Feature/nat 212 213

This PR covers NAT-212 and NAT-213.

gso/services/ipam.py

@@ -574,7 +574,7 @@ def delete_host(
     host_addresses: HostAddresses = None,
     cname_aliases: Optional[list] = None,
     service_type: str = ""
-) -> Union[V4HostAddress, V6HostAddress]:
+) -> HostAddresses:
     """Delete host record and associated CNAME records.
     All arguments passed to this function must match together a host record in
     IPAM, and all CNAME records associated to it must also be passed exactly.
@@ -672,6 +672,7 @@ def validate_network(
     """Validate IPv4 or IPv6 network.
     Check if the specified network exist, and, if it does,
     check if its comment field contains gso_subscription_id.
+    Returns the network if validation successful.
     """
     assert network, "No network specified to validate."
 
@@ -682,3 +683,64 @@ def validate_network(
     assert gso_subscription_id in network_info[0]["comment"], "GSO subscription ID does not match the one in the comment field of the IPAM network."
 
     return network
+
+
+def validate_host(
+    hostname: str = "",
+    host_addresses: HostAddresses = None,
+    cname_aliases: Optional[list] = None,
+    service_type: str = ""
+) -> HostAddresses:
+    """Validate host.
+    Check if all arguments passed to this function match together a host record in
+    IPAM, and all CNAME records associated to it also match exactly.
+    Returns the host if validation successful.
+    """
+    if cname_aliases is None:
+        cname_aliases = []
+    oss = settings.load_oss_params()
+    assert oss.IPAM
+    ipam_params = oss.IPAM
+    assert ipam_params.INFOBLOX
+    infoblox_params = ipam_params.INFOBLOX
+
+    assert hostname and host_addresses, "No host specified to validate. Either hostname or host_addresses missing."
+    domain_name = getattr(ipam_params, service_type).domain_name
+    ipv4_addr = str(host_addresses.v4)
+    ipv6_addr = str(host_addresses.v6)
+    dns_view = getattr(ipam_params, service_type).dns_view
+
+    # Find host record reference
+    r = requests.get(
+        f"{wapi(infoblox_params)}/record:host",
+        params={
+            "name": (hostname + domain_name).lower(),  # hostnames are lowercase
+            "ipv4addr": ipv4_addr,
+            "ipv6addr": ipv6_addr,
+            "view": dns_view,
+        },
+        auth=HTTPBasicAuth(infoblox_params.username, infoblox_params.password),
+        verify=False,
+        timeout=REQUESTS_TIMEOUT
+    )
+    host_data = r.json()
+    assert len(host_data) == 1, "Host to validate does not exist in IPAM."
+    assert "_ref" in host_data[0], "Host to validate does not exist in IPAM."
+
+    # Find cname records reference
+    r = requests.get(
+        f"{wapi(infoblox_params)}/record:cname",
+        params={
+            "canonical": hostname + domain_name,
+            "view": dns_view,
+        },
+        auth=HTTPBasicAuth(infoblox_params.username, infoblox_params.password),
+        verify=False,
+        timeout=REQUESTS_TIMEOUT
+    )
+    cname_data = r.json()
+    provided_cnames = [item + domain_name for item in cname_aliases]
+    found_cnames = [item["name"] for item in cname_data if "name" in item]
+    assert provided_cnames == found_cnames, "Provided CNAME alias names don't match the ones poiting to hostname."
+
+    return HostAddresses