Merge pull request #20 from cloudflare/mikenomitch/adds-vendoring

Adds vendored packages

Author: dom96

06-vendoring/README.md

@@ -0,0 +1,63 @@
+# Vendoring Packages: FastAPI + Jinja2 Example
+
+*Note: You must have Python Packages enabled on your account for built-in packages to work. Request Access to our Closed Beta using [This Form](https://forms.gle/FcjjhV3YtPyjRPaL8)*
+
+This is an example of a Python Worker that uses a built-in package (FastAPI) with a vendored package (Jinja2).
+
+## Adding Packages
+
+Built-in packages can be selected from [this list](https://developers.cloudflare.com/workers/languages/python/packages/#supported-packages) and added to your `requirements.txt` file. These can be used with no other explicit install step.
+
+Vendored packages are added to your source files and need to be installed in a special manner. The Python Workers team plans to make this process automatic in the future, but for now, manual steps need to be taken.
+
+### Vendoring Packages
+
+First, install Python3.12 and pip for Python 3.12.
+
+*Currently, other versions of Python will not work - use 3.12!*
+
+Then create a virtual environment and activate it from your shell:
+```console
+python3.12 -m venv .venv
+source .venv/bin/activate
+```
+
+Within our virtual environment, install the pyodide CLI:
+```console
+.venv/bin/pip install pyodide-build
+.venv/bin/pyodide venv .venv-pyodide
+```
+
+Next, add packages to your vendor.txt file. Here we'll add jinja2
+```
+jinja2
+```
+
+Lastly, add these packages to your source files at `src/vendor`. For any additional packages, re-run this command.
+```console
+.venv-pyodide/bin/pip install -t src/vendor -r vendor.txt
+```
+
+### Using Vendored packages
+
+In your wrangler.toml, make the vendor directory available:
+
+```toml
+[[rules]]
+globs = ["vendor/**"]
+type = "Data"
+fallthrough = true
+```
+
+Now, you can import and use the packages:
+
+```python
+import jinja2
+# ... etc ...
+```
+
+### Developing and Deploying
+
+To develop your Worker, run `wrangler dev`.
+
+To deploy your Worker, run `wrangler deploy`.

06-vendoring/requirements.txt

@@ -0,0 +1 @@
+fastapi

06-vendoring/src/worker.py

@@ -0,0 +1,35 @@
+import jinja2
+from fastapi import FastAPI, Request
+
+environment = jinja2.Environment()
+template = environment.from_string("Hello, {{ name }}!")
+
+
+async def on_fetch(request, env):
+    import asgi
+
+    return await asgi.fetch(app, request, env)
+
+
+app = FastAPI()
+
+
+@app.get("/")
+async def root():
+    message = "This is an example of FastAPI with Jinja2 - go to /hi/<name> to see a template rendered"
+    return {"message": message}
+
+
+@app.get("/hi/{name}")
+async def say_hi(name: str):
+    message = template.render(name=name)
+    return {"message": message}
+
+
+@app.get("/env")
+async def env(req: Request):
+    env = req.scope["env"]
+    return {
+        "message": "Here is an example of getting an environment variable: "
+        + env.MESSAGE
+    }

06-vendoring/vendor.txt

@@ -0,0 +1,2 @@
+markupsafe
+jinja2

06-vendoring/wrangler.toml

@@ -0,0 +1,12 @@
+name = "fastapi-worker"
+main = "src/worker.py"
+compatibility_flags = ["python_workers"]
+compatibility_date = "2025-03-16"
+
+[vars]
+MESSAGE = "My env var"
+
+[[rules]]
+globs = ["vendor/**"]
+type = "Data"
+fallthrough = true

README.md

@@ -20,11 +20,13 @@ Need to deploy your Worker to Cloudflare? Python Workers are in open beta and ha
 - [**`03-fastapi/`**](03-fastapi) — demonstrates how to use the [FastAPI](https://fastapi.tiangolo.com/) package with Python Workers
 - [**`04-langchain/`**](04-langchain) — demonstrates how to use the [LangChain](https://pypi.org/project/langchain/) package with Python Workers
 - [**`05-query-d1/`**](05-query-d1) - shows how to query D1 with Python Workers
+- [**`06-vendoring/`**](06-vendring) - shows how to vendor packages that are not included in the built-in package list
 
 ## Open Beta and Limits
 
-- Python Workers are in open beta. Currently, you can only deploy Python Workers that use the standard library. [Packages](https://developers.cloudflare.com/workers/languages/python/packages/#supported-packages) **cannot be deployed** and will only work in local development for the time being.
-- You must add the `python_workers` compatibility flag to your Worker, while Python Workers are in open beta.
+- Python Workers are in open beta. Currently, you can only deploy Python Workers that use the standard library. [Packages](https://developers.cloudflare.com/workers/languages/python/packages/#supported-packages) **cannot be deployed** and will only work in local development by default.
+- If you wish to join our closed beta which enables deploying packages, fill out [this form](https://forms.gle/827KAtKJTZdgAkNm7).
+- You must add the `python_workers` compatibility flag to your Worker while Python Workers are in open beta.
 
 We’d love your feedback. Join the `#python-workers channel` in the [Cloudflare Developers Discord](https://discord.cloudflare.com/) and let us know what you’d like to see next.