| """HTTP server base class. |
| |
| Note: the class in this module doesn't implement any HTTP request; see |
| SimpleHTTPServer for simple implementations of GET, HEAD and POST |
| (including CGI scripts). It does, however, optionally implement HTTP/1.1 |
| persistent connections, as of version 0.3. |
| |
| Contents: |
| |
| - BaseHTTPRequestHandler: HTTP request handler base class |
| - test: test function |
| |
| XXX To do: |
| |
| - log requests even later (to capture byte count) |
| - log user-agent header and other interesting goodies |
| - send error log to separate file |
| """ |
| |
| |
| # See also: |
| # |
| # HTTP Working Group T. Berners-Lee |
| # INTERNET-DRAFT R. T. Fielding |
| # <draft-ietf-http-v10-spec-00.txt> H. Frystyk Nielsen |
| # Expires September 8, 1995 March 8, 1995 |
| # |
| # URL: http://www.ics.uci.edu/pub/ietf/http/draft-ietf-http-v10-spec-00.txt |
| # |
| # and |
| # |
| # Network Working Group R. Fielding |
| # Request for Comments: 2616 et al |
| # Obsoletes: 2068 June 1999 |
| # Category: Standards Track |
| # |
| # URL: http://www.faqs.org/rfcs/rfc2616.html |
| |
| # Log files |
| # --------- |
| # |
| # Here's a quote from the NCSA httpd docs about log file format. |
| # |
| # | The logfile format is as follows. Each line consists of: |
| # | |
| # | host rfc931 authuser [DD/Mon/YYYY:hh:mm:ss] "request" ddd bbbb |
| # | |
| # | host: Either the DNS name or the IP number of the remote client |
| # | rfc931: Any information returned by identd for this person, |
| # | - otherwise. |
| # | authuser: If user sent a userid for authentication, the user name, |
| # | - otherwise. |
| # | DD: Day |
| # | Mon: Month (calendar name) |
| # | YYYY: Year |
| # | hh: hour (24-hour format, the machine's timezone) |
| # | mm: minutes |
| # | ss: seconds |
| # | request: The first line of the HTTP request as sent by the client. |
| # | ddd: the status code returned by the server, - if not available. |
| # | bbbb: the total number of bytes sent, |
| # | *not including the HTTP/1.0 header*, - if not available |
| # | |
| # | You can determine the name of the file accessed through request. |
| # |
| # (Actually, the latter is only true if you know the server configuration |
| # at the time the request was made!) |
| |
| __version__ = "0.3" |
| |
| __all__ = ["HTTPServer", "BaseHTTPRequestHandler"] |
| |
| import sys |
| import time |
| import socket # For gethostbyaddr() |
| from warnings import filterwarnings, catch_warnings |
| with catch_warnings(): |
| if sys.py3kwarning: |
| filterwarnings("ignore", ".*mimetools has been removed", |
| DeprecationWarning) |
| import mimetools |
| import SocketServer |
| |
| # Default error message template |
| DEFAULT_ERROR_MESSAGE = """\ |
| <head> |
| <title>Error response</title> |
| </head> |
| <body> |
| <h1>Error response</h1> |
| <p>Error code %(code)d. |
| <p>Message: %(message)s. |
| <p>Error code explanation: %(code)s = %(explain)s. |
| </body> |
| """ |
| |
| DEFAULT_ERROR_CONTENT_TYPE = "text/html" |
| |
| def _quote_html(html): |
| return html.replace("&", "&").replace("<", "<").replace(">", ">") |
| |
| class HTTPServer(SocketServer.TCPServer): |
| |
| allow_reuse_address = 1 # Seems to make sense in testing environment |
| |
| def server_bind(self): |
| """Override server_bind to store the server name.""" |
| SocketServer.TCPServer.server_bind(self) |
| host, port = self.socket.getsockname()[:2] |
| self.server_name = socket.getfqdn(host) |
| self.server_port = port |
| |
| |
| class BaseHTTPRequestHandler(SocketServer.StreamRequestHandler): |
| |
| """HTTP request handler base class. |
| |
| The following explanation of HTTP serves to guide you through the |
| code as well as to expose any misunderstandings I may have about |
| HTTP (so you don't need to read the code to figure out I'm wrong |
| :-). |
| |
| HTTP (HyperText Transfer Protocol) is an extensible protocol on |
| top of a reliable stream transport (e.g. TCP/IP). The protocol |
| recognizes three parts to a request: |
| |
| 1. One line identifying the request type and path |
| 2. An optional set of RFC-822-style headers |
| 3. An optional data part |
| |
| The headers and data are separated by a blank line. |
| |
| The first line of the request has the form |
| |
| <command> <path> <version> |
| |
| where <command> is a (case-sensitive) keyword such as GET or POST, |
| <path> is a string containing path information for the request, |
| and <version> should be the string "HTTP/1.0" or "HTTP/1.1". |
| <path> is encoded using the URL encoding scheme (using %xx to signify |
| the ASCII character with hex code xx). |
| |
| The specification specifies that lines are separated by CRLF but |
| for compatibility with the widest range of clients recommends |
| servers also handle LF. Similarly, whitespace in the request line |
| is treated sensibly (allowing multiple spaces between components |
| and allowing trailing whitespace). |
| |
| Similarly, for output, lines ought to be separated by CRLF pairs |
| but most clients grok LF characters just fine. |
| |
| If the first line of the request has the form |
| |
| <command> <path> |
| |
| (i.e. <version> is left out) then this is assumed to be an HTTP |
| 0.9 request; this form has no optional headers and data part and |
| the reply consists of just the data. |
| |
| The reply form of the HTTP 1.x protocol again has three parts: |
| |
| 1. One line giving the response code |
| 2. An optional set of RFC-822-style headers |
| 3. The data |
| |
| Again, the headers and data are separated by a blank line. |
| |
| The response code line has the form |
| |
| <version> <responsecode> <responsestring> |
| |
| where <version> is the protocol version ("HTTP/1.0" or "HTTP/1.1"), |
| <responsecode> is a 3-digit response code indicating success or |
| failure of the request, and <responsestring> is an optional |
| human-readable string explaining what the response code means. |
| |
| This server parses the request and the headers, and then calls a |
| function specific to the request type (<command>). Specifically, |
| a request SPAM will be handled by a method do_SPAM(). If no |
| such method exists the server sends an error response to the |
| client. If it exists, it is called with no arguments: |
| |
| do_SPAM() |
| |
| Note that the request name is case sensitive (i.e. SPAM and spam |
| are different requests). |
| |
| The various request details are stored in instance variables: |
| |
| - client_address is the client IP address in the form (host, |
| port); |
| |
| - command, path and version are the broken-down request line; |
| |
| - headers is an instance of mimetools.Message (or a derived |
| class) containing the header information; |
| |
| - rfile is a file object open for reading positioned at the |
| start of the optional input data part; |
| |
| - wfile is a file object open for writing. |
| |
| IT IS IMPORTANT TO ADHERE TO THE PROTOCOL FOR WRITING! |
| |
| The first thing to be written must be the response line. Then |
| follow 0 or more header lines, then a blank line, and then the |
| actual data (if any). The meaning of the header lines depends on |
| the command executed by the server; in most cases, when data is |
| returned, there should be at least one header line of the form |
| |
| Content-type: <type>/<subtype> |
| |
| where <type> and <subtype> should be registered MIME types, |
| e.g. "text/html" or "text/plain". |
| |
| """ |
| |
| # The Python system version, truncated to its first component. |
| sys_version = "Python/" + sys.version.split()[0] |
| |
| # The server software version. You may want to override this. |
| # The format is multiple whitespace-separated strings, |
| # where each string is of the form name[/version]. |
| server_version = "BaseHTTP/" + __version__ |
| |
| # The default request version. This only affects responses up until |
| # the point where the request line is parsed, so it mainly decides what |
| # the client gets back when sending a malformed request line. |
| # Most web servers default to HTTP 0.9, i.e. don't send a status line. |
| default_request_version = "HTTP/0.9" |
| |
| def parse_request(self): |
| """Parse a request (internal). |
| |
| The request should be stored in self.raw_requestline; the results |
| are in self.command, self.path, self.request_version and |
| self.headers. |
| |
| Return True for success, False for failure; on failure, an |
| error is sent back. |
| |
| """ |
| self.command = None # set in case of error on the first line |
| self.request_version = version = self.default_request_version |
| self.close_connection = 1 |
| requestline = self.raw_requestline |
| requestline = requestline.rstrip('\r\n') |
| self.requestline = requestline |
| words = requestline.split() |
| if len(words) == 3: |
| command, path, version = words |
| if version[:5] != 'HTTP/': |
| self.send_error(400, "Bad request version (%r)" % version) |
| return False |
| try: |
| base_version_number = version.split('/', 1)[1] |
| version_number = base_version_number.split(".") |
| # RFC 2145 section 3.1 says there can be only one "." and |
| # - major and minor numbers MUST be treated as |
| # separate integers; |
| # - HTTP/2.4 is a lower version than HTTP/2.13, which in |
| # turn is lower than HTTP/12.3; |
| # - Leading zeros MUST be ignored by recipients. |
| if len(version_number) != 2: |
| raise ValueError |
| version_number = int(version_number[0]), int(version_number[1]) |
| except (ValueError, IndexError): |
| self.send_error(400, "Bad request version (%r)" % version) |
| return False |
| if version_number >= (1, 1) and self.protocol_version >= "HTTP/1.1": |
| self.close_connection = 0 |
| if version_number >= (2, 0): |
| self.send_error(505, |
| "Invalid HTTP Version (%s)" % base_version_number) |
| return False |
| elif len(words) == 2: |
| command, path = words |
| self.close_connection = 1 |
| if command != 'GET': |
| self.send_error(400, |
| "Bad HTTP/0.9 request type (%r)" % command) |
| return False |
| elif not words: |
| return False |
| else: |
| self.send_error(400, "Bad request syntax (%r)" % requestline) |
| return False |
| self.command, self.path, self.request_version = command, path, version |
| |
| # Examine the headers and look for a Connection directive |
| self.headers = self.MessageClass(self.rfile, 0) |
| |
| conntype = self.headers.get('Connection', "") |
| if conntype.lower() == 'close': |
| self.close_connection = 1 |
| elif (conntype.lower() == 'keep-alive' and |
| self.protocol_version >= "HTTP/1.1"): |
| self.close_connection = 0 |
| return True |
| |
| def handle_one_request(self): |
| """Handle a single HTTP request. |
| |
| You normally don't need to override this method; see the class |
| __doc__ string for information on how to handle specific HTTP |
| commands such as GET and POST. |
| |
| """ |
| try: |
| self.raw_requestline = self.rfile.readline(65537) |
| if len(self.raw_requestline) > 65536: |
| self.requestline = '' |
| self.request_version = '' |
| self.command = '' |
| self.send_error(414) |
| return |
| if not self.raw_requestline: |
| self.close_connection = 1 |
| return |
| if not self.parse_request(): |
| # An error code has been sent, just exit |
| return |
| mname = 'do_' + self.command |
| if not hasattr(self, mname): |
| self.send_error(501, "Unsupported method (%r)" % self.command) |
| return |
| method = getattr(self, mname) |
| method() |
| self.wfile.flush() #actually send the response if not already done. |
| except socket.timeout, e: |
| #a read or a write timed out. Discard this connection |
| self.log_error("Request timed out: %r", e) |
| self.close_connection = 1 |
| return |
| |
| def handle(self): |
| """Handle multiple requests if necessary.""" |
| self.close_connection = 1 |
| |
| self.handle_one_request() |
| while not self.close_connection: |
| self.handle_one_request() |
| |
| def send_error(self, code, message=None): |
| """Send and log an error reply. |
| |
| Arguments are the error code, and a detailed message. |
| The detailed message defaults to the short entry matching the |
| response code. |
| |
| This sends an error response (so it must be called before any |
| output has been generated), logs the error, and finally sends |
| a piece of HTML explaining the error to the user. |
| |
| """ |
| |
| try: |
| short, long = self.responses[code] |
| except KeyError: |
| short, long = '???', '???' |
| if message is None: |
| message = short |
| explain = long |
| self.log_error("code %d, message %s", code, message) |
| self.send_response(code, message) |
| self.send_header('Connection', 'close') |
| |
| # Message body is omitted for cases described in: |
| # - RFC7230: 3.3. 1xx, 204(No Content), 304(Not Modified) |
| # - RFC7231: 6.3.6. 205(Reset Content) |
| content = None |
| if code >= 200 and code not in (204, 205, 304): |
| # HTML encode to prevent Cross Site Scripting attacks |
| # (see bug #1100201) |
| content = (self.error_message_format % { |
| 'code': code, |
| 'message': _quote_html(message), |
| 'explain': explain |
| }) |
| self.send_header("Content-Type", self.error_content_type) |
| self.end_headers() |
| |
| if self.command != 'HEAD' and content: |
| self.wfile.write(content) |
| |
| error_message_format = DEFAULT_ERROR_MESSAGE |
| error_content_type = DEFAULT_ERROR_CONTENT_TYPE |
| |
| def send_response(self, code, message=None): |
| """Send the response header and log the response code. |
| |
| Also send two standard headers with the server software |
| version and the current date. |
| |
| """ |
| self.log_request(code) |
| if message is None: |
| if code in self.responses: |
| message = self.responses[code][0] |
| else: |
| message = '' |
| if self.request_version != 'HTTP/0.9': |
| self.wfile.write("%s %d %s\r\n" % |
| (self.protocol_version, code, message)) |
| # print (self.protocol_version, code, message) |
| self.send_header('Server', self.version_string()) |
| self.send_header('Date', self.date_time_string()) |
| |
| def send_header(self, keyword, value): |
| """Send a MIME header.""" |
| if self.request_version != 'HTTP/0.9': |
| self.wfile.write("%s: %s\r\n" % (keyword, value)) |
| |
| if keyword.lower() == 'connection': |
| if value.lower() == 'close': |
| self.close_connection = 1 |
| elif value.lower() == 'keep-alive': |
| self.close_connection = 0 |
| |
| def end_headers(self): |
| """Send the blank line ending the MIME headers.""" |
| if self.request_version != 'HTTP/0.9': |
| self.wfile.write("\r\n") |
| |
| def log_request(self, code='-', size='-'): |
| """Log an accepted request. |
| |
| This is called by send_response(). |
| |
| """ |
| |
| self.log_message('"%s" %s %s', |
| self.requestline, str(code), str(size)) |
| |
| def log_error(self, format, *args): |
| """Log an error. |
| |
| This is called when a request cannot be fulfilled. By |
| default it passes the message on to log_message(). |
| |
| Arguments are the same as for log_message(). |
| |
| XXX This should go to the separate error log. |
| |
| """ |
| |
| self.log_message(format, *args) |
| |
| def log_message(self, format, *args): |
| """Log an arbitrary message. |
| |
| This is used by all other logging functions. Override |
| it if you have specific logging wishes. |
| |
| The first argument, FORMAT, is a format string for the |
| message to be logged. If the format string contains |
| any % escapes requiring parameters, they should be |
| specified as subsequent arguments (it's just like |
| printf!). |
| |
| The client ip address and current date/time are prefixed to every |
| message. |
| |
| """ |
| |
| sys.stderr.write("%s - - [%s] %s\n" % |
| (self.client_address[0], |
| self.log_date_time_string(), |
| format%args)) |
| |
| def version_string(self): |
| """Return the server software version string.""" |
| return self.server_version + ' ' + self.sys_version |
| |
| def date_time_string(self, timestamp=None): |
| """Return the current date and time formatted for a message header.""" |
| if timestamp is None: |
| timestamp = time.time() |
| year, month, day, hh, mm, ss, wd, y, z = time.gmtime(timestamp) |
| s = "%s, %02d %3s %4d %02d:%02d:%02d GMT" % ( |
| self.weekdayname[wd], |
| day, self.monthname[month], year, |
| hh, mm, ss) |
| return s |
| |
| def log_date_time_string(self): |
| """Return the current time formatted for logging.""" |
| now = time.time() |
| year, month, day, hh, mm, ss, x, y, z = time.localtime(now) |
| s = "%02d/%3s/%04d %02d:%02d:%02d" % ( |
| day, self.monthname[month], year, hh, mm, ss) |
| return s |
| |
| weekdayname = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'] |
| |
| monthname = [None, |
| 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', |
| 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'] |
| |
| def address_string(self): |
| """Return the client address formatted for logging. |
| |
| This version looks up the full hostname using gethostbyaddr(), |
| and tries to find a name that contains at least one dot. |
| |
| """ |
| |
| host, port = self.client_address[:2] |
| return socket.getfqdn(host) |
| |
| # Essentially static class variables |
| |
| # The version of the HTTP protocol we support. |
| # Set this to HTTP/1.1 to enable automatic keepalive |
| protocol_version = "HTTP/1.0" |
| |
| # The Message-like class used to parse headers |
| MessageClass = mimetools.Message |
| |
| # Table mapping response codes to messages; entries have the |
| # form {code: (shortmessage, longmessage)}. |
| # See RFC 2616. |
| responses = { |
| 100: ('Continue', 'Request received, please continue'), |
| 101: ('Switching Protocols', |
| 'Switching to new protocol; obey Upgrade header'), |
| |
| 200: ('OK', 'Request fulfilled, document follows'), |
| 201: ('Created', 'Document created, URL follows'), |
| 202: ('Accepted', |
| 'Request accepted, processing continues off-line'), |
| 203: ('Non-Authoritative Information', 'Request fulfilled from cache'), |
| 204: ('No Content', 'Request fulfilled, nothing follows'), |
| 205: ('Reset Content', 'Clear input form for further input.'), |
| 206: ('Partial Content', 'Partial content follows.'), |
| |
| 300: ('Multiple Choices', |
| 'Object has several resources -- see URI list'), |
| 301: ('Moved Permanently', 'Object moved permanently -- see URI list'), |
| 302: ('Found', 'Object moved temporarily -- see URI list'), |
| 303: ('See Other', 'Object moved -- see Method and URL list'), |
| 304: ('Not Modified', |
| 'Document has not changed since given time'), |
| 305: ('Use Proxy', |
| 'You must use proxy specified in Location to access this ' |
| 'resource.'), |
| 307: ('Temporary Redirect', |
| 'Object moved temporarily -- see URI list'), |
| |
| 400: ('Bad Request', |
| 'Bad request syntax or unsupported method'), |
| 401: ('Unauthorized', |
| 'No permission -- see authorization schemes'), |
| 402: ('Payment Required', |
| 'No payment -- see charging schemes'), |
| 403: ('Forbidden', |
| 'Request forbidden -- authorization will not help'), |
| 404: ('Not Found', 'Nothing matches the given URI'), |
| 405: ('Method Not Allowed', |
| 'Specified method is invalid for this resource.'), |
| 406: ('Not Acceptable', 'URI not available in preferred format.'), |
| 407: ('Proxy Authentication Required', 'You must authenticate with ' |
| 'this proxy before proceeding.'), |
| 408: ('Request Timeout', 'Request timed out; try again later.'), |
| 409: ('Conflict', 'Request conflict.'), |
| 410: ('Gone', |
| 'URI no longer exists and has been permanently removed.'), |
| 411: ('Length Required', 'Client must specify Content-Length.'), |
| 412: ('Precondition Failed', 'Precondition in headers is false.'), |
| 413: ('Request Entity Too Large', 'Entity is too large.'), |
| 414: ('Request-URI Too Long', 'URI is too long.'), |
| 415: ('Unsupported Media Type', 'Entity body in unsupported format.'), |
| 416: ('Requested Range Not Satisfiable', |
| 'Cannot satisfy request range.'), |
| 417: ('Expectation Failed', |
| 'Expect condition could not be satisfied.'), |
| |
| 500: ('Internal Server Error', 'Server got itself in trouble'), |
| 501: ('Not Implemented', |
| 'Server does not support this operation'), |
| 502: ('Bad Gateway', 'Invalid responses from another server/proxy.'), |
| 503: ('Service Unavailable', |
| 'The server cannot process the request due to a high load'), |
| 504: ('Gateway Timeout', |
| 'The gateway server did not receive a timely response'), |
| 505: ('HTTP Version Not Supported', 'Cannot fulfill request.'), |
| } |
| |
| |
| def test(HandlerClass = BaseHTTPRequestHandler, |
| ServerClass = HTTPServer, protocol="HTTP/1.0"): |
| """Test the HTTP request handler class. |
| |
| This runs an HTTP server on port 8000 (or the first command line |
| argument). |
| |
| """ |
| |
| if sys.argv[1:]: |
| port = int(sys.argv[1]) |
| else: |
| port = 8000 |
| server_address = ('', port) |
| |
| HandlerClass.protocol_version = protocol |
| httpd = ServerClass(server_address, HandlerClass) |
| |
| sa = httpd.socket.getsockname() |
| print "Serving HTTP on", sa[0], "port", sa[1], "..." |
| httpd.serve_forever() |
| |
| |
| if __name__ == '__main__': |
| test() |
