Please note that several packages are available which are pointed to in the installation documentation.

This library contains a number of useful functions and APIs that we highlight here. They are used to interact with the system and provide a number of functions to implement command line programs and shells.

The console provides convenient way to print colored messages types in the terminal, such as errors, info, and regular messages

• cloudmesh.common.console

from cloudmesh.common.console import Console

Console.error("this is an error printed in red wth prefix ERROR:")
Console.msg("this is a msg printed in black")
Console.ok("this is an ok message printed in green")

We have lots of shell commands that call linux commands, but also have a convenient execution command that returns the results in a string.

For more information we like you to inspect the source code:

• cloudmesh.common.Shell

from cloudmesh.common.Shell import Shell

shell = Shell()

print(shell.terminal_type())

# prints after the command is finished
r = shell.execute('pwd') 
print(r)

# prints while the command is executed
r = shell.live('pwd') 
print(r)

# open a new terminal and start the command ls in it (for OSX and Gnome)
shell.terminal("ls")

# an example of a build in command
shell.pip("install cloudmesh-common")

We have many such build in commands, please see the source

A convenient way to print dictionaries and lists with repeated entries as tables, csv, json, yaml. The dictionaries can even be hierarchical.

• cloudmesh.common.Printer

Let us assume we have

data = [
    {
        "name": "Gregor",
        "address": {
            "street": "Funny Lane 11",
            "city": "Cloudville"
        }
    },
    {
        "name": "Albert",
        "address": {
            "street": "Memory Lane 1901",
            "city": "Cloudnine"
        }
    }
]

Then we can print it nicely with

print(Printer.flatwrite(self.data,
                    sort_keys=["name"],
                    order=["name", "address.street", "address.city"],
                    header=["Name", "Street", "City"],
                    output="table")
          )

Other formats such as csv, json, dict are also supported.

In addition we have also printers for printing attribute lists. Please consult the source code.

• cloudmesh.common.StopWatch

A convenient way on using named timers

from cloudmesh.common.StopWatch import StopWatch
import os

watch = StopWatch()

watch.start("test")
os.sleep(1)
watch.stop("test")

print (watch["test"])

To print them, you can aslo use

Stopwatch.benchmark.print()

• cloudmesh.common.dotdict

One dimensional Dictionaries in dot format.

from cloudmesh.common.dotdict import doctict

# convert a simple dict to a dotdict
d = dotdict({"name": "Gregor"})
# Now you can say
print(d["name"])
print(d.name)

• cloudmesh.common.ssh

  • managing ssh config files
  • managing authorized keys

Very useful functions are included in util

• cloudmesh.common.util

Especially useful are

• generating passwords
• banners
• yn_choices
• path_expansion
• grep (simple line matching)
• HEADING() which without parameter identifies the name of the function and prints its name within a banner

• added support for terminals with dark background