Add tenacity for polling (#260)

* Add tenacity for polling

natural4-server/natural4_server/hello.py

@@ -229,7 +229,8 @@ async def petri_post_process(target_folder):
     # stem is respectively a timestamp 2025-01-06T03:00:52
     timestamp = (await dot_path.readlink()).stem
 
-    flowchart_tasks: asyncio.Task[None] = cyz.pipe(get_flowchart_tasks(target_folder, timestamp), run_tasks)
+    flowchart_tasks: asyncio.Task[None] = cyz.pipe(
+        get_flowchart_tasks(target_folder, timestamp), run_tasks)
 
     return timestamp, flowchart_tasks
 

natural4-server/pyproject.toml

@@ -37,6 +37,7 @@ dev-dependencies = [
     "pre-commit<4.0.0,>=3.6.2",
     "coverage<8.0.0,>=7.4.3",
     "pytest-asyncio>=0.24.0",
+    "tenacity>=9.0.0",
 ]
 
 [tool.ruff]

natural4-server/tests/test_endpoint.py

@@ -1,8 +1,20 @@
-from time import sleep, time
+from time import sleep
 
 from sanic import Sanic
 from sanic.application.constants import ServerStage
 from sanic_testing.reusable import ReusableClient
+from tenacity import retry, retry_if_result, stop_after_delay, wait_fixed
+
+
+def is_not_200(value):
+    """Return True if value is None"""
+    return value != 200
+
+@retry(retry=(retry_if_result(is_not_200)), wait=wait_fixed(5), stop=stop_after_delay(30))
+def poll_url(client, url):
+    print(f"Waiting for {url}...")
+    request, response = client.get(url)
+    return response.status
 
 
 def test_post(app: Sanic, post_data):
@@ -32,22 +44,9 @@ def test_post(app: Sanic, post_data):
             request, response_json = client.get(f"{workdir_url}/petri/LATEST-small.png")
             assert response_json.status == 200
 
-            start_time = time()
-            while time() - start_time < 60:
-                print("Waiting for PDF...")
-                request, response_pdf = client.get(f"{workdir_url}/docx/LATEST.docx")
-                if response_pdf.status != 200:
-                    sleep(5)
-                else:
-                    break
-
-            start_time = time()
-            while time() - start_time < 60:
-                print("Waiting for PDF...")
-                request, response_pdf = client.get(f"{workdir_url}/pdf/LATEST.pdf")
-                if response_pdf.status != 200:
-                    sleep(5)
-                else:
-                    break
-
-            assert response_pdf.status == 200
+            response_docx = poll_url(client, f"{workdir_url}/docx/LATEST.docx")
+            assert response_docx == 200
+
+            response_pdf = poll_url(client, f"{workdir_url}/pdf/LATEST.pdf")
+
+            assert response_pdf == 200