plomlompom.com Git - misc/blob - plomlib.py

   1 import os
   2 from http.server import BaseHTTPRequestHandler
   3 from http.cookies import SimpleCookie
   4 import json
   5
   6
   7 class PlomException(Exception):
   8     pass
   9
  10
  11 class PlomDB:
  12
  13     def __init__(self, db_name):
  14         self.db_file = db_name
  15         self.lock_file = db_name+ '.lock'
  16         if os.path.exists(self.db_file):
  17             with open(self.db_file, 'r') as f:
  18                 self.read_db_file(f)
  19
  20     def lock(self):
  21         if os.path.exists(self.lock_file):
  22             raise PlomException('Sorry, lock file!')
  23         f = open(self.lock_file, 'w+')
  24         f.close()
  25
  26     def unlock(self):
  27         os.remove(self.lock_file)
  28
  29     def backup(self):
  30         import shutil
  31         from datetime import datetime, timedelta
  32         if not os.path.exists(self.db_file):
  33             return
  34
  35         # collect modification times of numbered .bak files
  36         # print('DEBUG BACKUP')
  37         bak_prefix = f'{self.db_file}.bak.'
  38         # backup_dates = []
  39         mtimes_to_paths = {}
  40         for path in [path for path in os.listdir(os.path.dirname(bak_prefix))
  41                      if path.startswith(os.path.basename(bak_prefix))]:
  42             path = os.path.dirname(bak_prefix) + f'/{path}'
  43             mod_time = os.path.getmtime(path)
  44             # print(f'DEBUG pre-exists: {path} {mod_time}')
  45             mtimes_to_paths[str(datetime.fromtimestamp(mod_time))] = path
  46
  47         # for mtime in sorted(mtimes_to_paths.keys()):
  48         #     print(f'DEBUG mtimes_to_paths: {mtime}:{mtimes_to_paths[mtime]}')
  49
  50         # collect what numbered .bak files to save: the older, the fewer; for each
  51         # timedelta, keep the newest file that's older
  52         ages_to_keep = [timedelta(minutes=4**i) for i in range(0, 8)]
  53         # print(f'DEBUG ages_to_keep: {ages_to_keep}')
  54         now = datetime.now()
  55         to_save = {}
  56         for age in ages_to_keep:
  57             limit = now - age
  58             for mtime in reversed(sorted(mtimes_to_paths.keys())):
  59                 # print(f'DEBUG checking if {mtime} < {limit} ({now} - {age})')
  60                 if len(mtime) < 20:
  61                     mtime_test = mtime + '.000000'
  62                 else:
  63                     mtime_test = mtime
  64                 if datetime.strptime(mtime_test, '%Y-%m-%d %H:%M:%S.%f') < limit:
  65                     # print('DEBUG it is, adding!')
  66                     to_save[mtime] = mtimes_to_paths[mtime]
  67                     break
  68
  69         for path in [path for path in mtimes_to_paths.values()
  70                      if path not in to_save.values()]:
  71             # print(f'DEBUG removing {path} cause not in to_save')
  72             os.remove(path)
  73
  74         i = 0
  75         for mtime in sorted(to_save.keys()):
  76             source = to_save[mtime]
  77             target = f'{bak_prefix}{i}'
  78             # print(f'DEBUG to_save {source} -> {target}')
  79             if source != target:
  80                 shutil.move(source, target)
  81             i += 1
  82
  83         # put copy of current state at end of bak list
  84         # print(f'DEBUG saving current state to {bak_prefix}{i}')
  85         shutil.copy(self.db_file, f'{bak_prefix}{i}')
  86
  87     def write_text_to_db(self, text, mode='w'):
  88         self.lock()
  89         self.backup()
  90         with open(self.db_file, mode) as f:
  91             f.write(text);
  92         self.unlock()
  93
  94
  95 class PlomHandler(BaseHTTPRequestHandler):
  96     homepage = '/'
  97     html_head = '<!DOCTYPE html>\n<html>\n<meta charset="UTF-8">'
  98     html_foot = '</body>\n</html>'
  99
 100     def fail_400(self, e):
 101         self.send_HTML(f'ERROR: {e}', 400)
 102
 103     def send_HTML(self, html, code=200):
 104         self.send_code_and_headers(code, [('Content-type', 'text/html')])
 105         self.wfile.write(bytes(f'{self.html_head}\n{html}\n{self.html_foot}', 'utf-8'))
 106
 107     def ensure_cookies_to_set(self):
 108         if not hasattr(self, 'cookies_to_set'):
 109             self.cookies_to_set = []
 110
 111     def set_cookie(self, cookie_name, cookie_path, cookie_db):
 112         self.ensure_cookies_to_set()
 113         cookie = SimpleCookie()
 114         cookie[cookie_name] = json.dumps(cookie_db)
 115         cookie[cookie_name]['path'] = cookie_path
 116         self.cookies_to_set += [cookie]
 117
 118     def unset_cookie(self, cookie_name, cookie_path):
 119         self.ensure_cookies_to_set()
 120         cookie = SimpleCookie()
 121         cookie[cookie_name] = ''
 122         cookie[cookie_name]['path'] = cookie_path
 123         cookie[cookie_name]['expires'] = 'Thu, 01 Jan 1970 00:00:00 GMT'
 124         self.cookies_to_set += [cookie]
 125
 126     def get_cookie_db(self, cookie_name):
 127         cookie_db = {}
 128         if 'Cookie' in self.headers:
 129             cookie = SimpleCookie(self.headers['Cookie'])
 130             if cookie_name in cookie:
 131                 cookie_db = json.loads(cookie[cookie_name].value)
 132         return cookie_db
 133
 134     def send_code_and_headers(self, code, headers=[]):
 135         self.ensure_cookies_to_set()
 136         self.send_response(code)
 137         for cookie in self.cookies_to_set:
 138             for morsel in cookie.values():
 139                 self.send_header('Set-Cookie', morsel.OutputString())
 140         for fieldname, content in headers:
 141             self.send_header(fieldname, content)
 142         self.end_headers()
 143
 144     def redirect(self, url='/'):
 145         self.send_code_and_headers(302, [('Location', url)])
 146
 147     def try_do(self, do_method):
 148         try:
 149             do_method()
 150         except PlomException as e:
 151             self.fail_400(e)
 152
 153
 154
 155 def run_server(port, handler_class):
 156     from http.server import HTTPServer
 157     webServer = HTTPServer(('localhost', port), handler_class)
 158     print(f"Server started http://localhost:{port}")
 159     try:
 160         webServer.serve_forever()
 161     except KeyboardInterrupt:
 162         pass
 163     webServer.server_close()
 164     print("Server stopped.")