def __iter__(self):
current_kwargs = self._op_kwargs
previous_next_token = None
next_token = dict((key, None) for key in self._input_token)
# The number of items from result_key we've seen so far.
total_items = 0
first_request = True
primary_result_key = self.result_keys[0]
starting_truncation = 0
self._inject_starting_params(current_kwargs)
while True:
response = self._make_request(current_kwargs)
parsed = self._extract_parsed_response(response)
if first_request:
# The first request is handled differently. We could
# possibly have a resume/starting token that tells us where
# to index into the retrieved page.
if self._starting_token is not None:
starting_truncation = self._handle_first_request(
parsed, primary_result_key, starting_truncation)
first_request = False
self._record_non_aggregate_key_values(parsed)
current_response = primary_result_key.search(parsed)
if current_response is None:
current_response = []
num_current_response = len(current_response)
truncate_amount = 0
if self._max_items is not None:
truncate_amount = (total_items + num_current_response) \
- self._max_items
if truncate_amount > 0:
self._truncate_response(parsed, primary_result_key,
truncate_amount, starting_truncation,
next_token)
yield response
break
else:
yield response
total_items += num_current_response
next_token = self._get_next_token(parsed)
if all(t is None for t in next_token.values()):
break
if self._max_items is not None and \
total_items == self._max_items:
# We're on a page boundary so we can set the current
# next token to be the resume token.
self.resume_token = next_token
break
if previous_next_token is not None and \
previous_next_token == next_token:
message = ("The same next token was received "
"twice: %s" % next_token)
raise PaginationError(message=message)
self._inject_token_into_kwargs(current_kwargs, next_token)
previous_next_token = next_token
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