view libervia/backend/tools/common/data_format.py @ 4219:1b5cf2ee1d86

plugin XEP-0384, XEP-0391: download missing devices list: when a peer jid was not in our roster, devices list was not retrieved, resulting in failed en/decryption. This patch does check it and download missing devices list in necessary. There is no subscription managed yet, so the list won't be updated in case of new devices, this should be addressed at some point.
author Goffi <goffi@goffi.org>
date Tue, 05 Mar 2024 17:31:36 +0100
parents 4b842c1fb686
children 79c8a70e1813
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#!/usr/bin/env python3


# SAT: a jabber client
# Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

""" tools common to backend and frontends """
#  FIXME: json may be more appropriate than manual serialising like done here

from typing import Any

from libervia.backend.core import exceptions
import json


def dict2iter(name, dict_, pop=False):
    """iterate into a list serialised in a dict

    name is the name of the key.
    Serialisation is done with [name] [name#1] [name#2] and so on
    e.g.: if name is 'group', keys are group, group#1, group#2, ...
    iteration stop at first missing increment
    Empty values are possible
    @param name(unicode): name of the key
    @param dict_(dict): dictionary with the serialised list
    @param pop(bool): if True, remove the value from dict
    @return iter: iterate through the deserialised list
    """
    if pop:
        get = lambda d, k: d.pop(k)
    else:
        get = lambda d, k: d[k]

    try:
        yield get(dict_, name)
    except KeyError:
        return
    else:
        idx = 1
        while True:
            try:
                yield get(dict_, "{}#{}".format(name, idx))
            except KeyError:
                return
            else:
                idx += 1


def dict2iterdict(name, dict_, extra_keys, pop=False):
    """like dict2iter but yield dictionaries

    params are like in [dict2iter], extra_keys is used for extra dict keys.
    e.g. dict2iterdict(comments, mb_data, ('node', 'service')) will yield dicts like:
        {u'comments': u'value1', u'node': u'value2', u'service': u'value3'}
    """
    #  FIXME: this format seem overcomplicated, it may be more appropriate to use json here
    if pop:
        get = lambda d, k: d.pop(k)
    else:
        get = lambda d, k: d[k]
    for idx, main_value in enumerate(dict2iter(name, dict_, pop=pop)):
        ret = {name: main_value}
        for k in extra_keys:
            ret[k] = get(
                dict_, "{}{}_{}".format(name, ("#" + str(idx)) if idx else "", k)
            )
        yield ret


def iter2dict(name, iter_, dict_=None, check_conflict=True):
    """Fill a dict with values from an iterable

    name is used to serialise iter_, in the same way as in [dict2iter]
    Build from the tags a dict using the microblog data format.

    @param name(unicode): key to use for serialisation
        e.g. "group" to have keys "group", "group#1", "group#2", ...
    @param iter_(iterable): values to store
    @param dict_(None, dict): dictionary to fill, or None to create one
    @param check_conflict(bool): if True, raise an exception in case of existing key
    @return (dict): filled dict, or newly created one
    @raise exceptions.ConflictError: a needed key already exists
    """
    if dict_ is None:
        dict_ = {}
    for idx, value in enumerate(iter_):
        if idx == 0:
            key = name
        else:
            key = "{}#{}".format(name, idx)
        if check_conflict and key in dict_:
            raise exceptions.ConflictError
        dict_[key] = value
    return dict


def get_sub_dict(name, dict_, sep="_"):
    """get a sub dictionary from a serialised dictionary

    look for keys starting with name, and create a dict with it
    eg.: if "key" is looked for, {'html': 1, 'key_toto': 2, 'key_titi': 3} will return:
        {None: 1, toto: 2, titi: 3}
    @param name(unicode): name of the key
    @param dict_(dict): dictionary with the serialised list
    @param sep(unicode): separator used between name and subkey
    @return iter: iterate through the deserialised items
    """
    for k, v in dict_.items():
        if k.startswith(name):
            if k == name:
                yield None, v
            else:
                if k[len(name)] != sep:
                    continue
                else:
                    yield k[len(name) + 1 :], v

def serialise(data):
    """Serialise data so it can be sent to bridge

    @return(unicode): serialised data, can be transmitted as string to the bridge
    """
    return json.dumps(data, ensure_ascii=False, default=str)

def deserialise(serialised_data: str, default: Any = None, type_check: type = dict):
    """Deserialize data from bridge

    @param serialised_data(unicode): data to deserialise
    @default (object): value to use when serialised data is empty string
    @param type_check(type): if not None, the deserialised data must be of this type
    @return(object): deserialised data
    @raise ValueError: serialised_data is of wrong type
    """
    if serialised_data == "":
        return default
    ret = json.loads(serialised_data)
    if type_check is not None and not isinstance(ret, type_check):
        raise ValueError("Bad data type, was expecting {type_check}, got {real_type}"
            .format(type_check=type_check, real_type=type(ret)))
    return ret