import boto3
import time
import sys

print ("S3 Listing at %s" % time.ctime())
s3 = boto3.client('s3');

def listObjectsInbucket( bucketName ):
  "Displays the contents of a single bucket"
  if ( len(bucketName) == 0 ):
    print ("bucket name not provided, listing all buckets....")
    time.sleep(8)
  else:
    print ("Bucket Name provided is: %s" % bucketName)
    s3bucket = boto3.resource('s3')
    my_bucket = s3bucket.Bucket(bucketName)
    for object in my_bucket.objects.all():
      print(object.key)
  return

def listAllBuckets():
  "Displays the contents of S3 for the current account"
  try:
    # Call S3 to list current buckets
    response = s3.list_buckets()
    for bucket in response['Buckets']:
      print (bucket['Name'])
  except ClientError as e:
    print("The bucket does not exist, choose how to deal with it or raise the exception: "+e)
  return

def downloadObjectAsFile(BUCKET_NAME,object_key,filename):
    """
    Bucket name in the s3 bucket
    object_key ; path of the file in the bucket barring bucket name
    filename : the path of the downloaded file
    """
    try:
        s3.Bucket(BUCKET_NAME).download_file(object_key, filename)
    except botocore.exceptions.ClientError as e:
        if e.response['Error']['Code'] == "404":
            print("The object does not exist.")
        else:
            raise

def uploadFileAsObject(BUCKET_NAME,object_key,filename):
    """
    Bucket name in the s3 bucket
    object_key ; path of the file in the bucket barring bucket name
    filename : the path of the downloaded file
    """
    try:
        s3.Bucket(BUCKET_NAME).upload_file(filename, object_key)
    except botocore.exceptions.ClientError as e:
        if e.response['Error']['Code'] == "404":
            print("The object is not created.")
        else:
            raise

if __name__=='__main__':
  if ( len(sys.argv[1:]) != 0 ):
    showSingleBucket(''.join(sys.argv[1]))
  else:
    showAllBuckets()