backlight module

Probably I'll discard these as soon as I come up with a nice
generic way of reading multiple files, converting values etc.

README.md

@@ -35,6 +35,18 @@ as you like.
 ## Modules
 
 
+### backlight
+
+
+Shows backlight brightness
+
+
+* format — format string used for output. {brightness}, {max_brightness}, {percentage} are available (default: {brightness}/{max_brightness})
+* backlight — backlight. See /sys/class/backlight/ (default: acpi_video0)
+* color —  (default: #FFFFFF)
+
+
+
 ### battery
 
 
@@ -43,6 +55,7 @@ battery status
 
 
 * battery_ident —  (default: BAT0)
+* format —  (default: {status} {remaining})
 
 
 
@@ -79,6 +92,7 @@ The `backends` setting determines the backends to use. Currently available are:
 * color_unread —  (default: #ff0000)
 * format —  (default: {unread} new email)
 * format_plural —  (default: {unread} new emails)
+* hide_if_null — Don't output anything if there are no new mails (default: True)
 
 
     Currently available backends are:

i3pystatus/backlight.py

@@ -0,0 +1,31 @@
+from i3pystatus import IntervalModule
+
+class Backlight(IntervalModule):
+    """
+    Shows backlight brightness
+    """
+
+    settings = (
+        ("format", "format string used for output. {brightness}, {max_brightness}, {percentage} are available"),
+        ("backlight", "backlight. See /sys/class/backlight/"),
+        "color",
+    )
+    format = "{brightness}/{max_brightness}"
+    color = "#FFFFFF"
+    backlight = "acpi_video0"
+
+    def init(self):
+        self.base_path = "/sys/class/backlight/{backlight}".format(backlight=self.backlight)
+  
+        with open("{base_path}/max_brightness".format(base_path=self.base_path), "r") as f:
+            self.max_brightness = int(f.read())
+
+    def run(self):
+        with open("{base_path}/brightness".format(base_path=self.base_path), "r") as f:
+            brightness = int(f.read())
+
+        percentage = (brightness / self.max_brightness) * 100
+        self.output = {
+            "full_text" : self.format.format(brightness=brightness, max_brightness=self.max_brightness, percentage=percentage),
+            "color": self.color,
+        }

i3pystatus/mail/__init__.py

@@ -23,7 +23,8 @@ class Mail(IntervalModule):
 
     settings = (
         ("backends", "List of backends (instances of i3pystatus.mail.xxx)"),
-        "color", "color_unread", "format", "format_plural"
+        "color", "color_unread", "format", "format_plural",
+        ("hide_if_null", "Don't output anything if there are no new mails"),
     )
     required = ("backends",)
 
@@ -31,6 +32,7 @@ class Mail(IntervalModule):
     color_unread  ="#ff0000"
     format = "{unread} new email"
     format_plural = "{unread} new emails"
+    hide_if_null = True
 
     def init(self):
         for backend in self.backends:
@@ -42,6 +44,9 @@ class Mail(IntervalModule):
         if not unread:
             color = self.color
             urgent = "false"
+            if self.hide_if_null:
+                self.output = None
+                return
         else:
             color = self.color_unread
             urgent = "true"