Getting Started

Installing sshreader

The easiest way to get working with sshreader is to use pip to install the module. You can do that by running the following in your terminal

pip install sshreader

Note

If you already have sshreader installed and would like to update to the latest release, run the following:

pip install --upgrade sshreader

Contratulations! You are now ready to begin working with sshreader!

Working With SSH Objects

To start working with ssh connections (without multiprocessing or threading) right away simply import the SSH class and setup a connection!

from sshreader import SSH
with SSH('myhost.example.com', username='jdoe', password='jdoe1') as s:
    uname = s.ssh_command('uname -a')
    print(uname)  # Show the results of the command, including stdin, stdout, and stderr

Note

By using the with statement you do not have to worry about running SSH.close() when you are finished with an ssh connection.

Working With ServerJob Objects

ServerJob objects are a way to run multiple commands via ssh and return/tabulate the results. ServerJobs can be placed into a list and then processed using multiprocessing and multithreading via the sshread method.

To create a ServerJob object and run it is nearly as simple as working with SSH objects:

from sshreader import ServerJob, sshread
job = ServerJob('myhost.example.com',['uname -a', 'hostname', 'whoami'] username='jdoe', password='jdoe1')
r = sshread(job, tcount=0)
print(r.status, r.results)

What happens here is that you create a ServerJob object that will run three commands in succession and record the results in itself. When you call sshread you actually connect to the server and run the commands.

Working With multiple ServerJobs

To sshread multiple ServerJob objects at the same time simply create a list of them and feed that list to the sshread method. The sshread method will return a list of the completed ServerJob objects for you to then parse as needed.

from sshreader import ServerJob, sshread
jobs = list()
for host in ['myhost1.example.com', 'myhost2.example.com', 'myhost3.example.com']:
    job = ServerJob(host,['uname -a', 'hostname', 'whoami'] username='jdoe', password='jdoe1')
    jobs.append(job)
finished = sshread(jobs, tcount=0)
for job in finished:
    job.output()

Now you are ready to sshread all your servers as fast as possible!

Working With Hooks

Sometimes you want to run bits of code before or after a ServerJob executes as part of the sshread method. Sshreader provides a way to do this through Hook objects. Hook objects are simply a wrapper for a function you have defined that will run before or after a ServerJob executes. They will contain the ServerJob object itself as one of the arguments so it is easy to write a Hook that can look at or react to the status of the ServerJob.

Creating a Hook is as is as simple as:

from sshreader import ServerJob, sshread, Hook

def print_name(job):
    # You will need to ensure you accept at least one arg since
    # the ServerJob will be passed to your hook
    print('Entering hook')
    print(job.name)
    print('Leaving hook')


# Create the function as a hook object
myhook = Hook(target=print_name)
# Create a ServerJob with a prehook
job = ServerJob('myhost.example.com',['uname -a', 'hostname', 'whoami'], username='jdoe', password='jdoe1',
                prehook=myhook)
# Now, run the job
sshread(job, tcount=1)

Running Shell Commands

Sometimes you don’t want to run commands via ssh but want to run them in the shell on the localhost. Sshreader provides a method for doing that as well via the shell_command method.

from sshreader import shell_command
r = shell_command('uname -a')
print(r)

Discovering Environment Variables

Sshreader includes a method that attempts to determine the currently logged in username and any ssh keys located in ~/.ssh/, including rsa and dsa keys. You can see what sshreader can discover by calling the envvars method from the ssh module.

from sshreader.ssh import envvars
print(envvars())  # Returns a NamedTuple of info sshreader was able to gather from the OS

Copying Files

Version 3.4 of sshreader introduced the sftp_put() and sfpt_get() methods into SSH objects. These methods attempt to make it easier to use OpenSSH’s SFTP protocol to copy files to and from a remote server. The cool thing about having them inside the SSH class is that you can use one object to both SFTP files and run SSH commands on a remote server.

from sshreader.ssh import SSH
with SSH('myhost.example.com', username='jdoe', password='jdoe1') as s:
    # Copy a script file from our host to the remote host and run it.
    s.sftp_put('~/secret_script.sh', '/tmp/secret_script.sh')
    s.ssh_command('/tmp/secret_script.sh')
    # Now, get the output of the script and remove all traces of it
    s.sftp_get('/tmp/secret_output.txt', '~/secret_output.txt')
    s.ssh_command('rm /tmp/secret_output.txt', 'rm /tmp/secret_output.sh')

Warning

SFTP methods are new to sshreader and isn’t a primary feature. Support for this feature will be limited.