なんだこれ……。「限定共有投稿」に黒魔術が残っていたので晒す。

# -*- coding:utf-8 -*-
import BaseHTTPServer
import json

class MyHandler(BaseHTTPServer.BaseHTTPRequestHandler):
 
	def do_GET(self):
		if self.path.endswith('favicon.ico'):
			return
		
		self.send_response(200)
		self.end_headers()
		self.wfile.write(index_handler());
		return

	def do_POST(self):
		self.send_response(200)
		content_len = int(self.headers.get('content-length'))
		requestBody = json.loads(self.rfile.read(content_len))
		if self.path.endswith('my.pdf'):
			self.send_header("content-type", "application/pdf")
			self.end_headers()
			self.wfile.write(lambda_handler(requestBody, {}))
		return

def lambda_handler(data, context):
	return """%%PDF-1.4
1 0 obj
<</Pages 2 0 R/Type /Catalog>>
endobj
2 0 obj
<</Kids [3 0 R]/Count 1/Type/Pages>>
endobj
3 0 obj
<</Contents 5 0 R/Parent 2 0 R/MediaBox[0 0 612 292]/Resources<</Font<</F1 4 0 R >>/ProcSet[/PDF/Text]>>/Type/Page>>
endobj
4 0 obj
<</Type/Font/Subtype/Type1/Name/F1/BaseFont/Helvetica/Encoding/MacRomanEncoding>>
endobj
5 0 obj
<</Length 73 >> stream
BT /F1 24 Tf 30 100 Td (%s) Tj ET
endstream
endobj
xref
0 7
0000000000 65535 f
0000000010 00000 n
0000000059 00000 n
0000000114 00000 n
0000000249 00000 n
0000000349 00000 n
trailer << /Size 7 /Root 1 0 R >>
startxref
%d
%%%%EOF""" % (data['message'], 433+len(data['message']))

def index_handler():
	return """<!DOCTYPE html>
<html>
<head>
  <title>a</title>
  <style>
	div, embed { width: 100%; height: 125vw; }
  </style>
</head>
<body>
  <button id="b1">view pdf</button>
  <div id="d1"></div>
  <script>
  (function() {
	document.getElementById("b1").addEventListener("click", function() {
	  // ブロックされないようにclickハンドラ内でオープンしとく
	  var previewWindow = window.open("", "preview");
	  var xhr = new XMLHttpRequest();
	  xhr.onreadystatechange = function() {
		if(xhr.readyState === 4 && xhr.status === 200){
		  var url = URL.createObjectURL(this.response);
		  if(window.navigator.msSaveOrOpenBlob) {
		    window.navigator.msSaveOrOpenBlob(this.response, 'my.pdf');
		  } else {
		    // オープンしといた別Windowで表示
		    previewWindow.location.href = url;
		    // 埋め込んじゃうというのも
		    document.getElementById("d1").innerHTML = 
		      '<embed type="application/pdf" src="' + url + '"></embed>';
		  }
		}
	  };
	  // JSON形式でポストして結果はblobで受け取る
	  window.setTimeout(function() {
		xhr.open("POST", "my.pdf");
		xhr.responseType = "blob";
		xhr.setRequestHeader('Content-Type', 'application/json');
		xhr.send('{"message":"Hello!!"}');
	  }, 1000);
	});
  })();
  </script>
</body>
</html>"""

if __name__ == '__main__':
	server_address = ('', 8080)
	httpd = BaseHTTPServer.HTTPServer(server_address, MyHandler)
	httpd.serve_forever()