etesync-cli

#!/usr/bin/env python

import argparse
import getpass
import os
import base64
import json
import vobject

import etesync as api

from cryptography.fernet import InvalidToken

remoteUrl = api.API_URL

USERS_FILE = os.path.join(os.path.expanduser('~'), '.etesync-cli', 'users_cache')

directory = os.path.dirname(USERS_FILE)
if directory != '' and not os.path.exists(directory):
    os.makedirs(directory)


def printJournal(entry):
    journal = entry.info
    print('\t{} ({})'.format(journal['displayName'], entry.uid))
    if journal.get('readOnly', False):
        print('\t\tRead only')


def printEntry(journal, entry):
    content = json.loads(entry.content)
    vobj = vobject.readOne(content['content'])

    print('{} {}'.format(content['action'],
                         journal.collection.get_content_class().get_uid(content['content'])))
    vobj.prettyPrint()

    print()


class EncryptedCache:
    def __init__(self, filename):

        self.filename = filename
        self.load()

    def init_encryption(self, username, password):
        from cryptography.fernet import Fernet
        from cryptography.hazmat.backends import default_backend
        from cryptography.hazmat.primitives import hashes
        from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC

        salt = username.encode()
        kdf = PBKDF2HMAC(
                algorithm=hashes.SHA256(),
                length=32,
                salt=salt,
                iterations=100000,
                backend=default_backend()
                )
        key = base64.urlsafe_b64encode(kdf.derive(password.encode()))
        self.f = Fernet(key)

    def encrypt(self, data):
        return self.f.encrypt(data.encode())

    def decrypt(self, data):
        return self.f.decrypt(data)

    def load(self):
        if os.path.exists(self.filename):
            with open(self.filename, "r") as f:
                data = f.read()
                if not data:
                    self.content = {'users': {}}
                else:
                    self.content = json.loads(data)
        else:
            self.content = {'users': {}}

    def save(self):
        with open(self.filename, "w") as f:
            f.write(json.dumps(self.content))

    def list(self):
        users = self.content['users']
        return users.keys()

    def get(self, username):
        users = self.content['users']
        user = users.get(username)
        if user is None:
            return user
        user = json.loads(self.decrypt(user.encode()))
        return user['authToken'], base64.b64decode(user['cipherKey'])

    def set(self, username, auth_token, cipher_key):
        users = self.content['users']
        user = self.encrypt(json.dumps({
                'authToken': auth_token,
                'cipherKey': base64.b64encode(cipher_key).decode(),
            })).decode()
        users[username] = user

    def delete(self, username):
        users = self.content['users']
        users.pop(username, None)


parser = argparse.ArgumentParser(description="""A command line tool to access the change journal and contents of your EteSync account.

You will be prompted for passwords as needed, or alternatively, you can set your password in the environment variable
"ETESYNC_ENC_PASS".""")
subparsers = parser.add_subparsers(help='available commands use "command -h" for help', dest='command')
parser_sync = subparsers.add_parser('sync', help='Sync the local cache with the remote server')
parser_sync.add_argument("username", help="The username used with EteSync")

parser_list = subparsers.add_parser('list', help='List collections (e.g. Calendars)')
parser_list.add_argument("username", help="The username used with EteSync")
parser_list.add_argument("journal", nargs='?', help="The UID of the journal (or any prefix of it)")

parser_journal = subparsers.add_parser('journal', help='View the change journal')
parser_journal.add_argument("username", help="The username used with EteSync")
parser_journal.add_argument("journal", help="The UID of the journal (or any prefix of it)")

parser_user = subparsers.add_parser('user', help='Add, list and remove users from the client')
user_subparsers = parser_user.add_subparsers(help='sub-command -h for help', dest='sub_command')
parser_user_list = user_subparsers.add_parser('list', help='List all users')
parser_user_add = user_subparsers.add_parser('add', help='Add a user')
parser_user_add.add_argument("username", help="The username used with EteSync")
parser_user_del = user_subparsers.add_parser('del', help='Delete a user')
parser_user_del.add_argument("username", help="The username used with EteSync")

args = parser.parse_args()

try:
    creds = EncryptedCache(USERS_FILE)
except InvalidToken:
    raise RuntimeError("Wrong encryption password or corrupt database.")

if args.command == 'user':
    if args.sub_command == 'add':
        servicePassword = getpass.getpass(prompt="Please enter the EteSync login password: ")
        encryptionPassword = getpass.getpass(prompt="Please enter your encryption password: ")

        creds.init_encryption(args.username, encryptionPassword)
        exists = creds.get(args.username)
        if exists:
            raise RuntimeError("User already exists. Delete first if you'd like to override settings.")

        authToken = api.Authenticator(remoteUrl).get_auth_token(args.username, servicePassword)

        etesync = api.EteSync(args.username, authToken, remote=remoteUrl)

        etesync.derive_key(encryptionPassword)
        creds.set(args.username, etesync.auth_token, etesync.cipher_key)
        creds.save()

    elif args.sub_command == 'del':
        creds.delete(args.username)
        creds.save()

    elif args.sub_command == 'list':
        for user in creds.list():
            print(user)
else:
    encryptionPassword = (os.environ.get('ETESYNC_ENC_PASS') or
                          getpass.getpass(prompt="Please enter your encryption password: "))

    creds.init_encryption(args.username, encryptionPassword)

    if creds.get(args.username) is None:
        raise RuntimeError("User doesn't exist, please add it first.")

    authToken, cipherKey = creds.get(args.username)
    etesync = api.EteSync(args.username, authToken, cipher_key=cipherKey, remote=remoteUrl)

    if getattr(args, 'journal', None) is not None:
        journal = None
        for item in etesync.list():
            if item.uid.startswith(args.journal):
                journal = item

    if args.command == 'sync':
        etesync.sync()

    elif args.command == 'list':
        if args.journal:

            if journal is None:
                raise RuntimeError("No journal matching '{}' found!".format(args.journal))

            # Or interact with the collection
            print("Journal items: {}".format(len(list(journal.list()))))
            print("Collection items: {}".format(len(list(journal.collection.list()))))

            print('\n# Items')
            for item in journal.collection.list():
                vobj = vobject.readOne(item.content)
                vobj.prettyPrint()
        else:
            print('# Address Books')
            for contact in filter(lambda x: x.info.get('type') == api.AddressBook.TYPE, etesync.list()):
                printJournal(contact)

            print()
            print('# Calendars')
            for calendar in filter(lambda x: x.info.get('type') == api.Calendar.TYPE, etesync.list()):
                printJournal(calendar)

    elif args.command == 'journal':
            print("Journal items: {}".format(len(list(journal.list()))))
            print("Collection items: {}".format(len(list(journal.collection.list()))))

            print('\n# Items')
            for item in reversed(list(journal.list())):
                printEntry(journal, item)