import tempfile import pytest import queuelib from scrapy.http.request import Request from scrapy.pqueues import DownloaderAwarePriorityQueue, ScrapyPriorityQueue from scrapy.spiders import Spider from scrapy.squeues import FifoMemoryQueue from scrapy.utils.misc import build_from_crawler, load_object from scrapy.utils.test import get_crawler from tests.test_scheduler import MockDownloader, MockEngine class TestPriorityQueue: def setup_method(self): self.crawler = get_crawler(Spider) self.spider = self.crawler._create_spider("foo") def test_queue_push_pop_one(self): temp_dir = tempfile.mkdtemp() queue = ScrapyPriorityQueue.from_crawler( self.crawler, FifoMemoryQueue, temp_dir ) assert queue.pop() is None assert len(queue) == 0 req1 = Request("https://example.org/1", priority=1) queue.push(req1) assert len(queue) == 1 dequeued = queue.pop() assert len(queue) == 0 assert dequeued.url == req1.url assert dequeued.priority == req1.priority assert not queue.close() def test_no_peek_raises(self): if hasattr(queuelib.queue.FifoMemoryQueue, "peek"): pytest.skip("queuelib.queue.FifoMemoryQueue.peek is defined") temp_dir = tempfile.mkdtemp() queue = ScrapyPriorityQueue.from_crawler( self.crawler, FifoMemoryQueue, temp_dir ) queue.push(Request("https://example.org")) with pytest.raises( NotImplementedError, match="The underlying queue class does not implement 'peek'", ): queue.peek() queue.close() def test_peek(self): if not hasattr(queuelib.queue.FifoMemoryQueue, "peek"): pytest.skip("queuelib.queue.FifoMemoryQueue.peek is undefined") temp_dir = tempfile.mkdtemp() queue = ScrapyPriorityQueue.from_crawler( self.crawler, FifoMemoryQueue, temp_dir ) assert len(queue) == 0 assert queue.peek() is None req1 = Request("https://example.org/1") req2 = Request("https://example.org/2") req3 = Request("https://example.org/3") queue.push(req1) queue.push(req2) queue.push(req3) assert len(queue) == 3 assert queue.peek().url == req1.url assert queue.pop().url == req1.url assert len(queue) == 2 assert queue.peek().url == req2.url assert queue.pop().url == req2.url assert len(queue) == 1 assert queue.peek().url == req3.url assert queue.pop().url == req3.url assert not queue.close() def test_queue_push_pop_priorities(self): temp_dir = tempfile.mkdtemp() queue = ScrapyPriorityQueue.from_crawler( self.crawler, FifoMemoryQueue, temp_dir, [-1, -2, -3] ) assert queue.pop() is None assert len(queue) == 0 req1 = Request("https://example.org/1", priority=1) req2 = Request("https://example.org/2", priority=2) req3 = Request("https://example.org/3", priority=3) queue.push(req1) queue.push(req2) queue.push(req3) assert len(queue) == 3 dequeued = queue.pop() assert len(queue) == 2 assert dequeued.url == req3.url assert dequeued.priority == req3.priority assert queue.close() == [-1, -2] class TestDownloaderAwarePriorityQueue: def setup_method(self): crawler = get_crawler(Spider) crawler.engine = MockEngine(downloader=MockDownloader()) self.queue = DownloaderAwarePriorityQueue.from_crawler( crawler=crawler, downstream_queue_cls=FifoMemoryQueue, key="foo/bar", ) def teardown_method(self): self.queue.close() def test_push_pop(self): assert len(self.queue) == 0 assert self.queue.pop() is None req1 = Request("http://www.example.com/1") req2 = Request("http://www.example.com/2") req3 = Request("http://www.example.com/3") self.queue.push(req1) self.queue.push(req2) self.queue.push(req3) assert len(self.queue) == 3 assert self.queue.pop().url == req1.url assert len(self.queue) == 2 assert self.queue.pop().url == req2.url assert len(self.queue) == 1 assert self.queue.pop().url == req3.url assert len(self.queue) == 0 assert self.queue.pop() is None def test_no_peek_raises(self): if hasattr(queuelib.queue.FifoMemoryQueue, "peek"): pytest.skip("queuelib.queue.FifoMemoryQueue.peek is defined") self.queue.push(Request("https://example.org")) with pytest.raises( NotImplementedError, match="The underlying queue class does not implement 'peek'", ): self.queue.peek() def test_peek(self): if not hasattr(queuelib.queue.FifoMemoryQueue, "peek"): pytest.skip("queuelib.queue.FifoMemoryQueue.peek is undefined") assert len(self.queue) == 0 req1 = Request("https://example.org/1") req2 = Request("https://example.org/2") req3 = Request("https://example.org/3") self.queue.push(req1) self.queue.push(req2) self.queue.push(req3) assert len(self.queue) == 3 assert self.queue.peek().url == req1.url assert self.queue.pop().url == req1.url assert len(self.queue) == 2 assert self.queue.peek().url == req2.url assert self.queue.pop().url == req2.url assert len(self.queue) == 1 assert self.queue.peek().url == req3.url assert self.queue.pop().url == req3.url assert self.queue.peek() is None @pytest.mark.parametrize( ("input", "output"), [ # By default, start requests are FIFO, other requests are LIFO. ([{}, {}], [2, 1]), ([{"start": True}, {"start": True}], [1, 2]), # Priority matters. ([{"priority": 1}, {"start": True}], [1, 2]), ([{}, {"start": True, "priority": 1}], [2, 1]), # For the same priority, start requests pop last. ([{}, {"start": True}], [1, 2]), ([{"start": True}, {}], [2, 1]), ], ) def test_pop_order(input, output): def make_url(index): return f"https://toscrape.com/{index}" def make_request(index, data): meta = {} if data.get("start", False): meta["is_start_request"] = True return Request( url=make_url(index), priority=data.get("priority", 0), meta=meta, ) input_requests = [ make_request(index, data) for index, data in enumerate(input, start=1) ] expected_output_urls = [make_url(index) for index in output] crawler = get_crawler(Spider) settings = crawler.settings queue = build_from_crawler( ScrapyPriorityQueue, crawler, downstream_queue_cls=load_object(settings["SCHEDULER_MEMORY_QUEUE"]), key="", start_queue_cls=load_object(settings["SCHEDULER_START_MEMORY_QUEUE"]), ) for request in input_requests: queue.push(request) actual_output_urls = [] while request := queue.pop(): actual_output_urls.append(request.url) assert actual_output_urls == expected_output_urls