from __future__ import annotations
from enum import Enum
from docker import APIClient, DockerClient
from docker.transport import SSHHTTPAdapter
from paramiko import AutoAddPolicy, SSHClient
from time import sleep
import re
from .rabbitmq_utils import RMQPublisher
from pymongo import MongoClient
__all__ = [
'create_docker_client',
'create_ssh_client',
'DeployType',
'verify_mongodb_available',
'verify_rabbitmq_available'
]
[docs]def create_ssh_client(address: str, username: str, password: str = "", keypath: str = "") -> SSHClient:
client = SSHClient()
client.set_missing_host_key_policy(AutoAddPolicy)
try:
client.connect(hostname=address, username=username, password=password, key_filename=keypath)
except Exception as error:
raise Exception(f"Error creating SSHClient of host '{address}', reason:") from error
return client
[docs]def create_docker_client(address: str, username: str, password: str = "", keypath: str = "") -> CustomDockerClient:
return CustomDockerClient(username, address, password=password, keypath=keypath)
class CustomDockerClient(DockerClient):
"""Wrapper for docker.DockerClient to use an own SshHttpAdapter.
This makes it possible to use provided password/keyfile for connecting with
python-docker-sdk, which otherwise only allows to use ~/.ssh/config for
login
XXX: inspired by https://github.com/docker/docker-py/issues/2416 . Should be replaced when
docker-sdk provides its own way to make it possible to use custom SSH Credentials. Possible
Problems: APIClient must be given the API-version because it cannot connect prior to read it. I
could imagine this could cause Problems. This is not a rushed implementation and was the only
workaround I could find that allows password/keyfile to be used (by default only keyfile from
~/.ssh/config can be used to authenticate via ssh)
XXX 2: Reasons to extend DockerClient: The code-changes regarding the connection should be in
one place, so I decided to create `CustomSshHttpAdapter` as an inner class. The super
constructor *must not* be called to make this workaround work. Otherwise, the APIClient
constructor would be invoked without `version` and that would cause a connection-attempt before
this workaround can be applied.
"""
def __init__(self, user: str, host: str, **kwargs) -> None:
# the super-constructor is not called on purpose: it solely instantiates the APIClient. The
# missing `version` in that call would raise an error. APIClient is provided here as a
# replacement for what the super-constructor does
if not (user and host):
raise ValueError('Missing argument: user and host must both be provided')
if ('password' not in kwargs) != ('keypath' not in kwargs):
raise ValueError('Missing argument: one of password and keyfile is needed')
self.api = APIClient(f'ssh://{host}', use_ssh_client=True, version='1.41')
ssh_adapter = self.CustomSshHttpAdapter(f'ssh://{user}@{host}:22', **kwargs)
self.api.mount('http+docker://ssh', ssh_adapter)
class CustomSshHttpAdapter(SSHHTTPAdapter):
def __init__(self, base_url, password: str = "", keypath: str = "") -> None:
self.password = password
self.keypath = keypath
if bool(self.password) == bool(self.keypath):
raise Exception("Either 'password' or 'keypath' must be provided")
super().__init__(base_url)
def _create_paramiko_client(self, base_url: str) -> None:
"""
this method is called in the superclass constructor. Overwriting allows to set
password/keypath for the internal paramiko-client
"""
super()._create_paramiko_client(base_url)
if self.password:
self.ssh_params['password'] = self.password
elif self.keypath:
self.ssh_params['key_filename'] = self.keypath
self.ssh_client.set_missing_host_key_policy(AutoAddPolicy)
[docs]def verify_rabbitmq_available(
host: str,
port: int,
vhost: str,
username: str,
password: str
) -> None:
max_waiting_steps = 15
while max_waiting_steps > 0:
try:
dummy_publisher = RMQPublisher(host=host, port=port, vhost=vhost)
dummy_publisher.authenticate_and_connect(username=username, password=password)
except Exception:
max_waiting_steps -= 1
sleep(2)
else:
# TODO: Disconnect the dummy_publisher here before returning...
return
raise RuntimeError(f'Cannot connect to RabbitMQ host: {host}, port: {port}, '
f'vhost: {vhost}, username: {username}')
[docs]def verify_mongodb_available(mongo_url: str) -> None:
try:
client = MongoClient(mongo_url, serverSelectionTimeoutMS=1000.0)
client.admin.command("ismaster")
except Exception:
raise RuntimeError(f'Cannot connect to MongoDB: {re.sub(r":[^@]+@", ":****@", mongo_url)}')
[docs]class DeployType(Enum):
""" Deploy-Type of the processing worker/processor server.
"""
DOCKER = 1
NATIVE = 2
