list crawler implementation (#5123)

moto/glue/models.py

@@ -24,6 +24,12 @@ from ..utilities.paginator import paginate
 
 class GlueBackend(BaseBackend):
     PAGINATION_MODEL = {
+        "list_crawlers": {
+            "input_token": "next_token",
+            "limit_key": "max_results",
+            "limit_default": 100,
+            "unique_attribute": "name",
+        },
         "list_jobs": {
             "input_token": "next_token",
             "limit_key": "max_results",
@@ -143,6 +149,10 @@ class GlueBackend(BaseBackend):
     def get_crawlers(self):
         return [self.crawlers[key] for key in self.crawlers] if self.crawlers else []
 
+    @paginate(pagination_model=PAGINATION_MODEL)
+    def list_crawlers(self):
+        return [crawler for _, crawler in self.crawlers.items()]
+
     def start_crawler(self, name):
         crawler = self.get_crawler(name)
         crawler.start_crawler()
@@ -380,6 +390,9 @@ class FakeCrawler(BaseModel):
         self.crawl_elapsed_time = 0
         self.last_crawl_info = None
 
+    def get_name(self):
+        return self.name
+
     def as_dict(self):
         last_crawl = self.last_crawl_info.as_dict() if self.last_crawl_info else None
         data = {

moto/glue/responses.py

@@ -307,6 +307,30 @@ class GlueResponse(BaseResponse):
         crawlers = self.glue_backend.get_crawlers()
         return json.dumps({"Crawlers": [crawler.as_dict() for crawler in crawlers]})
 
+    def list_crawlers(self):
+        next_token = self._get_param("NextToken")
+        max_results = self._get_int_param("MaxResults")
+        tags = self._get_param("Tags")
+        crawlers, next_token = self.glue_backend.list_crawlers(
+            next_token=next_token, max_results=max_results
+        )
+        filtered_crawler_names = self.filter_crawlers_by_tags(crawlers, tags)
+        return json.dumps(
+            dict(
+                CrawlerNames=[crawler_name for crawler_name in filtered_crawler_names],
+                NextToken=next_token,
+            )
+        )
+
+    def filter_crawlers_by_tags(self, crawlers, tags):
+        if not tags:
+            return [crawler.get_name() for crawler in crawlers]
+        return [
+            crawler.get_name()
+            for crawler in crawlers
+            if self.is_tags_match(crawler.tags, tags)
+        ]
+
     def start_crawler(self):
         name = self.parameters.get("Name")
         self.glue_backend.start_crawler(name)
@@ -402,9 +426,9 @@ class GlueResponse(BaseResponse):
         return [job.get_name() for job in jobs if self.is_tags_match(job.tags, tags)]
 
     @staticmethod
-    def is_tags_match(job_tags, tags):
+    def is_tags_match(glue_resource_tags, tags):
-        mutual_keys = set(job_tags).intersection(tags)
+        mutual_keys = set(glue_resource_tags).intersection(tags)
         for key in mutual_keys:
-            if job_tags[key] == tags[key]:
+            if glue_resource_tags[key] == tags[key]:
                 return True
         return False

tests/test_glue/test_glue.py

@@ -193,7 +193,7 @@ def test_list_jobs_with_tags():
 
 
 @mock_glue
-def test_next_token_logic_does_not_create_infinite_loop():
+def test_list_jobs_next_token_logic_does_not_create_infinite_loop():
     client = create_glue_client()
     create_test_jobs(client, 4)
     first_response = client.list_jobs(MaxResults=1)
@@ -228,3 +228,66 @@ def create_test_job_w_all_attributes(client, **job_attributes):
 def create_test_jobs(client, number_of_jobs):
     for _ in range(number_of_jobs):
         create_test_job(client)
+
+
+def create_test_crawler(client, tags=None):
+    crawler_name = str(uuid4())
+    client.create_crawler(
+        Name=crawler_name,
+        Role="test_role",
+        Targets={"S3Targets": [{"Path": "s3://tests3target"}]},
+        Tags=tags or {},
+    )
+    return crawler_name
+
+
+def create_test_crawlers(client, number_of_crawlers):
+    for _ in range(number_of_crawlers):
+        create_test_crawler(client)
+
+
+@mock_glue
+def test_list_crawlers_with_max_results():
+    client = create_glue_client()
+    create_test_crawlers(client, 4)
+    response = client.list_crawlers(MaxResults=2)
+    response["CrawlerNames"].should.have.length_of(2)
+    response.should.have.key("NextToken")
+
+
+@mock_glue
+def test_list_crawlers_from_next_token():
+    client = create_glue_client()
+    create_test_crawlers(client, 10)
+    first_response = client.list_crawlers(MaxResults=3)
+    response = client.list_crawlers(NextToken=first_response["NextToken"])
+    response["CrawlerNames"].should.have.length_of(7)
+
+
+@mock_glue
+def test_list_crawlers_with_max_results_greater_than_actual_results():
+    client = create_glue_client()
+    create_test_crawlers(client, 4)
+    response = client.list_crawlers(MaxResults=10)
+    response["CrawlerNames"].should.have.length_of(4)
+
+
+@mock_glue
+def test_list_crawlers_with_tags():
+    client = create_glue_client()
+    create_test_crawler(client)
+    create_test_crawler(client, {"string": "string"})
+    response = client.list_crawlers(Tags={"string": "string"})
+    response["CrawlerNames"].should.have.length_of(1)
+
+
+@mock_glue
+def test_list_crawlers_next_token_logic_does_not_create_infinite_loop():
+    client = create_glue_client()
+    create_test_crawlers(client, 4)
+    first_response = client.list_crawlers(MaxResults=1)
+    next_token = first_response["NextToken"]
+    while next_token:
+        response = client.list_crawlers(NextToken=next_token)
+        next_token = response.get("NextToken")
+    assert not next_token