Get the hostname of the introspected host

This will retrieve the hostname of the host being introspected, and
return it as part of the introspection data.

Change-Id: I54084251e1b0f3a40fe5ac760b2a7e45199c9fdb
Story: #2005867
Task: #33674

doc/source/admin/how_it_works.rst

@@ -117,6 +117,13 @@ fields:
     the current boot - BIOS or UEFI) and ``pxe_interface`` (interface used
     for PXE booting, if any).
 
+``hostname``
+    hostname for the system
+
+    .. note::
+        This is most likely to be set by the DHCP server. Could be localhost
+        if the DHCP server does not set it.
+
 References
 ==========
 .. [0] Enabling Drivers - https://docs.openstack.org/ironic/latest/admin/drivers/ipa.html

ironic_python_agent/hardware.py

@@ -600,6 +600,7 @@ class HardwareManager(object):
         hardware_info['bmc_v6address'] = self.get_bmc_v6address()
         hardware_info['system_vendor'] = self.get_system_vendor_info()
         hardware_info['boot'] = self.get_boot_info()
+        hardware_info['hostname'] = netutils.get_hostname()
         return hardware_info
 
     def get_clean_steps(self, node, ports):

ironic_python_agent/netutils.py

@@ -230,6 +230,13 @@ def get_mac_addr(interface_id):
         return None
 
 
+# Other options...
+# 1. import os; os.uname()[1]
+# 2. import platform; platform.node()
+def get_hostname():
+    return socket.gethostname()
+
+
 def interface_has_carrier(interface_name):
     path = '/sys/class/net/{}/carrier'.format(interface_name)
     try:

ironic_python_agent/tests/unit/test_hardware.py

@@ -1382,7 +1382,8 @@ class TestGenericHardwareManager(base.IronicAgentTest):
         self.assertEqual(3952 * 1024 * 1024, mem.total)
         self.assertIsNone(mem.physical_mb)
 
-    def test_list_hardware_info(self):
+    @mock.patch('ironic_python_agent.netutils.get_hostname', autospec=True)
+    def test_list_hardware_info(self, mocked_get_hostname):
         self.hardware.list_network_interfaces = mock.Mock()
         self.hardware.list_network_interfaces.return_value = [
             hardware.NetworkInterface('eth0', '00:0c:29:8c:11:b1'),
@@ -1413,6 +1414,8 @@ class TestGenericHardwareManager(base.IronicAgentTest):
         self.hardware.get_bmc_v6address = mock.Mock()
         self.hardware.get_system_vendor_info = mock.Mock()
 
+        mocked_get_hostname.return_value = 'mock_hostname'
+
         hardware_info = self.hardware.list_hardware_info()
         self.assertEqual(self.hardware.get_memory(), hardware_info['memory'])
         self.assertEqual(self.hardware.get_cpus(), hardware_info['cpu'])
@@ -1422,6 +1425,7 @@ class TestGenericHardwareManager(base.IronicAgentTest):
                          hardware_info['interfaces'])
         self.assertEqual(self.hardware.get_boot_info(),
                          hardware_info['boot'])
+        self.assertEqual('mock_hostname', hardware_info['hostname'])
 
     @mock.patch.object(hardware, 'list_all_block_devices', autospec=True)
     def test_list_block_devices(self, list_mock):

releasenotes/notes/add-hostname-8bbf24712b6a4919.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    Add the hostname to the introspection data. This will likely be the
+    hostname as set by the DHCP server.