utils: add hw_inventory.py

hw_inventory.py defines classes and helpers functions enabling
fetching of hardware inventory from a running client.

Uses a subprocess call to the command 'lshw -json' to obtain hardware
information.

Relevant public functions:

> get_hardware_inventory()
	Main function encapsulating subprocess and output processing
	logic.
	Returns a HardwareInventory object.

> legacy_list_hardware_inventory(inventory)
	Legacy string representation of parameter HardwareInventory object

1 files changed, 309 insertions, 0 deletions

diff --git a/src/utils/hw_inventory.py b/src/utils/hw_inventory.py
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+#
+# Copyright (C) 2023 Soleta Networks <info@soleta.eu>
+#
+# This program is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Affero General Public License as published by the
+# Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+
+import json
+import os.path
+import shlex
+import subprocess
+
+from collections import namedtuple
+from enum import Enum, auto
+
+
+SYSFS_EFI_PATH = '/sys/firmware/efi'
+
+
+class HardwareType(Enum):
+    MULTIMEDIA = 1
+    BOOTMODE = 2
+    FIRMWARE = 3
+    GRAPHICS = 4
+    STORAGE = 5
+    NETWORK = 6
+    CHASSIS = 7
+    MEMORY = 8
+    MODEL = 9
+    DISK = 10
+    CPU = 11
+    USB = 12
+    CD = 13
+
+
+class HardwareElement():
+    """
+    Simple container of a hardware type and its name
+    """
+    def __init__(self, hwtype, name):
+        self.type = hwtype
+        self.name = name
+
+    def __str__(self):
+        return f'Hardware element {self.type}: {self.name}'
+
+
+class HardwareInventory():
+    """
+    Collection of hardware elements
+    """
+    def __init__(self):
+        self.elements = list()
+
+    def add_element(self, elem):
+        if elem.type not in HardwareType:
+            raise ValueError('Unsupported hardware type')
+        if not elem.name:
+            raise ValueError('Empty hardware element name')
+        self.elements.append(elem)
+
+
+def _bytes_to_human(size):
+    suffixes = ['B', 'MiB', 'GiB', 'TiB']
+    if type(size) is not int:
+        raise TypeError('Invalid type')
+    for exponent, suffix in enumerate(suffixes, start=1):
+        conv = size / (1024**exponent)
+        if conv < 1024:
+            return f'{conv:.2f} {suffix}'
+
+# Utility methods for lshw json output processing
+
+def _fill_computer_model(inventory, root):
+    model = ' '.join([root['vendor'], root['product'], root['version']])
+    elem = HardwareElement(HardwareType.MODEL, model)
+    inventory.add_element(elem)
+
+
+def _fill_chassis_type(inventory, root):
+    chassis = root['configuration']['chassis']
+    elem = HardwareElement(HardwareType.CHASSIS, chassis)
+    inventory.add_element(elem)
+
+
+def _fill_bootmode(inventory):
+    bootmode = 'UEFI' if os.path.exists(SYSFS_EFI_PATH) else 'BIOS'
+    elem = HardwareElement(HardwareType.BOOTMODE, bootmode)
+    inventory.add_element(elem)
+
+
+def _process_core_firmware(inventory, obj):
+    desc = ' '.join([obj['description'], obj['vendor'], obj['version']])
+    firmware_elem = HardwareElement(HardwareType.FIRMWARE, desc)
+    inventory.add_element(firmware_elem)
+
+
+def _process_core_cpu(inventory, obj):
+    cpu = obj['product']
+    cpu_elem = HardwareElement(HardwareType.CPU, cpu)
+    inventory.add_element(cpu_elem)
+
+
+def _process_core_mem_bank(inventory, obj):
+    slot = obj.get('slot', 'Unknown slot')
+    size = _bytes_to_human(obj['size']) if 'size' in obj else None
+    if size:
+        mem = ' '.join([obj['vendor'], obj['product'], size, f'({slot})'])
+        mem_elem = HardwareElement(HardwareType.MEMORY, mem)
+        inventory.add_element(mem_elem)
+
+
+def _process_core_mem(inventory, obj):
+    banks = obj['children']
+    for bank in banks:
+        _process_core_mem_bank(inventory, bank)
+
+
+def _process_core_pci_usb(inventory, obj):
+    name = ' '.join([obj['vendor'], obj['product']])
+    usb_elem = HardwareElement(HardwareType.USB, name)
+    inventory.add_element(usb_elem)
+
+
+def _process_core_pci_display(inventory, obj):
+    name = ' '.join([obj['vendor'], obj['product']])
+    display_elem = HardwareElement(HardwareType.GRAPHICS, name)
+    inventory.add_element(display_elem)
+
+
+def _process_core_pci_network(inventory, obj):
+    link = obj.get('size', 'Unknown link speed')
+    if type(link) == int:
+        if link >= 1000000000:
+            linkh = f'{link/1e9} Gbit/s'
+        else:
+            linkh = f'{link/1e6} Mbit/s'
+    name = ' '.join([obj['vendor'], obj['product'], f'({linkh})'])
+    elem = HardwareElement(HardwareType.NETWORK, name)
+    inventory.add_element(elem)
+
+
+def _process_core_pci_storage_child(inventory, obj):
+    obj_id = obj['id']
+    if obj_id.startswith('disk') or obj_id.startswith('nvme'):
+        size = bytes_to_human(obj['size']) if 'size' in obj else 'Unknown size'
+        name = ' '.join([obj['description'], obj['product'], size])
+        elem = HardwareElement(HardwareType.DISK, name)
+        inventory.add_element(elem)
+
+
+def _process_core_pci_storage(inventory, obj):
+    name = ' '.join([obj['vendor'], obj['product']])
+    elem = HardwareElement(HardwareType.STORAGE, name)
+    inventory.add_element(elem)
+    # Disks follow a storage section
+    for storage_child in obj.get('children', []):
+        _process_core_pci_storage_child(inventory, storage_child)
+
+
+def _process_core_pci_disk(inventory, obj):
+    name = ' '.join([obj['vendor'], obj['product']])
+    elem = HardwareElement(HardwareType.DISK, name)
+    inventory.add_element(elem)
+
+
+def _process_core_pci_multimedia(inventory, obj):
+    name = ' '.join([obj['vendor'], obj['product']])
+    elem = HardwareElement(HardwareType.MULTIMEDIA, name)
+    inventory.add_element(elem)
+
+
+def _process_core_pci_child(inventory, obj):
+    obj_id = obj['id']
+    if obj_id.startswith('usb'):
+        _process_core_pci_usb(inventory, obj)
+    elif obj_id.startswith('display'):
+        _process_core_pci_display(inventory, obj)
+    elif obj_id.startswith('network'):
+        _process_core_pci_network(inventory, obj)
+    elif obj_id.startswith('sata') or obj_id.startswith('storage'):
+        _process_core_pci_storage(inventory, obj)
+    elif obj_id.startswith('multimedia'):
+        _process_core_pci_multimedia(inventory, obj)
+    elif obj_id.startswith('pci'):  # PCI bridge
+        bridge_children = obj.get('children', [])
+        for bridge_child in bridge_children:
+            _process_core_pci_child(inventory, bridge_child)
+
+
+def _process_core_pci(inventory, obj):
+    children = obj.get('children', [])
+    for child in children:
+        _process_core_pci_child(inventory, child)
+
+
+def _process_core_scsi_disk(inventory, obj):
+    vendor = obj.get('vendor', 'Unknown vendor')
+    name = ' '.join([vendor, obj['product']])
+    elem = HardwareElement(HardwareType.DISK, name)
+    inventory.add_element(elem)
+
+
+def _process_core_scsi_cdrom(inventory, obj):
+    name = ' '.join([obj['vendor'], obj['product']])
+    elem = HardwareElement(HardwareType.CD, name)
+    inventory.add_element(elem)
+
+
+def _process_core_scsi_child(inventory, obj):
+    obj_id = obj['id']
+    if obj_id.startswith('disk'):
+        _process_core_scsi_disk(inventory, obj)
+    elif obj_id.startswith('cdrom'):
+        _process_core_scsi_cdrom(inventory, obj)
+
+
+def _process_core_scsi(inventory, obj):
+    children = obj['children']
+    for child in children:
+        _process_core_scsi_child(inventory, child)
+
+def _process_core(inventory, core):
+    for element in core['children']:
+        element_id = element['id']
+        if element_id.startswith('firmware'):
+            _process_core_firmware(inventory, element)
+        elif element_id.startswith('cpu'):
+            _process_core_cpu(inventory, element)
+        elif element_id.startswith('memory'):
+            _process_core_mem(inventory, element)
+        elif element_id.startswith('pci'):
+            _process_core_pci(inventory, element)
+        elif element_id.startswith('scsi'):
+            _process_core_scsi(inventory, element)
+
+def legacy_hardware_element(element):
+    """
+    Legacy string representation of a hardware element.
+
+    For example, a graphics card named "Foo" would be
+    represented as "vga=Foo"
+    """
+    if type(element) is not HardwareElement:
+        raise TypeError('Invalid type')
+    elif element.type is HardwareType.MULTIMEDIA:
+        nemonic = 'mul'
+    elif element.type is HardwareType.BOOTMODE:
+        nemonic = 'boo'
+    elif element.type is HardwareType.FIRMWARE:
+        nemonic = 'bio'
+    elif element.type is HardwareType.GRAPHICS:
+        nemonic = 'vga'
+    elif element.type is HardwareType.CHASSIS:
+        nemonic = 'cha'
+    elif element.type is HardwareType.STORAGE:
+        nemonic = 'sto'
+    elif element.type is HardwareType.NETWORK:
+        nemonic = 'net'
+    elif element.type is HardwareType.MEMORY:
+        nemonic = 'mem'
+    elif element.type is HardwareType.MODEL:
+        nemonic = 'mod'
+    elif element.type is HardwareType.DISK:
+        nemonic = 'dis'
+    elif element.type is HardwareType.CPU:
+        nemonic = 'cpu'
+    elif element.type is HardwareType.USB:
+        nemonic = 'usb'
+    elif element.type is HardwareType.CD:
+        nemonic = 'cdr'
+    return f'{nemonic}={element.name}'
+
+def legacy_list_hardware_inventory(inventory):
+    """
+    Return a hardware inventory as a legacy string.  Map each hardware
+    component to its legacy string representation and concatenate using a new
+    line.
+
+    This is the same output as legacy script ogListHardware.
+    """
+    return '\n'.join([legacy_hardware_element(elem) for elem in inventory.elements])
+
+
+def get_hardware_inventory():
+    proc = subprocess.run(['lshw', '-json'], stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)
+    j = json.loads(proc.stdout)
+
+    if type(j) is list:
+        root = j[0]
+    if type(root) is not dict:
+        raise ValueError('Unvalid lshw json output')
+
+    inventory = HardwareInventory()
+    _fill_computer_model(inventory, root)
+    _fill_chassis_type(inventory, root)
+    _fill_bootmode(inventory)
+    # Process 'children' node
+    # Usually there are two type of children from lshw json root:
+    # 'core' and 'power'.
+    # We are only interested in 'core'.
+    children = root['children']
+    for child in children:
+        child_id = child['id']
+        if child_id == 'core':
+            _process_core(inventory, child)
+
+    return inventory