Interface names and default (#615)

Also Fix breaking change in mypy 0.900 and install missing stub package for paramiko

Author: romainx

test-requirements.txt

@@ -2,6 +2,7 @@ mock
 pytest-cov
 pytest-xdist
 paramiko
+types-paramiko
 tornado<5
 salt
 pywinrm

test/test_modules.py

@@ -677,3 +677,26 @@ def test_addr_namespace(host):
     with pytest.raises(NotImplementedError):
         # nc is not available so an error is raised
         assert not namespace_lookup.port("443").is_reachable
+
+
+@pytest.mark.parametrize(
+    "family",
+    ["inet", None],
+)
+def test_interface(host, family):
+    # exist
+    assert host.interface("eth0", family=family).exists
+    assert not host.interface("does_not_exist", family=family).exists
+    # adresses
+    addresses = host.interface.default(family).addresses
+    assert len(addresses) > 0
+    for add in addresses:
+        try:
+            ip_address(add)
+        except ValueError:
+            pytest.fail(f"{add} is not a valid IP address")
+    # names and default
+    assert "eth0" in host.interface.names()
+    default_itf = host.interface.default(family)
+    assert default_itf.name == "eth0"
+    assert default_itf.exists

testinfra/modules/interface.py

@@ -15,10 +15,20 @@
 
 
 class Interface(Module):
-    """Test network interfaces"""
+    """Test network interfaces
 
-    def __init__(self, name):
+    >>> host.interface("eth0").exists
+    True
+
+    Optionally, the protocol family to use can be enforced.
+
+    >>> host.interface("eth0", "inet6").adresses
+    ['fe80::e291:f5ff:fe98:6b8c']
+    """
+
+    def __init__(self, name, family=None):
         self.name = name
+        self.family = family
         super().__init__()
 
     @property
@@ -49,30 +59,74 @@ def get_module_class(cls, host):
             return BSDInterface
         raise NotImplementedError
 
+    @classmethod
+    def names(cls):
+        """Return the names of all the interfaces.
+
+        >>> host.interface.names()
+        ['lo', 'tunl0', 'ip6tnl0', 'eth0']
+        """
+        raise NotImplementedError
+
+    @classmethod
+    def default(cls, family=None):
+        """Return the interface used for the default route.
+
+        >>> host.interface.default()
+        <interface eth0>
+
+        Optionally, the protocol family to use can be enforced.
+
+        >>> host.interface.default("inet6")
+        None
+        """
+        raise NotImplementedError
+
 
 class LinuxInterface(Interface):
     @cached_property
     def _ip(self):
-        return self.find_command("ip")
+        ip_cmd = self.find_command("ip")
+        if self.family is not None:
+            ip_cmd = f"{ip_cmd} -f {self.family}"
+        return ip_cmd
 
     @property
     def exists(self):
-        return self.run_test("%s link show %s", self._ip, self.name).rc == 0
+        return self.run_test("{} link show %s".format(self._ip), self.name).rc == 0
 
     @property
     def speed(self):
         return int(self.check_output("cat /sys/class/net/%s/speed", self.name))
 
     @property
     def addresses(self):
-        stdout = self.check_output("%s addr show %s", self._ip, self.name)
+        stdout = self.check_output("{} addr show %s".format(self._ip), self.name)
         addrs = []
         for line in stdout.splitlines():
             splitted = [e.strip() for e in line.split(" ") if e]
             if splitted and splitted[0] in ("inet", "inet6"):
                 addrs.append(splitted[1].split("/", 1)[0])
         return addrs
 
+    @classmethod
+    def default(cls, family=None):
+        _default = cls(None, family=family)
+        out = cls.check_output("{} route ls".format(_default._ip))
+        for line in out.splitlines():
+            if "default" in line:
+                _default.name = line.strip().rsplit(" ", 1)[-1]
+        return _default
+
+    @classmethod
+    def names(cls):
+        # -o is to tell the ip command to return 1 line per interface
+        out = cls.check_output("{} -o link show".format(cls(None)._ip))
+        interfaces = []
+        for line in out.splitlines():
+            interfaces.append(line.strip().split(": ", 2)[1].split("@", 1)[0])
+        return interfaces
+
 
 class BSDInterface(Interface):
     @property