drop dependency on 'urllib3'

.pre-commit-config.yaml

@@ -38,7 +38,6 @@ repos:
           - pytest
           - tornado
           - pyarrow
-          - urllib3
           - git+https://github.com/dask/dask
           - git+https://github.com/dask/zict
 

continuous_integration/environment-mindeps.yaml

@@ -19,7 +19,6 @@ dependencies:
   - tblib=1.6.0
   - toolz=0.12.0
   - tornado=6.2.0
-  - urllib3=1.26.5
   - zict=3.0.0
   # Distributed depends on the latest version of Dask
   - pip

continuous_integration/recipes/distributed/meta.yaml

@@ -41,7 +41,6 @@ requirements:
     - tblib >=1.6.0,!=3.2.0,!=3.2.1
     - toolz >=0.10.0
     - tornado >=6.2.0
-    - urllib3 >=1.26.5
     - zict >=3.0.0
   run_constrained:
     - openssl !=1.1.1e

distributed/preloading.py

@@ -6,6 +6,9 @@
 import os
 import shutil
 import sys
+import time
+import urllib.error
+import urllib.request
 from collections.abc import Iterable, Sequence
 from importlib import import_module
 from types import ModuleType
@@ -129,21 +132,22 @@ def _import_module(name: str, file_dir: str | None = None) -> ModuleType:
 def _download_module(url: str) -> ModuleType:
     logger.info("Downloading preload at %s", url)
     assert is_webaddress(url)
-    # This is the only place where urllib3 is used and it is a relatively heavy
-    # import. Do lazy import to reduce import time
-    import urllib3
-
-    with urllib3.PoolManager() as http:
-        response = http.request(
-            method="GET",
-            url=url,
-            retries=urllib3.util.Retry(
-                status_forcelist=[429, 504, 503, 502],
-                backoff_factor=0.2,
-            ),
-        )
 
-        source = response.data
+    retryable_codes = {429, 502, 503, 504}
+    backoff_factor = 0.2
+    max_retries = 3
+
+    for attempt in range(max_retries + 1):
+        try:
+            with urllib.request.urlopen(url) as response:
+                source = response.read()
+            break
+        except urllib.error.HTTPError as e:
+            if e.code in retryable_codes and attempt < max_retries:
+                retry_delay_seconds = backoff_factor * (2**attempt)
+                time.sleep(retry_delay_seconds)
+                continue
+            raise
 
     compiled = compile(source, url, "exec")
     module = ModuleType(url)

distributed/tests/test_preload.py

@@ -176,13 +176,13 @@ async def test_preload_import_time():
 async def test_web_preload():
     with (
         mock.patch(
-            "urllib3.PoolManager.request",
+            "urllib.request.urlopen",
             **{
-                "return_value.data": b"def dask_setup(dask_server):"
+                "return_value.__enter__.return_value.read.return_value": b"def dask_setup(dask_server):"
                 b"\n    dask_server.foo = 1"
                 b"\n"
             },
-        ) as request,
+        ) as mock_urlopen,
         captured_logger("distributed.preloading") as log,
     ):
         async with Scheduler(
@@ -200,9 +200,7 @@ async def test_web_preload():
             )
             is not None
         )
-    assert request.mock_calls == [
-        mock.call(method="GET", url="http://example.com/preload", retries=mock.ANY)
-    ]
+    assert mock_urlopen.call_args_list == [mock.call("http://example.com/preload")]
 
 
 @gen_cluster(nthreads=[])
@@ -233,15 +231,13 @@ async def test_web_preload_worker():
         dask.config.set(scheduler_address="tcp://127.0.0.1:{port}")
         """).encode()
     with mock.patch(
-        "urllib3.PoolManager.request",
-        **{"return_value.data": data},
-    ) as request:
+        "urllib.request.urlopen",
+        **{"return_value.__enter__.return_value.read.return_value": data},
+    ) as mock_urlopen:
         async with Scheduler(port=port, host="localhost", dashboard_address=":0") as s:
             async with Nanny(preload_nanny=["http://example.com/preload"]) as nanny:
                 assert nanny.scheduler_addr == s.address
-    assert request.mock_calls == [
-        mock.call(method="GET", url="http://example.com/preload", retries=mock.ANY)
-    ]
+    assert mock_urlopen.call_args_list == [mock.call("http://example.com/preload")]
 
 
 # This test is blocked on https://github.com/dask/distributed/issues/5819

pixi.toml

@@ -30,5 +30,4 @@ psutil = ">=5.8.0"
 sortedcontainers = ">=2.0.5"
 tblib = ">=1.6.0,!=3.2.0,!=3.2.1"
 tornado = ">=6.2.0"
-urllib3 = ">=1.26.5"
 zict = ">=3.0.0"

pyproject.toml

@@ -40,7 +40,6 @@ dependencies = [
     "tblib >= 1.6.0,!=3.2.0,!=3.2.1",
     "toolz >= 0.12.0",
     "tornado >= 6.2.0",
-    "urllib3 >= 1.26.5",
     "zict >= 3.0.0",
 ]
 dynamic = ["version"]