load_credentials

load_credentials is an transform_function to add credentials to every host. The transform_function_options username and password are supportet as well as the environment variables NORNIR_USERNAME and NORNIR_PASSWORD. transform_function_options have priority.

Example

Loading inventory without load_credentials

[1]:

from nornir import InitNornir

nr = InitNornir(
    inventory={
        "plugin": "SimpleInventory",
        "options": {"host_file": "data/hosts.yaml", "group_file": "data/groups.yaml"}
    }
)

for host in nr.inventory.hosts.values():
    print(f"{host.name}\tUser:{host.username}\tPassword:{host.password}")

dev1.group_1    User:a_user     Password:a_password
dev2.group_1    User:None       Password:from_group1
dev3.group_2    User:None       Password:None
dev4.group_2    User:None       Password:from_parent_group
dev5.no_group   User:None       Password:None

Using transform_funtion_options

Set the password for all hosts using the parameter password

[2]:

from nornir import InitNornir

nr = InitNornir(
    inventory={
        "plugin": "SimpleInventory",
        "options": {"host_file": "data/hosts.yaml", "group_file": "data/groups.yaml"},
        "transform_function": "load_credentials",
        "transform_function_options": {"password": "TopSecretP4ss"}
    }
)

for host in nr.inventory.hosts.values():
    print(f"{host.name}\tUser:{host.username}\tPassword:{host.password}")

dev1.group_1    User:a_user     Password:TopSecretP4ss
dev2.group_1    User:None       Password:TopSecretP4ss
dev3.group_2    User:None       Password:TopSecretP4ss
dev4.group_2    User:None       Password:TopSecretP4ss
dev5.no_group   User:None       Password:TopSecretP4ss

Setting username and password

[3]:

from nornir import InitNornir

nr = InitNornir(
    inventory={
        "plugin": "SimpleInventory",
        "options": {"host_file": "data/hosts.yaml", "group_file": "data/groups.yaml"},
        "transform_function": "load_credentials",
        "transform_function_options": {"username": "myUser", "password": "TopSecretP4ss"}
    }
)

for host in nr.inventory.hosts.values():
    print(f"{host.name}\tUser:{host.username}\tPassword:{host.password}")

dev1.group_1    User:myUser     Password:TopSecretP4ss
dev2.group_1    User:myUser     Password:TopSecretP4ss
dev3.group_2    User:myUser     Password:TopSecretP4ss
dev4.group_2    User:myUser     Password:TopSecretP4ss
dev5.no_group   User:myUser     Password:TopSecretP4ss

Using environment variables

Set the variable NORNIR_PASSWORD

[4]:

%set_env NORNIR_PASSWORD=AnotherPassWord!

env: NORNIR_PASSWORD=AnotherPassWord!

[5]:

from nornir import InitNornir

nr = InitNornir(
    inventory={
        "plugin": "SimpleInventory",
        "options": {"host_file": "data/hosts.yaml", "group_file": "data/groups.yaml"},
        "transform_function": "load_credentials"
    }
)

for host in nr.inventory.hosts.values():
    print(f"{host.name}\tUser:{host.username}\tPassword:{host.password}")

dev1.group_1    User:a_user     Password:AnotherPassWord!
dev2.group_1    User:None       Password:AnotherPassWord!
dev3.group_2    User:None       Password:AnotherPassWord!
dev4.group_2    User:None       Password:AnotherPassWord!
dev5.no_group   User:None       Password:AnotherPassWord!

Also set the environment variable NORNIR_USERNAME

[6]:

%set_env NORNIR_USERNAME=AnotherUser

env: NORNIR_USERNAME=AnotherUser

[7]:

from nornir import InitNornir

nr = InitNornir(
    inventory={
        "plugin": "SimpleInventory",
        "options": {"host_file": "data/hosts.yaml", "group_file": "data/groups.yaml"},
        "transform_function": "load_credentials"
    }
)

for host in nr.inventory.hosts.values():
    print(f"{host.name}\tUser:{host.username}\tPassword:{host.password}")

dev1.group_1    User:AnotherUser        Password:AnotherPassWord!
dev2.group_1    User:AnotherUser        Password:AnotherPassWord!
dev3.group_2    User:AnotherUser        Password:AnotherPassWord!
dev4.group_2    User:AnotherUser        Password:AnotherPassWord!
dev5.no_group   User:AnotherUser        Password:AnotherPassWord!

The transform_function_option can overwrite the environment variables

[8]:

from nornir import InitNornir

nr = InitNornir(
    inventory={
        "plugin": "SimpleInventory",
        "options": {"host_file": "data/hosts.yaml", "group_file": "data/groups.yaml"},
        "transform_function": "load_credentials",
        "transform_function_options": {"password": "TopSecretP4ss"}
    }
)

for host in nr.inventory.hosts.values():
    print(f"{host.name}\tUser:{host.username}\tPassword:{host.password}")

dev1.group_1    User:AnotherUser        Password:TopSecretP4ss
dev2.group_1    User:AnotherUser        Password:TopSecretP4ss
dev3.group_2    User:AnotherUser        Password:TopSecretP4ss
dev4.group_2    User:AnotherUser        Password:TopSecretP4ss
dev5.no_group   User:AnotherUser        Password:TopSecretP4ss