def update_function_code(params={})
function_name = params.delete('FunctionName')
s3_bucket = params.delete('S3Bucket')
s3_key = params.delete('S3Key')
s3_object_ver = params.delete('S3ObjectVersion')
zip_file = params.delete('ZipFile')
update = {}
update.merge!('S3Bucket' => s3_bucket) if s3_bucket
update.merge!('S3Key' => s3_key) if s3_key
update.merge!('S3ObjectVersion' => s3_object_ver) if s3_object_ver
update.merge!('ZipFile' => zip_file) if zip_file
request({
:method => 'PUT',
:path => "/functions/#{function_name}/versions/HEAD/code",
:body => Fog::JSON.encode(update),
:parser => Fog::AWS::Parsers::Lambda::Base.new
}.merge(params))
end