Getting Started

Installation

pip install -U viper-infra-commander

# Or install with batteries included

pip install -U "viper-infra-commander[batteries]"

Initialization

Viper needs to initialize a SQLite DB in the present working directory (the workspace).

# (Optional) enable tab auto completion
eval "$(viper autocomplete $(basename $SHELL))"


# Initialize SQLite DB
viper init -f

Viper in Action (Basic Mode)

Define a set of hosts in csv format (json and yml are also supported) in hosts.csv:

cat > hosts.csv << EOF

EOF

Define a task in task.py:

cat > task.py << EOF

from viper import Task

def ping_command(host):
    return "ping", "-c", "1", host.ip

def ping():
    return Task(
        name="Ping once",
        command_factory=ping_command
    )

EOF

Perform the following actions:

• Run the ping task on the set of hosts in parallel with 5 workers
• Then filter only the results where the task failed
• Re-run the task on the filtered set of hosts
• Store all the results

viper hosts:from-file hosts.csv \
        | viper hosts:run-task task.ping --max-worker 5 \
        | viper results:where returncode IS_NOT 0 \
        | viper results:re-run --indent 4

The results are stored in the DB as history. To see the stdout of the final results from history:

viper results \
        | viper results:final \
        | viper results:format "{host.hostname}: {stdout}"

Export the results to a csv file:

viper results --final \
        | viper results:to-file results.csv --indent 4

Define a job using the Python API (CLI and Python API are almost similar):

cat > job.py << EOF

from viper import WhereConditions
from task import ping

def ping_and_export(hosts):
    return (
        hosts.task(ping())
        .run(max_workers=5)
        .final()
        .to_file("results.csv")
    )

EOF

Run the job using CLI:

viper hosts:from-file hosts.csv \
        | viper run job.ping_and_export \
        | viper results:format "{host.hostname}: {stdout}"

Viperfile in Action (Advanced Mode)

Define a project with custom subcommands in viperfile:

cat > viperfile.py << EOF

from viper import Hosts, Task
from viper.project import Project, arg


foo = Project(prefix="foo")


@foo.hostgroup(args=[arg("-f", "--file", default="hosts.csv")])
def allhosts(args):
    return Hosts.from_file(args.file)


def remote_exec_command(host, command):
    return (
        "ssh",
        "-i",
        host.identity_file,
        "-l",
        host.login_name,
        "-p",
        str(host.port),
        "-o",
        "StrictHostKeyChecking=no",
        "-o",
        "PubkeyAuthentication=yes",
        host.ip,
        command,
    )


@foo.job(
    args=[
        arg("command", help="command to execute"),
        arg("-w", "--workers", type=int, default=1),
    ]
)
def remote_exec(hosts, args):
    return (
        hosts.task(
            Task(
                name="Remote execute command",
                command_factory=remote_exec_command,
                timeout=5,
            ),
            args.command,
        )
        .run(max_workers=args.workers)
        .final()
    )

EOF

See the auto generated custom subcommands:

viper --help
# Will show the subcommands: "@foo:allhosts" and "@foo:remote_exec"

Run the job, export the results in a file, and format the output:

viper @foo:allhosts \
        | viper @foo:remote_exec "uname -a" --workers 5 \
        | viper results:to-file results.csv \
        | viper results:format "{task.name} [{host.hostname}]: {returncode}: {stdout}"