Python 3: define basestring, use bytes.decode()

.travis.yml

@@ -9,6 +9,21 @@ python:
 
 install:
   - 'pip install -r requirements.txt'
+  - pip install flake8
+
+before_script:
+  # --exit-zero means that flake8 will not stop the build
+  # 127 characters is the width of a GitHub editor
+  # E703 statement ends with a semicolon
+  # E711 comparison to None should be 'if cond is None:'
+  # E712 comparison to False should be 'if cond is False:' or 'if not cond:'
+  # E713 test for membership should be 'not in'
+  # E999 SyntaxError: invalid syntax
+  # F401 'socket' imported but unused
+  # F403 'from dronekit import *' used; unable to detect undefined names
+  # F811 redefinition of unused 'types' from line 45
+  # F821 undefined name 'xrange'
+  flake8 . --count --exit-zero --max-line-length=127 --select=E703,E711,E712,E713,E999,F401,F403,F811,F821 --statistics
 
 script:
   - 'nosetests --debug=nose,nose.importer --debug-log=nose_debug -svx dronekit.test.unit'

dronekit/__init__.py

@@ -49,6 +49,11 @@
 import collections
 from pymavlink.dialects.v10 import ardupilotmega
 
+try:
+    basestring     # Python 2
+except NameError:  # Python 3
+    basestring = (str, bytes)
+
 
 class APIException(Exception):
     """
@@ -87,7 +92,8 @@ def __init__(self, pitch, yaw, roll):
         self.roll = roll
 
     def __str__(self):
-        return "Attitude:pitch=%s,yaw=%s,roll=%s" % (self.pitch, self.yaw, self.roll)
+        fmt = '{}:pitch={pitch},yaw={yaw},roll={roll}'
+        return fmt.format(self.__class__.__name__, **vars(self))
 
 
 class LocationGlobal(object):
@@ -2734,7 +2740,7 @@ def __len__(self):
 
     def __getitem__(self, index):
         if isinstance(index, slice):
-            return [self[ii] for ii in xrange(*index.indices(len(self)))]
+            return [self[ii] for ii in range(*index.indices(len(self)))]
         elif isinstance(index, int):
             item = self._vehicle._wploader.wp(index + 1)
             if not item:
@@ -2822,7 +2828,7 @@ def connect(ip,
 
         @vehicle.on_message('STATUSTEXT')
         def listener(self, name, m):
-            status_printer(re.sub(r'(^|\n)', '>>> ', m.text.rstrip()))
+            status_printer(re.sub(r'(^|\n)', '>>> ', m.text.decode('utf-8').rstrip()))
 
     if _initialize:
         vehicle.initialize(rate=rate, heartbeat_timeout=heartbeat_timeout)

examples/simple_goto/simple_goto.py

@@ -14,26 +14,26 @@
 import time
 
 
-#Set up option parsing to get connection string
-import argparse  
+# Set up option parsing to get connection string
+import argparse
 parser = argparse.ArgumentParser(description='Commands vehicle using vehicle.simple_goto.')
-parser.add_argument('--connect', 
-                   help="Vehicle connection target string. If not specified, SITL automatically started and used.")
+parser.add_argument('--connect',
+                    help="Vehicle connection target string. If not specified, SITL automatically started and used.")
 args = parser.parse_args()
 
 connection_string = args.connect
 sitl = None
 
 
-#Start SITL if no connection string specified
+# Start SITL if no connection string specified
 if not connection_string:
     import dronekit_sitl
     sitl = dronekit_sitl.start_default()
     connection_string = sitl.connection_string()
 
 
 # Connect to the Vehicle
-print 'Connecting to vehicle on: %s' % connection_string
+print('Connecting to vehicle on: %s' % connection_string)
 vehicle = connect(connection_string, wait_ready=True)
 
 
@@ -42,62 +42,61 @@ def arm_and_takeoff(aTargetAltitude):
     Arms vehicle and fly to aTargetAltitude.
     """
 
-    print "Basic pre-arm checks"
+    print("Basic pre-arm checks")
     # Don't try to arm until autopilot is ready
     while not vehicle.is_armable:
-        print " Waiting for vehicle to initialise..."
+        print(" Waiting for vehicle to initialise...")
         time.sleep(1)
 
-
-    print "Arming motors"
+    print("Arming motors")
     # Copter should arm in GUIDED mode
     vehicle.mode = VehicleMode("GUIDED")
-    vehicle.armed = True    
+    vehicle.armed = True
 
     # Confirm vehicle armed before attempting to take off
-    while not vehicle.armed:      
-        print " Waiting for arming..."
+    while not vehicle.armed:
+        print(" Waiting for arming...")
         time.sleep(1)
 
-    print "Taking off!"
-    vehicle.simple_takeoff(aTargetAltitude) # Take off to target altitude
+    print("Taking off!")
+    vehicle.simple_takeoff(aTargetAltitude)  # Take off to target altitude
 
-    # Wait until the vehicle reaches a safe height before processing the goto (otherwise the command 
+    # Wait until the vehicle reaches a safe height before processing the goto (otherwise the command
     #  after Vehicle.simple_takeoff will execute immediately).
     while True:
-        print " Altitude: ", vehicle.location.global_relative_frame.alt 
-        #Break and return from function just below target altitude.        
-        if vehicle.location.global_relative_frame.alt>=aTargetAltitude*0.95: 
-            print "Reached target altitude"
+        print(" Altitude: ", vehicle.location.global_relative_frame.alt)
+        # Break and return from function just below target altitude.
+        if vehicle.location.global_relative_frame.alt >= aTargetAltitude*0.95:
+            print("Reached target altitude")
             break
         time.sleep(1)
 
 arm_and_takeoff(10)
 
-print "Set default/target airspeed to 3"
+print("Set default/target airspeed to 3")
 vehicle.airspeed = 3
 
-print "Going towards first point for 30 seconds ..."
+print("Going towards first point for 30 seconds ...")
 point1 = LocationGlobalRelative(-35.361354, 149.165218, 20)
 vehicle.simple_goto(point1)
 
 # sleep so we can see the change in map
 time.sleep(30)
 
-print "Going towards second point for 30 seconds (groundspeed set to 10 m/s) ..."
+print("Going towards second point for 30 seconds (groundspeed set to 10 m/s) ...")
 point2 = LocationGlobalRelative(-35.363244, 149.168801, 20)
 vehicle.simple_goto(point2, groundspeed=10)
 
 # sleep so we can see the change in map
 time.sleep(30)
 
-print "Returning to Launch"
+print("Returning to Launch")
 vehicle.mode = VehicleMode("RTL")
 
-#Close vehicle object before exiting script
-print "Close vehicle object"
+# Close vehicle object before exiting script
+print("Close vehicle object")
 vehicle.close()
 
 # Shut down simulator if it was started.
-if sitl is not None:
+if sitl:
     sitl.stop()

requirements.txt

@@ -1,4 +1,4 @@
-pymavlink==2.0.6
+pymavlink==2.0.8
 monotonic==1.2
 future==0.15.2
 nose==1.3.7