update README, add CGI

pirms 4 nedēļām · ca5f408077
--- a/+ 6
+++ b/+ 6
@@ -1,9 +1,14 @@
 PYTHON=python3

 ALLFILES=templates/S2_perm_sw.html templates/S4_server.py venv static/i-ico.png static/i-banner.png

 .PHONY: run
 run: templates/S2_perm_sw.html templates/S4_server.py venv static/i-ico.png static/i-banner.png
 run: $(ALLFILES)
 	($(VENVACT) && python templates/S4_server.py $(PORT) )

 .PHONY: files
 files: $(ALLFILES)

 VENVACT=. ./venv/bin/activate

 venv:
--- a/README.md
+++ b/README.md
@@ -1,29 +1,123 @@
 Web Push Notifications (WPN)
 ===========================

 This is designed to be a super simple and small tool to push
 notifications to your end points.
 This is designed to be a super simple (understandable) and small tool
 to push notifications to web browsers (e.g. your cell phone).

 This code is partly copied from:
 https://gist.github.com/code-boxx/bc6aed37345ad1783cfb7d230f438120

 But put into a repo w/ better install instructions, and turned into a
 usable bit of code.

 The web browser Push API is fully encrypted and authenticated.  This
 means that only your server and the client will be able to see the
 contents of the message.

 There is also a limit of 4k for the entire message that is composed
 and sent to the server.  This means that the usable space for your
 own contents is around 3k, which is more than enough.


 Installation and Setup
 ----------------------

 There are two ways to install it, one is to use it via the Flask web
 server, or via a CGI.

 ### Flask web server

 Installation/running:
 ```
 git clonse <url>
 git clone https://www.funkthat.com/gitea/jmg/wpn
 cd wpn
 make run EMAIL=myemail@example.com PORT=<someport>
 ```

 This code is partly copied from:
 https://gist.github.com/code-boxx/bc6aed37345ad1783cfb7d230f438120
 Then you go to `http://127.0.0.1:<someport>/`, click the `Request
 Notifications` button.  The sub info will be printed to the console,
 and a second later, a notification should appear, and it'll be repeated
 every 10 seconds.  To change this behavior, look at the `donotify`
 fucntion in `src/S4_server.py`.

 But put into a repo w/ better install instructions, and turned into a
 usable bit of code.

 ### CGI

 First build the files needed:
 ```
 git clone https://www.funkthat.com/gitea/jmg/wpn
 cd wpn
 make files EMAIL=myemail@example.com
 ```

 Then copy the files in the directory `static`, the files
 `template/S2_perm_sw.html` and `push.py` to a directory on your
 webserver.  In that directory, set push.py executable
 (`chmod 755 push.py`), and create a symlink to it from `push`:
 `ln -s push.py push`.

 Configure your web server such that the `push` is a CGI, and that
 `S2_perm_sw.html` is the index file.  This is how to do it via Apache:
 ```
 <Directory "/location/on/webserver">
  Options +ExecCGI
  Order allow,deny
  Allow from all
  DirectoryIndex S2_perm_sw.html
  <FilesMatch "push$">
      SetHandler cgi-script
  </FilesMatch>
 </Directory>
 ```

 The `push.py` file is used to get the push notification subscription
 information from the browser and put it in `/tmp/subinfo.txt`.

 Note: The `push.py` has a hand implemented version of form decoding
 because Python had deprecated the `cgi` module.

 Pushing Notifications
 ---------------------

 Using the subscription information from the previous step, put it
 in a file for use as `<filewsubjson>` below.

 The `pywebpush` program that is installed by the `pywebpush` module
 is used to send notifications:
 ```
 jq --arg email myemail@example.com -n '{ "sub": ("mailto:" + $email) }' > claim.txt
 jq --arg msg 'somemessage' --arg title notification -n '{ "title": $title, "body": $msg, "icon" : "static/i-ico.png", "image" : "static/i-banner.png" }' |
 pywebpush --data /dev/stdin --info <filewsubjson> --key keys/private_key.pem --claims claim.txt
 ```

 As Python's `[venv](https://docs.python.org/3/library/venv.html#module-venv)`
 is used, you can simply execute/link to the pywebpush program in `venv/bin/`
 and not have to source the environment each time you need to run the program.

 Compatibility
 -------------

 Currently Firefox for Android does not allow Push notifications.  The
 nightly version does allow it.


 ### cryptography

 If you have troubles installing the `cryptography` dependency (due to
 rust or other compile issues), but can install `pycryptodome`, you can
 use the [pycryptowrap](https://www.funkthat.com/gitea/jmg/pycryptowrap)
 instead.  To use it:
 ```
 python3 -m venv venv
 (. ./venv/bin/activate && pip install git+https://www.funkthat.com/gitea/jmg/pycryptowrap )
 (. ./venv/bin/activate && pip install flask ecdsa pywebpush )
 ```

 Notes
 =====
 -----

 If put behind a reverse proxy, make sure the url contains a trailing
 slash.  If you want the path w/o the slash to work, add a redirect as
 well.
 well.  Though if you use the CGI version, this is likely unneeded.

 For Apache:
 ```
@@ -32,5 +126,11 @@ LoadModule proxy_http_module libexec/apache22/mod_proxy_http.so

 ProxyPass "/wpn/" "http://internalwpn.example.com/"
 ProxyPassReverse "/wpn/" "http://internalwpn.example.com/"
 Redirect permanent /spn https://www.example.com/wpn/
 Redirect permanent /wpn https://www.example.com/wpn/
 ```

 See the introduction section on message limits.

 Yes, I probably should have used a better template language than `sed`,
 but this is simple and works.  It also makes it easy to copy over to a
 static site more easily.
--- a/push.py
+++ b/push.py
@@ -0,0 +1,146 @@
 #!/usr/local/bin/python3

 import email.mime.multipart
 import os
 import sys
 import traceback
 import unittest

 from email.message import Message
 from urllib.parse import parse_qs

 def _deb(*args):
 	if True:
 		print(*args, file=sys.stderr)
 	
 def getdata(ct, bstr):
 	_deb('ct:', repr(ct))
 	_deb('bstr:', repr(bstr))
 	m = Message()
 	m['content-type'] = ct
 	boundary = '--' + m.get_param('boundary')

 	# trim the end:
 	_deb('bstr:', repr(bstr))

 	# pretend we had the previous record
 	body = b'\r\n' + bstr.split(('\r\n' + boundary + '--\r\n').encode('ASCII'), 1)[0]

 	_deb('body:', repr(body))

 	parts = body.split(('\r\n' + boundary + '\r\n').encode('ASCII'))[1:]

 	msgs = [ x for x in map(email.message_from_bytes, parts) if x.get_param('name', header='content-disposition') == 'sub' ]

 	return msgs[0].get_payload()

 if __name__ == '__main__':
 	_deb('env:', repr(os.environ))
 	contentlen = int(os.environ.get('CONTENT_LENGTH', '0'))

 	body = sys.stdin.buffer.read(contentlen)

 	try:
 		sub = getdata(os.environ.get('CONTENT_TYPE'), body)

 		os.umask(0o66)
 		with open('/tmp/subinfo.txt', 'w') as fp:
 			print(sub, file=fp)

 		print('Content-Type: text/plain\r')
 		print('\r')
 		print('OK\r')
 	except:
 		_deb(traceback.format_exc())

 		print('status: 500 Server Error\r')
 		print('Content-Type: text/plain\r')
 		print('\r')
 		print('ERROR\r')

 class Test(unittest.TestCase):
 	_testdata = '''
 	0x0040:       504f 5354 202f 7075 7368 2048 5454  ..POST./push.HTT
 	0x0050:  502f 312e 310d 0a48 6f73 743a 2031 3932  P/1.1..Host:.192
 	0x0060:  2e31 3638 2e30 2e33 0d0a 5573 6572 2d41  .168.0.3..User-A
 	0x0070:  6765 6e74 3a20 4d6f 7a69 6c6c 612f 352e  gent:.Mozilla/5.
 	0x0080:  3020 284d 6163 696e 746f 7368 3b20 496e  0.(Macintosh;.In
 	0x0090:  7465 6c20 4d61 6320 4f53 2058 2031 302e  tel.Mac.OS.X.10.
 	0x00a0:  3135 3b20 7276 3a31 3039 2e30 2920 4765  15;.rv:109.0).Ge
 	0x00b0:  636b 6f2f 3230 3130 3031 3031 2046 6972  cko/20100101.Fir
 	0x00c0:  6566 6f78 2f31 3135 2e30 0d0a 4163 6365  efox/115.0..Acce
 	0x00d0:  7074 3a20 2a2f 2a0d 0a41 6363 6570 742d  pt:.*/*..Accept-
 	0x00e0:  4c61 6e67 7561 6765 3a20 656e 2d55 532c  Language:.en-US,
 	0x00f0:  656e 3b71 3d30 2e35 0d0a 4163 6365 7074  en;q=0.5..Accept
 	0x0100:  2d45 6e63 6f64 696e 673a 2067 7a69 702c  -Encoding:.gzip,
 	0x0110:  2064 6566 6c61 7465 2c20 6272 0d0a 5265  .deflate,.br..Re
 	0x0120:  6665 7265 723a 2068 7474 7073 3a2f 2f77  ferer:.https://w
 	0x0130:  7777 2e66 756e 6b74 6861 742e 636f 6d2f  ww.funkthat.com/
 	0x0140:  7765 6270 7573 682f 0d0a 436f 6e74 656e  webpush/..Conten
 	0x0150:  742d 5479 7065 3a20 6d75 6c74 6970 6172  t-Type:.multipar
 	0x0160:  742f 666f 726d 2d64 6174 613b 2062 6f75  t/form-data;.bou
 	0x0170:  6e64 6172 793d 2d2d 2d2d 2d2d 2d2d 2d2d  ndary=----------
 	0x0180:  2d2d 2d2d 2d2d 2d2d 2d2d 2d2d 2d2d 2d2d  ----------------
 	0x0190:  2d33 3435 3837 3235 3136 3133 3033 3132  -345872516130312
 	0x01a0:  3635 3935 3233 3135 3033 3739 3130 310d  659523150379101.
 	0x01b0:  0a4f 7269 6769 6e3a 2068 7474 7073 3a2f  .Origin:.https:/
 	0x01c0:  2f77 7777 2e66 756e 6b74 6861 742e 636f  /www.funkthat.co
 	0x01d0:  6d0d 0a44 4e54 3a20 310d 0a53 6563 2d46  m..DNT:.1..Sec-F
 	0x01e0:  6574 6368 2d44 6573 743a 2065 6d70 7479  etch-Dest:.empty
 	0x01f0:  0d0a 5365 632d 4665 7463 682d 4d6f 6465  ..Sec-Fetch-Mode
 	0x0200:  3a20 636f 7273 0d0a 5365 632d 4665 7463  :.cors..Sec-Fetc
 	0x0210:  682d 5369 7465 3a20 7361 6d65 2d6f 7269  h-Site:.same-ori
 	0x0220:  6769 6e0d 0a53 6563 2d47 5043 3a20 310d  gin..Sec-GPC:.1.
 	0x0230:  0a58 2d46 6f72 7761 7264 6564 2d46 6f72  .X-Forwarded-For
 	0x0240:  3a20 3139 322e 3136 382e 302e 330d 0a58  :.192.168.0.3..X
 	0x0250:  2d46 6f72 7761 7264 6564 2d48 6f73 743a  -Forwarded-Host:
 	0x0260:  2077 7777 2e66 756e 6b74 6861 742e 636f  .www.funkthat.co
 	0x0270:  6d0d 0a58 2d46 6f72 7761 7264 6564 2d53  m..X-Forwarded-S
 	0x0280:  6572 7665 723a 2077 7777 2e66 756e 6b74  erver:.www.funkt
 	0x0290:  6861 742e 636f 6d0d 0a43 6f6e 6e65 6374  hat.com..Connect
 	0x02a0:  696f 6e3a 204b 6565 702d 416c 6976 650d  ion:.Keep-Alive.
 	0x02b0:  0a43 6f6e 7465 6e74 2d4c 656e 6774 683a  .Content-Length:
 	0x02c0:  2035 3833 0d0a 0d0a 2d2d 2d2d 2d2d 2d2d  .583....--------
 	0x02d0:  2d2d 2d2d 2d2d 2d2d 2d2d 2d2d 2d2d 2d2d  ----------------
 	0x02e0:  2d2d 2d2d 2d33 3435 3837 3235 3136 3133  -----34587251613
 	0x02f0:  3033 3132 3635 3935 3233 3135 3033 3739  0312659523150379
 	0x0300:  3130 310d 0a43 6f6e 7465 6e74 2d44 6973  101..Content-Dis
 	0x0310:  706f 7369 7469 6f6e 3a20 666f 726d 2d64  position:.form-d
 	0x0320:  6174 613b 206e 616d 653d 2273 7562 220d  ata;.name="sub".
 	0x0330:  0a0d 0a7b 2265 6e64 706f 696e 7422 3a22  ...{"endpoint":"
 	0x0340:  6874 7470 733a 2f2f 7570 6461 7465 732e  https://updates.
 	0x0350:  7075 7368 2e73 6572 7669 6365 732e 6d6f  push.services.mo
 	0x0360:  7a69 6c6c 612e 636f 6d2f 7770 7573 682f  zilla.com/wpush/
 	0x04c0:  5a4e 565a 6441 535f 4954 3822 7d7d 0d0a  ZNVZdAS_IT8"}}..
 	0x04d0:  2d2d 2d2d 2d2d 2d2d 2d2d 2d2d 2d2d 2d2d  ----------------
 	0x04e0:  2d2d 2d2d 2d2d 2d2d 2d2d 2d2d 2d33 3435  -------------345
 	0x04f0:  3837 3235 3136 3133 3033 3132 3635 3935  8725161303126595
 	0x0500:  3233 3135 3033 3739 3130 312d 2d0d 0a    23150379101--..
 '''

 	@staticmethod
 	def _process_hexdump(data):
 		lines = (x.split(':', 1)[1].strip().split('  ', 1)[0] for x in data.split('\n') if x.strip())

 		return bytes.fromhex(''.join(lines))

 	def test_basic(self):
 		bstr = self._process_hexdump(self._testdata)

 		# drop post line
 		bstr = bstr.split(b'\r\n', 1)[1]

 		_deb(repr(bstr))
 		msg = email.message_from_bytes(bstr)
 		_deb('msg hdrs:', repr(msg.items()))

 		# get ct
 		ct = msg['content-type']
 		_deb('ct:', repr(ct))

 		# get body:
 		body = bstr.split(b'\r\n\r\n', 1)[1]

 		# do the actual test:
 		res = getdata(ct, body)
 		self.assertEqual(res, '{"endpoint":"https://updates.push.services.mozilla.com/wpush/ZNVZdAS_IT8"}}')