Added logging and VidStab calls

- Added logging calls instead of print statements.
- Added the code to call VidStab to stabilize the video
- Still need to pipe stuff together so `in_path` and `out_path` actually
  exist.

stabVideo/lambda_function.py

@@ -5,6 +5,11 @@
 
 import os
 
+import logging
+
+logger = logging.getLogger(__name__)
+logger.setLevel(logging.WARNING)
+
 OUTPUT_BUCKET = str(os.getenv('OUTPUT_BUCKET'))
 KP_METHOD = str(os.getenv('KP_METHOD'))
 BORDER_TYPE = str(os.getenv('BORDER_TYPE'))
@@ -18,11 +23,16 @@
 
 def download_file(bucket, key):
     name = get_tmp_file_from_key(key)
+    logger.info("Downloading s3://{}/{} to {}".format(bucket, key, name))
     s3.download_file(bucket, key, name)
+    logger.info("Downloaded video file to {}".format(name))
     return name
 
 def upload_file(bucket, key, local_path):
+    logger.info("Uploading {} to s3://{}/{}".format(local_path, bucket, key))
     response = s3.upload_file(local_path, bucket, key)
+    logger.info("Uploaded {} to s3://{}/{}".format(local_path, bucket, key))
+    logger.debug(response)
     return response
 
 # --------------- Other Helper Functions --------
@@ -35,26 +45,51 @@ def get_tmp_file_from_key(key):
 
 # --------------- Main handler ------------------
 
+VIDSTAB_ERROR = None
+
+try:
+    from vidstab import VidStab
+except ImportError as e:
+    logger.critical("Could not import VidStab")
+    VIDSTAB_ERROR = e
+
 def lambda_handler(event, context):
     bucket = event['Records'][0]['s3']['bucket']['name']
     key = urllib.unquote_plus(event['Records'][0]['s3']['object']['key'].encode('utf8'))
 
+    if VIDSTAB_ERROR is not None:
+        raise VIDSTAB_ERROR
+
     try:
 
         head_response = s3.head_object(Bucket=bucket, Key=key)
         size = head_response['ContentLength']
+        content_type = head_response['ContentType']
         if size <= MAX_SIZE:
             # Do the stabilization
-            pass
+            if content_type[0:5] == "video":
+                stabilizer = VidStab(kp_method=KP_METHOD)
+                if BORDER_TYPE == "black":
+                    stabilizer.stabilize(input_path=in_path,
+                                         output_path=out_path,
+                                         border_type=BORDER_TYPE,
+                                         border_size=BORDER_SIZE)
+                else:
+                    stabilizer.stabilize(input_path=in_path,
+                                         output_path=out_path,
+                                         border_type=BORDER_TYPE)
+
+            else:
+                raise IOError("Object {} from bucket {} ".format(key, bucket) +
+                              "is not a video.")
         else:
-            raise IOError("Object {} from bucket {}".format(key, bucket) +
+            raise IOError("Object {} from bucket {} ".format(key, bucket) +
                           "exceeds max allowable size for stabilization.")
 
     except IOError as e:
-        print(e)
+        logger.exception("IOError occurred during lambda handling")
         raise e
     except Exception as e:
-        print(e)
-        print("Error processing object {} from bucket {}. ".format(key, bucket) +
-              "Make sure your object and bucket exist and your bucket is in the same region as this function.")
+        logger.exception("Error processing object {} from bucket {}. ".format(key, bucket) +
+                         "Make sure your object and bucket exist and your bucket is in the same region as this function.")
         raise e