| :mod:`BaseHTTPServer` --- Basic HTTP server |
| =========================================== |
| |
| .. module:: BaseHTTPServer |
| :synopsis: Basic HTTP server (base class for SimpleHTTPServer and CGIHTTPServer). |
| |
| .. note:: |
| The :mod:`BaseHTTPServer` module has been merged into :mod:`http.server` in |
| Python 3.0. The :term:`2to3` tool will automatically adapt imports when |
| converting your sources to 3.0. |
| |
| |
| .. index:: |
| pair: WWW; server |
| pair: HTTP; protocol |
| single: URL |
| single: httpd |
| module: SimpleHTTPServer |
| module: CGIHTTPServer |
| |
| 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 :mod:`SimpleHTTPServer` and |
| :mod:`CGIHTTPServer` modules. |
| |
| The first class, :class:`HTTPServer`, is a :class:`SocketServer.TCPServer` |
| subclass, and therefore implements the :class:`SocketServer.BaseServer` |
| interface. 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:: HTTPServer(server_address, RequestHandlerClass) |
| |
| This class builds on the :class:`TCPServer` class by storing the server |
| address as instance variables named :attr:`server_name` and |
| :attr:`server_port`. The server is accessible by the handler, typically |
| through the handler's :attr:`server` instance variable. |
| |
| |
| .. class:: 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). :class:`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 :meth:`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 :meth:`__init__` method. |
| |
| :class:`BaseHTTPRequestHandler` has the following instance variables: |
| |
| |
| .. attribute:: client_address |
| |
| Contains a tuple of the form ``(host, port)`` referring to the client's |
| address. |
| |
| |
| .. attribute:: server |
| |
| Contains the server instance. |
| |
| |
| .. attribute:: command |
| |
| Contains the command (request type). For example, ``'GET'``. |
| |
| |
| .. attribute:: path |
| |
| Contains the request path. |
| |
| |
| .. attribute:: request_version |
| |
| Contains the version string from the request. For example, ``'HTTP/1.0'``. |
| |
| |
| .. attribute:: headers |
| |
| Holds an instance of the class specified by the :attr:`MessageClass` class |
| variable. This instance parses and manages the headers in the HTTP |
| request. |
| |
| |
| .. attribute:: rfile |
| |
| Contains an input stream, positioned at the start of the optional input |
| data. |
| |
| |
| .. attribute:: 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. |
| |
| |
| :class:`BaseHTTPRequestHandler` has the following class variables: |
| |
| |
| .. attribute:: 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'``. |
| |
| |
| .. attribute:: sys_version |
| |
| Contains the Python system version, in a form usable by the |
| :attr:`version_string` method and the :attr:`server_version` class |
| variable. For example, ``'Python/1.4'``. |
| |
| |
| .. attribute:: 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. |
| |
| |
| .. attribute:: error_content_type |
| |
| Specifies the Content-Type HTTP header of error responses sent to the |
| client. The default value is ``'text/html'``. |
| |
| .. versionadded:: 2.6 |
| Previously, the content type was always ``'text/html'``. |
| |
| |
| .. attribute:: 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 :meth:`send_header`) in all of its responses to clients. |
| For backwards compatibility, the setting defaults to ``'HTTP/1.0'``. |
| |
| |
| .. attribute:: MessageClass |
| |
| .. index:: single: Message (in module mimetools) |
| |
| Specifies a :class:`rfc822.Message`\ -like class to parse HTTP headers. |
| Typically, this is not overridden, and it defaults to |
| :class:`mimetools.Message`. |
| |
| |
| .. attribute:: 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 |
| :attr:`error_message_format` class variable). |
| |
| |
| A :class:`BaseHTTPRequestHandler` instance has the following methods: |
| |
| |
| .. method:: handle() |
| |
| Calls :meth:`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 :meth:`do_\*` |
| methods. |
| |
| |
| .. method:: handle_one_request() |
| |
| This method will parse and dispatch the request to the appropriate |
| :meth:`do_\*` method. You should never need to override it. |
| |
| |
| .. method:: 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 |
| :attr:`error_message_format` class variable. |
| |
| |
| .. method:: 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 :meth:`version_string` and |
| :meth:`date_time_string` methods, respectively. |
| |
| |
| .. method:: send_header(keyword, value) |
| |
| Writes a specific HTTP header to the output stream. *keyword* should |
| specify the header keyword, with *value* specifying its value. |
| |
| |
| .. method:: end_headers() |
| |
| Sends a blank line, indicating the end of the HTTP headers in the |
| response. |
| |
| |
| .. method:: 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. |
| |
| |
| .. method:: log_error(...) |
| |
| Logs an error when a request cannot be fulfilled. By default, it passes |
| the message to :meth:`log_message`, so it takes the same arguments |
| (*format* and additional values). |
| |
| |
| .. method:: 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 |
| :meth:`log_message` are applied as inputs to the formatting. The client |
| address and current date and time are prefixed to every message logged. |
| |
| |
| .. method:: version_string() |
| |
| Returns the server software's version string. This is a combination of the |
| :attr:`server_version` and :attr:`sys_version` class variables. |
| |
| |
| .. method:: date_time_string([timestamp]) |
| |
| Returns the date and time given by *timestamp* (which must be in the |
| format returned by :func:`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'``. |
| |
| .. versionadded:: 2.5 |
| The *timestamp* parameter. |
| |
| |
| .. method:: log_date_time_string() |
| |
| Returns the current date and time, formatted for logging. |
| |
| |
| .. method:: address_string() |
| |
| Returns the client address, formatted for logging. A name lookup is |
| performed on the client's IP address. |
| |
| |
| More examples |
| ------------- |
| |
| To create a server that doesn't run forever, but until some condition is |
| fulfilled:: |
| |
| def run_while_true(server_class=BaseHTTPServer.HTTPServer, |
| handler_class=BaseHTTPServer.BaseHTTPRequestHandler): |
| """ |
| This assumes that keep_running() is a function of no arguments which |
| is tested initially and after each request. If its return value |
| is true, the server continues. |
| """ |
| server_address = ('', 8000) |
| httpd = server_class(server_address, handler_class) |
| while keep_running(): |
| httpd.handle_request() |
| |
| |
| .. seealso:: |
| |
| Module :mod:`CGIHTTPServer` |
| Extended request handler that supports CGI scripts. |
| |
| Module :mod:`SimpleHTTPServer` |
| Basic request handler that limits response to files actually under the |
| document root. |
| |
