cloudflare · hoodmane · Jun 12, 2026 · May 2, 2026 · May 2, 2026
diff --git a/16-sync-http-clients/README.md b/16-sync-http-clients/README.md
@@ -0,0 +1,45 @@
+# Sync HTTP Clients Example
+
+This example demonstrates outbound HTTP from a Python Worker using synchronous Python HTTP clients known to work in the current runtime:
+
+- [`requests`](https://pypi.org/project/requests/)
+- [`urllib3`](https://pypi.org/project/urllib3/)
+- [`httpx.Client`](https://www.python-httpx.org/)
+
+It intentionally calls their normal blocking-style APIs from inside the Worker handler.
+
+## How to Run
+
+First ensure that `uv` is installed:
+https://docs.astral.sh/uv/getting-started/installation/#standalone-installer
+
+Run:
+
+```sh
+uv run pywrangler dev
+```
+
+Then try:
+
+```sh
+curl http://localhost:8787/
+curl http://localhost:8787/sync
+```
+
+You can also deploy with:
+
+```sh
+uv run pywrangler deploy
+```
+
+## Endpoints
+
+| Endpoint | Description |
+|---|---|
+| `GET /` | Endpoint index |
+| `GET /sync` | Fetch with `requests.get()`, `urllib3.PoolManager().request()`, and `httpx.Client` |
+| `GET /all` | Alias for `/sync` |
+
+## Notes
+
+This example is limited to synchronous package-backed clients that work in Python Workers. It does not include stdlib raw-socket clients such as `urllib.request` or `http.client`.
diff --git a/16-sync-http-clients/package.json b/16-sync-http-clients/package.json
@@ -0,0 +1,13 @@
+{
+	"name": "python-sync-http-clients",
+	"version": "0.0.0",
+	"private": true,
+	"scripts": {
+		"deploy": "uv run pywrangler deploy",
+		"dev": "uv run pywrangler dev",
+		"start": "uv run pywrangler dev"
+	},
+	"devDependencies": {
+		"wrangler": "^4.46.0"
+	}
+}
diff --git a/16-sync-http-clients/pyproject.toml b/16-sync-http-clients/pyproject.toml
@@ -0,0 +1,18 @@
+[project]
+name = "python-sync-http-clients"
+version = "0.1.0"
+description = "Synchronous HTTP clients in Python Workers"
+readme = "README.md"
+requires-python = ">=3.12"
+dependencies = [
+    "httpx>=0.28.0",
+    "requests>=2.32.0",
+    "urllib3>=2.5.0",
+    "workers-runtime-sdk>=1.1.1",
+]
+
+[dependency-groups]
+dev = [
+    "workers-py",
+    "workers-runtime-sdk"
+]
diff --git a/16-sync-http-clients/src/entry.py b/16-sync-http-clients/src/entry.py
@@ -0,0 +1,76 @@
+import httpx
+import requests
+import urllib3
+from workers import Response, WorkerEntrypoint
+
+TARGET_URL = "https://example.com/"
+EXPECTED_TEXT = "Example Domain"
+
+
+def summarize_result(client, status_code, text, headers=None):
+    """Return a small JSON-safe summary for an outbound HTTP response."""
+    headers = headers or {}
+    return {
+        "client": client,
+        "status_code": int(status_code),
+        "ok": 200 <= int(status_code) < 300,
+        "saw_expected_text": EXPECTED_TEXT in text,
+        "content_type": headers.get("content-type") or headers.get("Content-Type"),
+        "body_preview": text[:80],
+    }
+
+
+class Default(WorkerEntrypoint):
+    async def fetch(self, request):
+        path = request.url.split("/", 3)[-1]
+        path = "/" + path.split("?", 1)[0] if path else "/"
+
+        if path == "/":
+            return Response.json(
+                {
+                    "example": "Synchronous HTTP clients in Python Workers",
+                    "target": TARGET_URL,
+                    "clients": ["requests", "urllib3", "httpx.Client"],
+                    "endpoints": {
+                        "GET /sync": "Fetch using requests, urllib3, and httpx.Client",
+                        "GET /all": "Alias for /sync",
+                    },
+                }
+            )
+
+        if path in ("/sync", "/all"):
+            return Response.json({"target": TARGET_URL, "results": self.fetch_sync()})
+
+        return Response.json({"error": "not found"}, status=404)
+
+    def fetch_sync(self):
+        """Use blocking-style Python HTTP clients from a Python Worker."""
+        requests_response = requests.get(TARGET_URL, timeout=10)
+
+        pool = urllib3.PoolManager()
+        urllib3_response = pool.request("GET", TARGET_URL, timeout=10.0)
+        urllib3_text = urllib3_response.data.decode("utf-8")
+
+        with httpx.Client() as client:
+            httpx_response = client.get(TARGET_URL, timeout=10.0)
+
+        return [
+            summarize_result(
+                "requests",
+                requests_response.status_code,
+                requests_response.text,
+                requests_response.headers,
+            ),
+            summarize_result(
+                "urllib3",
+                urllib3_response.status,
+                urllib3_text,
+                urllib3_response.headers,
+            ),
+            summarize_result(
+                "httpx.Client",
+                httpx_response.status_code,
+                httpx_response.text,
+                httpx_response.headers,
+            ),
+        ]
diff --git a/16-sync-http-clients/wrangler.jsonc b/16-sync-http-clients/wrangler.jsonc
@@ -0,0 +1,12 @@
+{
+	"$schema": "node_modules/wrangler/config-schema.json",
+	"name": "python-sync-http-clients",
+	"main": "src/entry.py",
+	"compatibility_date": "2025-11-02",
+	"compatibility_flags": [
+		"python_workers"
+	],
+	"observability": {
+		"enabled": true
+	}
+}
diff --git a/README.md b/README.md
@@ -30,6 +30,7 @@ Need to deploy your Worker to Cloudflare? Python Workers are in open beta and ha
 - [**`13-js-api-pygments/`**](13-js-api-pygments) — shows how to use [Pygments](https://pygments.org/) to highlight code with Python Workers.
 - [**`14-websocket-stream-consumer/`**](14-websocket-stream-consumer) — shows how to use [WebSocket](https://developers.cloudflare.com/workers/runtime-apis/websockets/) to consume a stream of data with Python Workers.
 - [**`15-chatroom/`**](15-chatroom) - A real-time chatroom using WebSocket.
+- [**`16-sync-http-clients/`**](16-sync-http-clients) — demonstrates outbound HTTP with synchronous Python clients (`requests`, `urllib3`, and `httpx.Client`).
 
 
 

diff --git a/tests/test_examples.py b/tests/test_examples.py
@@ -110,6 +110,24 @@ def test_07_durable_objects(dev_server):
     assert response.text == "No messages"
 
 
+def test_16_sync_http_clients(dev_server):
+    port = dev_server
+    response = requests.get(f"http://localhost:{port}/sync")
+    assert response.status_code == 200
+
+    results = response.json()["results"]
+    assert [result["client"] for result in results] == [
+        "requests",
+        "urllib3",
+        "httpx.Client",
+    ]
+
+    for result in results:
+        assert result["status_code"] == 200
+        assert result["ok"] is True
+        assert result["saw_expected_text"] is True
+
+
 def test_08_cron(dev_server):
     port = dev_server
     response = requests.get(f"http://localhost:{port}")