Merge pull request #363 from ncoop/iss357

Create updates backend for dnf

i3pystatus/updates/dnf.py

@@ -0,0 +1,25 @@
+from i3pystatus.core.command import run_through_shell
+from i3pystatus.updates import Backend
+from re import split
+
+
+class Dnf(Backend):
+    """
+    Gets update count for RPM-based distributions with dnf.
+
+    https://dnf.readthedocs.org/en/latest/command_ref.html#check-update-command
+    """
+
+    @property
+    def updates(self):
+        command = ["dnf", "check-update"]
+        dnf = run_through_shell(command)
+
+        update_count = 0
+        if dnf.rc == 100:
+            lines = dnf.out.splitlines()[2:]
+            lines = [l for l in lines if len(split("\s{2,}", l.rstrip())) == 3]
+            update_count = len(lines)
+        return update_count
+
+Backend = Dnf