Added network utility `network.fetch_host_ip` to fetch IP by hostname

CHANGELOG.md

@@ -16,6 +16,8 @@
    * `get_object_function` should contain the Python path to a function that takes a request object and returns an object matching the ActivityPub ID for the request or `None`.
    * `process_payload_function` should contain the Python path to a function that takes in a request object. It should return `True` if successful (or placed in queue for processing later) or `False` in case of any errors.
 
+* Added network utility `network.fetch_host_ip` to fetch IP by hostname.
+
 ### Changed
 
 * **Backwards incompatible.** Lowest compatible Python version is now 3.6.

federation/tests/utils/test_network.py

@@ -5,7 +5,7 @@ from requests import HTTPError
 from requests.exceptions import SSLError, RequestException
 
 from federation.utils.network import (
-    fetch_document, USER_AGENT, send_document, fetch_country_by_ip, fetch_host_ip_and_country)
+    fetch_document, USER_AGENT, send_document, fetch_country_by_ip, fetch_host_ip_and_country, fetch_host_ip)
 
 
 @patch('federation.utils.network.ipdata', autospec=True)
@@ -98,10 +98,18 @@ class TestFetchDocument:
         assert exc.__class__ == RequestException
 
 
-class TestHostIpAndCountry:
+class TestFetchHostIp:
     @patch('federation.utils.network.socket.gethostbyname', autospec=True, return_value='127.0.0.1')
+    def test_calls(self, mock_get_ip):
+        result = fetch_host_ip('domain.local')
+        assert result == '127.0.0.1'
+        mock_get_ip.assert_called_once_with('domain.local')
+
+
+class TestFetchHostIpAndCountry:
     @patch('federation.utils.network.fetch_country_by_ip', autospec=True, return_value='FI')
-    def test_calls(self, mock_fetch_country, mock_get_ip):
+    @patch('federation.utils.network.fetch_host_ip', autospec=True, return_value='127.0.0.1')
+    def test_calls(self, mock_get_ip, mock_fetch_country):
         result = fetch_host_ip_and_country('domain.local')
         assert result == ('127.0.0.1', 'FI')
         mock_get_ip.assert_called_once_with('domain.local')

federation/utils/network.py

@@ -1,5 +1,6 @@
 import logging
 import socket
+from typing import Tuple
 
 import requests
 from ipdata import ipdata
@@ -95,13 +96,24 @@ def fetch_document(url=None, host=None, path="/", timeout=10, raise_ssl_errors=T
         return None, None, ex
 
 
-def fetch_host_ip_and_country(host):
+def fetch_host_ip(host: str) -> str:
     """
-    Fetch ip and country by host
+    Fetch ip by host
     """
     try:
         ip = socket.gethostbyname(host)
     except socket.gaierror:
+        return ''
+
+    return ip
+
+
+def fetch_host_ip_and_country(host: str) -> Tuple:
+    """
+    Fetch ip and country by host
+    """
+    ip = fetch_host_ip(host)
+    if not host:
         return '', ''
 
     country = fetch_country_by_ip(ip)