"""Simple HTTP Server.

This module builds on BaseHTTPServer by implementing the standard GET

and HEAD requests in a fairly straightforward manner.

"""

__version__ = "0.6"

__all__ = ["SimpleHTTPRequestHandler"]

import os

import posixpath

import BaseHTTPServer

import urllib

import urlparse

import cgi

import shutil

import mimetypes

try:

    from cStringIO import StringIO

except ImportError:

    from StringIO import StringIO

class SimpleHTTPRequestHandler(BaseHTTPServer.BaseHTTPRequestHandler):

    """Simple HTTP request handler with GET and HEAD commands.

    This serves files from the current directory and any of its

    subdirectories.  The MIME type for files is determined by

    calling the .guess_type() method.

    The GET and HEAD requests are identical except that the HEAD

    request omits the actual contents of the file.

    """

    server_version = "SimpleHTTP/" + __version__

    def do_GET(self):

        """Serve a GET request."""

        f = self.send_head()

        if f:

            self.copyfile(f, self.wfile)

            f.close()

    def do_HEAD(self):

        """Serve a HEAD request."""

        f = self.send_head()

        if f:

            f.close()

    def send_head(self):

        """Common code for GET and HEAD commands.

        This sends the response code and MIME headers.

        Return value is either a file object (which has to be copied

        to the outputfile by the caller unless the command was HEAD,

        and must be closed by the caller under all circumstances), or

        None, in which case the caller has nothing further to do.

        """

        path = self.translate_path(self.path)

        f = None

        if os.path.isdir(path):

            if not self.path.endswith('/'):

                # redirect browser - doing basically what apache does

                self.send_response(301)

                self.send_header("Location", self.path + "/")

                self.end_headers()

                return None

            for index in "index.html", "index.htm":

                index = os.path.join(path, index)

                if os.path.exists(index):

                    path = index

                    break

            else:

                return self.list_directory(path)

        ctype = self.guess_type(path)

        if ctype.startswith('text/'):

            mode = 'r'

        else:

            mode = 'rb'

        try:

            f = open(path, mode)

        except IOError:

            self.send_error(404, "File not found")

            return None

        self.send_response(200)

        self.send_header("Content-type", ctype)

        fs = os.fstat(f.fileno())

        self.send_header("Content-Length", str(fs[6]))

        self.send_header("Last-Modified", self.date_time_string(fs.st_mtime))

        self.end_headers()

        return f

    def list_directory(self, path):

        """Helper to produce a directory listing (absent index.html).

        Return value is either a file object, or None (indicating an

        error).  In either case, the headers are sent, making the

        interface the same as for send_head().

        """

        try:

            list = os.listdir(path)

        except os.error:

            self.send_error(404, "No permission to list directory")

            return None

        list.sort(key=lambda a: a.lower())

        f = StringIO()

        displaypath = cgi.escape(urllib.unquote(self.path))

        f.write("<title>Directory listing for %s</title>\n" % displaypath)

        f.write("<h2>Directory listing for %s</h2>\n" % displaypath)

        f.write("<hr>\n<ul>\n")

        for name in list:

            fullname = os.path.join(path, name)

            displayname = linkname = name

            # Append / for directories or @ for symbolic links

            if os.path.isdir(fullname):

                displayname = name + "/"

                linkname = name + "/"

            if os.path.islink(fullname):

                displayname = name + "@"

                # Note: a link to a directory displays with @ and links with /

            f.write('<li><a href="%s">%s</a>\n'

                    % (urllib.quote(linkname), cgi.escape(displayname)))

        f.write("</ul>\n<hr>\n")

        length = f.tell()

        f.seek(0)

        self.send_response(200)

        self.send_header("Content-type", "text/html")

        self.send_header("Content-Length", str(length))

        self.end_headers()

        return f

    def translate_path(self, path):

        """Translate a /-separated PATH to the local filename syntax.

        Components that mean special things to the local file system

        (e.g. drive or directory names) are ignored.  (XXX They should

        probably be diagnosed.)

        """

        # abandon query parameters

        path = urlparse.urlparse(path)[2]

        path = posixpath.normpath(urllib.unquote(path))

        words = path.split('/')

        words = filter(None, words)

        path = os.getcwd()

        for word in words:

            drive, word = os.path.splitdrive(word)

            head, word = os.path.split(word)

            if word in (os.curdir, os.pardir): continue

            path = os.path.join(path, word)

        return path

    def copyfile(self, source, outputfile):

        """Copy all data between two file objects.

        The SOURCE argument is a file object open for reading

        (or anything with a read() method) and the DESTINATION

        argument is a file object open for writing (or

        anything with a write() method).

        The only reason for overriding this would be to change

        the block size or perhaps to replace newlines by CRLF

        -- note however that this the default server uses this

        to copy binary data as well.

        """

        shutil.copyfileobj(source, outputfile)

    def guess_type(self, path):

        """Guess the type of a file.

        Argument is a PATH (a filename).

        Return value is a string of the form type/subtype,

        usable for a MIME Content-type header.

        The default implementation looks the file's extension

        up in the table self.extensions_map, using application/octet-stream

        as a default; however it would be permissible (if

        slow) to look inside the data to make a better guess.

        """

        base, ext = posixpath.splitext(path)

        if ext in self.extensions_map:

            return self.extensions_map[ext]

        ext = ext.lower()

        if ext in self.extensions_map:

            return self.extensions_map[ext]

        else:

            return self.extensions_map['']

    if not mimetypes.inited:

        mimetypes.init() # try to read system mime.types

    extensions_map = mimetypes.types_map.copy()

    extensions_map.update({

        '': 'application/octet-stream', # Default

        '.py': 'text/plain',

        '.c': 'text/plain',

        '.h': 'text/plain',

        })

def test(HandlerClass = SimpleHTTPRequestHandler,

         ServerClass = BaseHTTPServer.HTTPServer):

    BaseHTTPServer.test(HandlerClass, ServerClass)

if __name__ == '__main__':

    test()