Add arista_eos_ssh driver for Arista EOS over SSH

changes/418.added

@@ -0,0 +1 @@
+Added the `arista_eos_ssh` device type, an SSH-only Arista EOS driver for environments where eAPI is not enabled; it exposes the same API as `arista_eos_eapi` and obtains structured data via the CLI's `| json` pipe.

docs/user/lib_getting_started.md

@@ -11,16 +11,19 @@ The first way is to use the `ntc_device` object. Just pass in all required param
 
 Like many libraries, we need to pass in the host/IP and credentials.  Because this is a multi-vendor/API library, we also use the `device_type` parameter to identify which device we are building an instance of.
 
-pyntc currently supports seven device types:
+pyntc currently supports the following device types:
 
 - cisco_aireos_ssh
 - cisco_asa_ssh
 - cisco_ios_ssh
 - cisco_nxos_nxapi
 - arista_eos_eapi
+- arista_eos_ssh
 - juniper_junos_netconf
 - f5_tmos_icontrol
 
+Arista EOS is supported over two transports. `arista_eos_eapi` uses eAPI (JSON-RPC over HTTP/HTTPS) and requires `management api http-commands` to be enabled on the device. `arista_eos_ssh` uses SSH only, for environments where eAPI is not available; it exposes exactly the same methods and properties as the eAPI driver, so the two are interchangeable.
+
 The example below shows how to build a device object when working with a Cisco IOS router.
 
 ```python

mkdocs.yml

@@ -162,6 +162,7 @@ nav:
           - pyntc.devices.asa_device: "code-reference/pyntc/devices/asa_device.md"
           - pyntc.devices.base_device: "code-reference/pyntc/devices/base_device.md"
           - pyntc.devices.eos_device: "code-reference/pyntc/devices/eos_device.md"
+          - pyntc.devices.eos_ssh_device: "code-reference/pyntc/devices/eos_ssh_device.md"
           - pyntc.devices.f5_device: "code-reference/pyntc/devices/f5_device.md"
           - pyntc.devices.ios_device: "code-reference/pyntc/devices/ios_device.md"
           - pyntc.devices.iosxewlc_device: "code-reference/pyntc/devices/iosxewlc_device.md"

pyntc/devices/__init__.py

@@ -3,6 +3,7 @@
 from .aireos_device import AIREOSDevice
 from .asa_device import ASADevice
 from .eos_device import EOSDevice
+from .eos_ssh_device import EOSSSHDevice
 from .f5_device import F5Device
 from .ios_device import IOSDevice
 from .iosxewlc_device import IOSXEWLCDevice
@@ -13,6 +14,7 @@
 supported_devices = {
     "cisco_asa_ssh": ASADevice,
     "arista_eos_eapi": EOSDevice,
+    "arista_eos_ssh": EOSSSHDevice,
     "f5_tmos_icontrol": F5Device,
     "cisco_ios_ssh": IOSDevice,
     "cisco_iosxr_ssh": IOSXRDevice,