ssh-utilities

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Version Info:
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Table of contents

• Introduction
• Design goals and features
• List of inner classes and implemented methods
• API and documentation
• Simple Usage
• Installation
• Contributing
• License
• TODO
• Known Issues

Introduction

Simple paramiko wrapper that aims to facilitate easy remote file operations and command execution. The API vaguely follows python libraries: builtins, os, os.path, subprocess, shutil, pathlib,

This is not intended to be a full fledged python ssh client. Instead it focuses on smaller set of features which it tries to make as user-friendly and familiar as possible.

This module should be ideally platform agnostic, but only connections from Windows and Linux(Debian, Ubuntu) to Linux(Debian, Ubuntu) have been tested so any other combinations are officially unsupported but should still work.

Design goals and features

• support python > 3.6
• everything is typed for easy code understanding and superior type hints and autocompletion
• everything is properly documented
• API is as consistent as possible with python modules and functions we are trying to reimplement
• connection can be made thread safe
• try to be as platform agnostic as possible
• accept both stings and Path objects in all methods that require some path as an input
• strong emphasis on usage of ssh key based authentication whether through key files or ssh-agent

List of inner classes and implemented methods

ssh_utilities have three main connection classes:

• SSHConnection
• LocalConnection
• MultiConnection

Their inner classes with their methods are listed in the table below which summarizes the API. Based on table you can do for instance:

>>> # this is OK
>>> SSHConnection.os.path.isfile(<somepath>)
>>> # this is not OK as it is marked in table as not implemented
>>> MultiConnection.os.path.realpath(<somepath>)
>>> # this is also not permitted as methods not mentioned in table are not
>>> # implemented in any class
>>> SSHConnection.os.getpid()

module	method	SSHConnection	LocalConnection	MultiConnection
builtins	open	✅	✅	✅
os	scandir	✅	✅	✅
	chmod	✅	✅	✅
	lchmod	✅	✅	✅
	symlink	✅	✅	✅
	rename	✅	✅	✅
	replace	✅	✅	✅
	makedirs	✅	✅	✅
	mkdir	✅	✅	✅
	listdir	✅	✅	✅
	chdir	✅	✅	✅
	stat	✅	✅	✅
	lstat	✅	✅	✅
	remove	✅	✅	✅
	unlink	✅	✅	✅
	rmdir	✅	✅	✅
	name	✅	✅	✅
	walk	✅	✅	✅
	path	✅	✅	❌
	supports_fd	✅	✅	❌
	supports_dir_fd	✅	✅	❌
os.path	realpath	✅	✅	❌
	isdir	✅	✅	❌
	isfile	✅	✅	❌
	exists	✅	✅	❌
	islink	✅	✅	❌
	getsize	✅	✅	❌
	join	✅	✅	❌
pathlib	Path	✅	✅	✅
shutil	copy	✅	✅	✅
	copy2	✅	✅	✅
	copyfile	✅	✅	✅
	copyfileobj	✅	✅	✅
	ignore_patterns	✅	✅	✅
	rmtree	✅	✅	✅
	upload_tree	✅	✅	✅
	download_tree	✅	✅	✅
subprocess	run	✅	✅	✅

API and documentation

It is recommended that you have configured rsa keys with config file according to openssh standard. For easy quickstart guide you can look at: https://www.cyberciti.biz/faq/create-ssh-config-file-on-linux-unix/

API exposes four main connection classes one path manipulation class, python module replacement classes, utility functions and constants:

from ssh_utilities import SSHConnection, Connection, LocalConnection, MultiConnection
from ssh_utilities import SSHPath
from ssh_utilities.remote import Builtins, Os, Pathlib, Shutil, Subprocess
# or
from ssh_utilities.local import Builtins, Os, Pathlib, Shutil, Subprocess
from ssh_utilities import config_parser
from ssh_utilities import PIPE, STDOUT, DEVNULL, GET, PUT

Connection is the a factory class that initializes SSHConnection or LocalConnection classes based on input parameters. MultiConnection is a container for convenient management of pool of connections. SSHPath is an object for remote path manipulation.

All API documentation can be found at readthedocs: https://ssh-utilities.readthedocs.io/en/latest/

Simple Usage

for more detailed usage examples please refer to documnetation

There are 3 authentication options:

• ssh key file
• ssh-agent
• password

Connection factory supports dict-like indexing by values that are in your ~/.ssh/config file.

>>> from ssh_utilities import Connection
>>> Connection[<server_name>]
>>> <ssh_utilities.ssh_utils.SSHConnection at 0x7efedff4fb38>

Class can also be normally instantiated which is safer and with better typing support than dict-like indexing. Connection can be made thread safe by passing thread_safe=True argument to the constructor

>>> from ssh_utilities import Connection
>>> Connection(<server_name>, <local>, <quiet>, <thread_safe>, <allow_agent>)
>>> <ssh_utilities.ssh_utils.SSHConnection at 0x7efedff4fb38>

Class can be also used as a context manager.

>>> from ssh_utilities import Connection
>>> with Connection(<server_name>, <local>, <quiet>, <thread_safe>, <allow_agent>) as conn:
>>>     conn.something(...)

Connection can also be initialized from appropriately formated string. Strings are used mainly for underlying connection classes persistance to disk

>>> from ssh_utilities import Connection
>>> Connection.from_str(<string>)

All these return connection with preset reasonable parameters if more customization is required, use open method, this also allows use of passwords

>>> from ssh_utilities import Connection
>>> conn = Connection.open(<ssh_username>, <ssh_server>, <ssh_key_file>,
                           <server_name>, <thread_safe>, <allow_agent>):

Module API also exposes powerfull SSHPath object with identical API as pathlib.Path only this one works for remote files. It must be always tied to some connection object which will provide interaction with remote host. The easyiest way to initialize it is as a method of Connection object.

>>> from ssh_utilities import Connection
>>> with Connection(<server_name>) as conn:
>>>     sshpath = conn.pathlib.Path(<some_path>)

Or the seccond option is to pass the SSHPath constructor an instace of created connection

>>> from ssh_utilities import Connection, SSHPath
>>> conn = Connection(<server_name>)
>>> sshpath = SSHPath(conn, <some_path>)

The replacements for parts of python standard lib can be used as inner classes of SSHConnection or LocalConnection:

>>> from ssh_utilities import Connection
>>> with Connection(<server_name>, <local>, <quiet>, <thread_safe>) as conn:
>>>     conn.os.path.isfile(<path_to_some_file>)
>>>     conn.subprocess.run(*args, **kwargs)
>>>     # and so on for other modules

Or you can assign the inner class to another variable but keep in mind that when connection is closed it will stop working!

>>> from ssh_utilities import Connection
>>> conn = Connection(<server_name>, <local>, <quiet>, <thread_safe>)
>>> remote_os =conn.os
>>> remote_subprocess = conn.subprocess

The last possibility is to instantiate each module by itself

>>> from ssh_utilities import Connection, Os, Subprocess
>>> conn = Connection(<server_name>, <local>, <quiet>, <thread_safe>)
>>> remote_os = Os(conn)
>>> remote_subprocess = Subprocess(conn)

ssh_utilities now contains MultiConnection container which cleverly manages multiple individual connections for you. You can carry out same command across multiple servers asynchronously and many more! Detailed information is in the docs.

>>> from ssh_utilities import MultiConnection
>>> with MultiConnection(<server_names_list>, local=False,
                         thread_safe=True) as mc:
>>>     mc.<some_attribute>
>>>     ...

Installation

pip install ssh_utilities

Or if you want to install directly from source:

git clone https://github.com/marian-code/ssh-utilities.git
cd ssh_utilities
pip install -e .

Use -e only to install in editable mode

If you encounter some import errors try installing from requirements.txt file: pip install -r requirements.txt

Contributing

1. Fork it
2. Create your feature branch: git checkout -b my-new-feature
3. Commit your changes: git commit -am 'Add some feature'
4. Push to the branch: git push origin my-new-feature
5. Submit a pull request

License

LGPL-2.1

TODO

• show which methods are implemented
• SSHPath root and anchor attributes incorectlly return '.' instead of '/'
• in some situation threadsafe object can cause deadlocks notable cases are: upload_tree/download_tree
• create expiring connecton that will self close after some time
• add ssh-agent docs
• _PosixFlavour in pathlib.py uses os.getcwd (python 3.7) we need to get around this and possibly write our own flavour

Known Issues

• SSHConnection.pathlib.path.resolve() can throw RuntimeError: Symlink loop in some cases
• threadsafe connection might in some instances cause a deadlock