## Amazon S3 manager
## Author: Michal Ludvig <michal@logix.cz>
##         http://www.logix.cz/michal
## License: GPL Version 2

import logging
from logging import debug, info, warning, error
import re
import os
import sys
import Progress
from SortedDict import SortedDict
import httplib
import json

class Config(object):
    _instance = None
    _parsed_files = []
    _doc = {}
    access_key = ""
    secret_key = ""
    access_token = ""
    host_base = "s3.amazonaws.com"
    host_bucket = "%(bucket)s.s3.amazonaws.com"
    simpledb_host = "sdb.amazonaws.com"
    cloudfront_host = "cloudfront.amazonaws.com"
    verbosity = logging.WARNING
    progress_meter = True
    progress_class = Progress.ProgressCR
    send_chunk = 4096
    recv_chunk = 4096
    list_md5 = False
    human_readable_sizes = False
    extra_headers = SortedDict(ignore_case = True)
    force = False
    enable = None
    get_continue = False
    skip_existing = False
    recursive = False
    acl_public = None
    acl_grants = []
    acl_revokes = []
    proxy_host = ""
    proxy_port = 3128
    encrypt = False
    dry_run = False
    add_encoding_exts = ""
    preserve_attrs = True
    preserve_attrs_list = [
        'uname',    # Verbose owner Name (e.g. 'root')
        'uid',      # Numeric user ID (e.g. 0)
        'gname',    # Group name (e.g. 'users')
        'gid',      # Numeric group ID (e.g. 100)
        'atime',    # Last access timestamp
        'mtime',    # Modification timestamp
        'ctime',    # Creation timestamp
        'mode',     # File mode (e.g. rwxr-xr-x = 755)
        'md5',      # File MD5 (if known)
        #'acl',     # Full ACL (not yet supported)
    ]
    delete_removed = False
    delete_after = False
    delete_after_fetch = False
    _doc['delete_removed'] = "[sync] Remove remote S3 objects when local file has been deleted"
    delay_updates = False
    gpg_passphrase = ""
    gpg_command = ""
    gpg_encrypt = "%(gpg_command)s -c --verbose --no-use-agent --batch --yes --passphrase-fd %(passphrase_fd)s -o %(output_file)s %(input_file)s"
    gpg_decrypt = "%(gpg_command)s -d --verbose --no-use-agent --batch --yes --passphrase-fd %(passphrase_fd)s -o %(output_file)s %(input_file)s"
    use_https = False
    bucket_location = "US"
    default_mime_type = "binary/octet-stream"
    guess_mime_type = True
    mime_type = ""
    enable_multipart = True
    multipart_chunk_size_mb = 15    # MB
    # List of checks to be performed for 'sync'
    sync_checks = ['size', 'md5']   # 'weak-timestamp'
    # List of compiled REGEXPs
    exclude = []
    include = []
    # Dict mapping compiled REGEXPs back to their textual form
    debug_exclude = {}
    debug_include = {}
    encoding = "utf-8"
    urlencoding_mode = "normal"
    log_target_prefix = ""
    reduced_redundancy = False
    follow_symlinks = False
    socket_timeout = 300
    invalidate_on_cf = False
    # joseprio: new flags for default index invalidation
    invalidate_default_index_on_cf = False
    invalidate_default_index_root_on_cf = True
    website_index = "index.html"
    website_error = ""
    website_endpoint = "http://%(bucket)s.s3-website-%(location)s.amazonaws.com/"
    additional_destinations = []
    cache_file = ""
    add_headers = ""

    ## Creating a singleton
    def __new__(self, configfile = None):
        if self._instance is None:
            self._instance = object.__new__(self)
        return self._instance

    def __init__(self, configfile = None):
        if configfile:
            try:
                self.read_config_file(configfile)
            except IOError, e:
                if 'AWS_CREDENTIAL_FILE' in os.environ:
                    self.env_config()
            if len(self.access_key)==0:
                self.role_config()  

    def role_config(self):
        conn = httplib.HTTPConnection(host='169.254.169.254',timeout=0.1)
        try:
            conn.request('GET', "/latest/meta-data/iam/security-credentials/")
            resp = conn.getresponse()
            files = resp.read()
            if resp.status == 200 and len(files)>1:               
                conn.request('GET', "/latest/meta-data/iam/security-credentials/%s"%files)
                resp=conn.getresponse()
                if resp.status == 200:
                    creds=json.load(resp)
                    Config().update_option('access_key', creds['AccessKeyId'].encode('ascii'))
                    Config().update_option('secret_key', creds['SecretAccessKey'].encode('ascii'))
                    Config().update_option('access_token', creds['Token'].encode('ascii'))
                else:
                    raise IOError
            else:
                raise IOError
        except:
            raise

    def role_refresh(self):
        try:
            self.role_config()
        except:
            warning("Could not refresh role")

    def env_config(self):
        cred_content = ""
        try:
            cred_file = open(os.environ['AWS_CREDENTIAL_FILE'],'r')
            cred_content = cred_file.read()
        except IOError, e:
            debug("Error %d accessing credentials file %s" % (e.errno,os.environ['AWS_CREDENTIAL_FILE']))
        r_data = re.compile("^\s*(?P<orig_key>\w+)\s*=\s*(?P<value>.*)")
        r_quotes = re.compile("^\"(.*)\"\s*$")
        if len(cred_content)>0:
            for line in cred_content.splitlines():
                is_data = r_data.match(line)
                is_data = r_data.match(line)
                if is_data:
                    data = is_data.groupdict()
                    if r_quotes.match(data["value"]):
                        data["value"] = data["value"][1:-1]
                    if data["orig_key"]=="AWSAccessKeyId":
                        data["key"] = "access_key"
                    elif data["orig_key"]=="AWSSecretKey":
                        data["key"] = "secret_key"
                    else:
                        del data["key"]                    
                    if "key" in data:
                        Config().update_option(data["key"], data["value"])
                        if data["key"] in ("access_key", "secret_key", "gpg_passphrase"):
                            print_value = (data["value"][:2]+"...%d_chars..."+data["value"][-1:]) % (len(data["value"]) - 3)
                        else:
                            print_value = data["value"]
                        debug("env_Config: %s->%s" % (data["key"], print_value))
                
        

    def option_list(self):
        retval = []
        for option in dir(self):
            ## Skip attributes that start with underscore or are not string, int or bool
            option_type = type(getattr(Config, option))
            if option.startswith("_") or \
               not (option_type in (
                    type("string"), # str
                        type(42),   # int
                    type(True))):   # bool
                continue
            retval.append(option)
        return retval

    def read_config_file(self, configfile):
        cp = ConfigParser(configfile)
        for option in self.option_list():
            self.update_option(option, cp.get(option))

        if cp.get('add_headers'):
            for option in cp.get('add_headers').split(","):
                (key, value) = option.split(':')
                self.extra_headers[key.replace('_', '-').strip()] = value.strip()

        self._parsed_files.append(configfile)

    def dump_config(self, stream):
        ConfigDumper(stream).dump("default", self)

    def update_option(self, option, value):
        if value is None:
            return
        #### Handle environment reference
        if str(value).startswith("$"):
            return self.update_option(option, os.getenv(str(value)[1:]))
        #### Special treatment of some options
        ## verbosity must be known to "logging" module
        if option == "verbosity":
            try:
                setattr(Config, "verbosity", logging._levelNames[value])
            except KeyError:
                error("Config: verbosity level '%s' is not valid" % value)
        ## allow yes/no, true/false, on/off and 1/0 for boolean options
        elif type(getattr(Config, option)) is type(True):   # bool
            if str(value).lower() in ("true", "yes", "on", "1"):
                setattr(Config, option, True)
            elif str(value).lower() in ("false", "no", "off", "0"):
                setattr(Config, option, False)
            else:
                error("Config: value of option '%s' must be Yes or No, not '%s'" % (option, value))
        elif type(getattr(Config, option)) is type(42):     # int
            try:
                setattr(Config, option, int(value))
            except ValueError, e:
                error("Config: value of option '%s' must be an integer, not '%s'" % (option, value))
        else:                           # string
            setattr(Config, option, value)

class ConfigParser(object):
    def __init__(self, file, sections = []):
        self.cfg = {}
        self.parse_file(file, sections)

    def parse_file(self, file, sections = []):
        debug("ConfigParser: Reading file '%s'" % file)
        if type(sections) != type([]):
            sections = [sections]
        in_our_section = True
        f = open(file, "r")
        r_comment = re.compile("^\s*#.*")
        r_empty = re.compile("^\s*$")
        r_section = re.compile("^\[([^\]]+)\]")
        r_data = re.compile("^\s*(?P<key>\w+)\s*=\s*(?P<value>.*)")
        r_quotes = re.compile("^\"(.*)\"\s*$")
        for line in f:
            if r_comment.match(line) or r_empty.match(line):
                continue
            is_section = r_section.match(line)
            if is_section:
                section = is_section.groups()[0]
                in_our_section = (section in sections) or (len(sections) == 0)
                continue
            is_data = r_data.match(line)
            if is_data and in_our_section:
                data = is_data.groupdict()
                if r_quotes.match(data["value"]):
                    data["value"] = data["value"][1:-1]
                self.__setitem__(data["key"], data["value"])
                if data["key"] in ("access_key", "secret_key", "gpg_passphrase"):
                    print_value = (data["value"][:2]+"...%d_chars..."+data["value"][-1:]) % (len(data["value"]) - 3)
                else:
                    print_value = data["value"]
                debug("ConfigParser: %s->%s" % (data["key"], print_value))
                continue
            warning("Ignoring invalid line in '%s': %s" % (file, line))

    def __getitem__(self, name):
        return self.cfg[name]

    def __setitem__(self, name, value):
        self.cfg[name] = value

    def get(self, name, default = None):
        if self.cfg.has_key(name):
            return self.cfg[name]
        return default

class ConfigDumper(object):
    def __init__(self, stream):
        self.stream = stream

    def dump(self, section, config):
        self.stream.write("[%s]\n" % section)
        for option in config.option_list():
            self.stream.write("%s = %s\n" % (option, getattr(config, option)))

# vim:et:ts=4:sts=4:ai