Add util functions to extract network interfaces and gateway

src/yunohost/monitor.py

@@ -164,6 +164,7 @@ def monitor_network(units=None, human_readable=False):
         units = ['check', 'usage', 'infos']
 
     # Get network devices and their addresses
+    # TODO / FIXME : use functions in utils/network.py to manage this
     devices = {}
     output = subprocess.check_output('ip addr show'.split())
     for d in re.split('^(?:[0-9]+: )', output, flags=re.MULTILINE):
@@ -213,6 +214,7 @@ def monitor_network(units=None, human_readable=False):
         elif u == 'infos':
             p_ipv4 = get_public_ip() or 'unknown'
 
+            # TODO / FIXME : use functions in utils/network.py to manage this
             l_ip = 'unknown'
             for name, addrs in devices.items():
                 if name == 'lo':

src/yunohost/utils/network.py

@@ -19,10 +19,13 @@
 
 """
 import logging
+import re
+import subprocess
 from urllib import urlopen
 
 logger = logging.getLogger('yunohost.utils.network')
 
+
 def get_public_ip(protocol=4):
     """Retrieve the public IP address from ip.yunohost.org"""
 
@@ -37,3 +40,76 @@ def get_public_ip(protocol=4):
         return urlopen(url).read().strip()
     except IOError:
         return None
+
+
+def get_network_interfaces():
+
+    # Get network devices and their addresses (raw infos from 'ip addr')
+    devices_raw = {}
+    output = subprocess.check_output('ip addr show'.split())
+    for d in re.split('^(?:[0-9]+: )', output, flags=re.MULTILINE):
+        # Extract device name (1) and its addresses (2)
+        m = re.match('([^\s@]+)(?:@[\S]+)?: (.*)', d, flags=re.DOTALL)
+        if m:
+            devices_raw[m.group(1)] = m.group(2)
+
+    # Parse relevant informations for each of them
+    devices = {name: _extract_inet(addrs) for name, addrs in devices_raw.items() if name != "lo"}
+
+    return devices or "unknown"
+
+
+def get_gateway():
+
+    output = subprocess.check_output('ip route show'.split())
+    m = re.search('default via (.*) dev ([a-z]+[0-9]?)', output)
+    if not m:
+        return "unknown"
+
+    addr = _extract_inet(m.group(1), True)
+    return addr.popitem()[1] if len(addr) == 1 else "unknown"
+
+
+###############################################################################
+
+
+def _extract_inet(string, skip_netmask=False, skip_loopback=True):
+    """
+    Extract IP addresses (v4 and/or v6) from a string limited to one
+    address by protocol
+
+    Keyword argument:
+        string -- String to search in
+        skip_netmask -- True to skip subnet mask extraction
+        skip_loopback -- False to include addresses reserved for the
+            loopback interface
+
+    Returns:
+        A dict of {protocol: address} with protocol one of 'ipv4' or 'ipv6'
+
+    """
+    ip4_pattern = '((25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}'
+    ip6_pattern = '(((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)::((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)'
+    ip4_pattern += '/[0-9]{1,2})' if not skip_netmask else ')'
+    ip6_pattern += '/[0-9]{1,3})' if not skip_netmask else ')'
+    result = {}
+
+    for m in re.finditer(ip4_pattern, string):
+        addr = m.group(1)
+        if skip_loopback and addr.startswith('127.'):
+            continue
+
+        # Limit to only one result
+        result['ipv4'] = addr
+        break
+
+    for m in re.finditer(ip6_pattern, string):
+        addr = m.group(1)
+        if skip_loopback and addr == '::1':
+            continue
+
+        # Limit to only one result
+        result['ipv6'] = addr
+        break
+
+    return result