BaseHTTPServer — Basic HTTP server
Note
The BaseHTTPServer module has been merged into http.server in
Python 3.0. The 2to3 tool will automatically adapt imports when
converting your sources to 3.0.
This module defines two classes for implementing HTTP servers (Web servers).
Usually, this module isn’t used directly, but is used as a basis for building
functioning Web servers. See the SimpleHTTPServer and
CGIHTTPServer modules.
The first class, HTTPServer, is a SocketServer.TCPServer
subclass. It creates and listens at the HTTP socket, dispatching the requests
to a handler. Code to create and run the server looks like this:
def run(server_class=BaseHTTPServer.HTTPServer,
handler_class=BaseHTTPServer.BaseHTTPRequestHandler):
server_address = ('', 8000)
httpd = server_class(server_address, handler_class)
httpd.serve_forever()
-
class BaseHTTPServer.HTTPServer(server_address, RequestHandlerClass)
- This class builds on the TCPServer class by storing the server
address as instance variables named server_name and
server_port. The server is accessible by the handler, typically
through the handler’s server instance variable.
-
class BaseHTTPServer.BaseHTTPRequestHandler(request, client_address, server)
This class is used to handle the HTTP requests that arrive at the server. By
itself, it cannot respond to any actual HTTP requests; it must be subclassed
to handle each request method (e.g. GET or
POST). BaseHTTPRequestHandler provides a number of class and
instance variables, and methods for use by subclasses.
The handler will parse the request and the headers, then call a method
specific to the request type. The method name is constructed from the
request. For example, for the request method SPAM, the do_SPAM()
method will be called with no arguments. All of the relevant information is
stored in instance variables of the handler. Subclasses should not need to
override or extend the __init__() method.
BaseHTTPRequestHandler has the following instance variables:
-
client_address
- Contains a tuple of the form (host, port) referring to the client’s
address.
-
server
- Contains the server instance.
-
command
- Contains the command (request type). For example, 'GET'.
-
path
- Contains the request path.
-
request_version
- Contains the version string from the request. For example, 'HTTP/1.0'.
-
headers
- Holds an instance of the class specified by the MessageClass class
variable. This instance parses and manages the headers in the HTTP
request.
-
rfile
- Contains an input stream, positioned at the start of the optional input
data.
-
wfile
- Contains the output stream for writing a response back to the
client. Proper adherence to the HTTP protocol must be used when writing to
this stream.
BaseHTTPRequestHandler has the following class variables:
-
server_version
- Specifies 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]. For example, 'BaseHTTP/0.2'.
-
sys_version
- Contains the Python system version, in a form usable by the
version_string method and the server_version class
variable. For example, 'Python/1.4'.
-
error_message_format
- Specifies a format string for building an error response to the client. It
uses parenthesized, keyed format specifiers, so the format operand must be
a dictionary. The code key should be an integer, specifying the numeric
HTTP error code value. message should be a string containing a
(detailed) error message of what occurred, and explain should be an
explanation of the error code number. Default message and explain
values can found in the responses class variable.
-
error_content_type
Specifies the Content-Type HTTP header of error responses sent to the
client. The default value is 'text/html'.
New in version 2.6: Previously, the content type was always 'text/html'.
-
protocol_version
- This specifies the HTTP protocol version used in responses. If set to
'HTTP/1.1', the server will permit HTTP persistent connections;
however, your server must then include an accurate Content-Length
header (using send_header()) in all of its responses to clients.
For backwards compatibility, the setting defaults to 'HTTP/1.0'.
-
MessageClass
Specifies a rfc822.Message-like class to parse HTTP headers.
Typically, this is not overridden, and it defaults to
mimetools.Message.
-
responses
- This variable contains a mapping of error code integers to two-element tuples
containing a short and long message. For example, {code: (shortmessage,
longmessage)}. The shortmessage is usually used as the message key in an
error response, and longmessage as the explain key (see the
error_message_format class variable).
A BaseHTTPRequestHandler instance has the following methods:
-
handle()
- Calls handle_one_request() once (or, if persistent connections are
enabled, multiple times) to handle incoming HTTP requests. You should
never need to override it; instead, implement appropriate do_*()
methods.
-
handle_one_request()
- This method will parse and dispatch the request to the appropriate
do_*() method. You should never need to override it.
-
send_error(code[, message])
- Sends and logs a complete error reply to the client. The numeric code
specifies the HTTP error code, with message as optional, more specific text. A
complete set of headers is sent, followed by text composed using the
error_message_format class variable.
-
send_response(code[, message])
- Sends a response header and logs the accepted request. The HTTP response
line is sent, followed by Server and Date headers. The values for
these two headers are picked up from the version_string() and
date_time_string() methods, respectively.
-
send_header(keyword, value)
- Writes a specific HTTP header to the output stream. keyword should
specify the header keyword, with value specifying its value.
-
end_headers()
- Sends a blank line, indicating the end of the HTTP headers in the
response.
-
log_request([code[, size]])
- Logs an accepted (successful) request. code should specify the numeric
HTTP code associated with the response. If a size of the response is
available, then it should be passed as the size parameter.
-
log_error(...)
- Logs an error when a request cannot be fulfilled. By default, it passes
the message to log_message(), so it takes the same arguments
(format and additional values).
-
log_message(format, ...)
- Logs an arbitrary message to sys.stderr. This is typically overridden
to create custom error logging mechanisms. The format argument is a
standard printf-style format string, where the additional arguments to
log_message() are applied as inputs to the formatting. The client
address and current date and time are prefixed to every message logged.
-
version_string()
- Returns the server software’s version string. This is a combination of the
server_version and sys_version class variables.
-
date_time_string([timestamp])
Returns the date and time given by timestamp (which must be in the
format returned by time.time()), formatted for a message header. If
timestamp is omitted, it uses the current date and time.
The result looks like 'Sun, 06 Nov 1994 08:49:37 GMT'.
New in version 2.5: The timestamp parameter.
-
log_date_time_string()
- Returns the current date and time, formatted for logging.
-
address_string()
- Returns the client address, formatted for logging. A name lookup is
performed on the client’s IP address.
See also
- Module CGIHTTPServer
- Extended request handler that supports CGI scripts.
- Module SimpleHTTPServer
- Basic request handler that limits response to files actually under the document
root.
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