that include a required policy for the |
| // 'lossless-images-max-bpp' feature. |
| const params = new URLSearchParams(window.location.search); |
| const id = params.get('id'); |
| const level = params.get('level'); |
| |
| const iframe = document.createElement('iframe'); |
| var hostname; |
| if (level >= 1) { |
| params.set('level',level-1); |
| hostname = document.location.pathname + "?" + params.toString(); |
| } else { |
| params.delete('level'); |
| hostname = "/document-policy/echo-policy.py?" + params.toString(); |
| } |
| iframe.src = hostname; |
| document.body.appendChild(iframe); |
| </script> |