CDDB.py

#!/usr/bin/env python3
"""
Module for retrieving CDDB v1 data from CDDB servers via HTTP

Written 17 Nov 1999 by Ben Gertzfield <che@debian.org>
This work is released under the GNU GPL, version 2 or later.
"""

import urllib.request, urllib.parse, urllib.error
import string
import socket
import os
import struct
import re

name = 'CDDB.py'
version = 1.4

if 'EMAIL' in os.environ:
    (default_user, hostname) = string.split(os.environ['EMAIL'], '@')
else:
    default_user = os.geteuid() or os.environ['USER'] or 'user'
    hostname = socket.gethostname() or 'host'

# Use protocol version 5 to get DYEAR and DGENRE fields.
proto = 5
default_server = 'http://freedb.freedb.org/~cddb/cddb.cgi'


def query(track_info, server_url=default_server,
          user=default_user, host=hostname, client_name=name,
          client_version=version):

    disc_id = track_info[0]
    num_tracks = track_info[1]

    query_str = (('%08lx %d ') % (disc_id, num_tracks))

    for i in track_info[2:]:
        query_str = query_str + ('%d ' % i)

    query_str = urllib.parse.quote_plus(string.rstrip(query_str))

    url = "%s?cmd=cddb+query+%s&hello=%s+%s+%s+%s&proto=%i" % \
          (server_url, query_str, user, host, client_name,
           client_version, proto)

    response = urllib.request.urlopen(url)

    # Four elements in header: status, category, disc-id, title
    header = string.split(string.rstrip(response.readline()), ' ', 3)

    header[0] = string.atoi(header[0])

    if header[0] == 200:                # OK
        result = {'category': header[1], 'disc_id': header[2], 'title':
                  header[3]}

        return [header[0], result]

    elif header[0] == 211 or header[0] == 210:  # multiple matches
        result = []

        for line in response.readlines():
            line = string.rstrip(line)

            if line == '.':             # end of matches
                break
                # otherwise:
                # split into 3 pieces, not 4
                # (thanks to bgp for the fix!)
            match = string.split(line, ' ', 2)

            result.append({'category': match[0], 'disc_id': match[1], 'title':
                           match[2]})

        return [header[0], result]

    else:
        return [header[0], None]


def read(category, disc_id, server_url=default_server,
         user=default_user, host=hostname, client_name=name,
         client_version=version):

    url = "%s?cmd=cddb+read+%s+%s&hello=%s+%s+%s+%s&proto=%i" % \
          (server_url, category, disc_id, user, host, client_name,
           client_version, proto)

    response = urllib.request.urlopen(url)

    header = string.split(string.rstrip(response.readline()), ' ', 3)

    header[0] = string.atoi(header[0])
    if header[0] == 210 or header[0] == 417:  # success or access denied
        reply = []

        for line in response.readlines():
            line = string.rstrip(line)

            if line == '.':
                break

            line = string.replace(line, r'\t', "\t")
            line = string.replace(line, r'\n', "\n")
            line = string.replace(line, r'\\', "\\")

            reply.append(line)

        if header[0] == 210:            # success, parse the reply
            return [header[0], parse_read_reply(reply)]
        else:                           # access denied. :(
            return [header[0], reply]
    else:
        return [header[0], None]


def parse_read_reply(comments):

    len_re = re.compile(r'#\s*Disc length:\s*(\d+)\s*seconds')
    revis_re = re.compile(r'#\s*Revision:\s*(\d+)')
    submit_re = re.compile(r'#\s*Submitted via:\s*(.+)')
    keyword_re = re.compile(r'([^=]+)=(.*)')

    result = {}

    for line in comments:
        keyword_match = keyword_re.match(line)
        if keyword_match:
            (keyword, data) = keyword_match.groups()

            if keyword in result:
                result[keyword] = result[keyword] + data
            else:
                result[keyword] = data
            continue

        len_match = len_re.match(line)
        if len_match:
            result['disc_len'] = int(len_match.group(1))
            continue

        revis_match = revis_re.match(line)
        if revis_match:
            result['revision'] = int(revis_match.group(1))
            continue

        submit_match = submit_re.match(line)
        if submit_match:
            result['submitted_via'] = submit_match.group(1)
            continue

    return result