feat: add dev command (#83)

* feat: add dev command

* fix: update lockfile

* chore: remove boto3

* chore: revert gateway auth key changes

* chore: update lockfile

* fix: do not store handler in function

* chore: update poetry lock

* fix: missing scaleway-functions-python

* test: increase retry

* docs: add README section

Author: cyclimse

README.md

@@ -59,6 +59,20 @@ def hello_world(event, context):
 The configuration is done by passing arguments to the decorator.
 To view which arguments are supported, head over to this [documentation](https://serverless-api-framework-python.readthedocs.io/) page.
 
+### Local testing
+
+Before deploying, you can run your functions locally with the dev command:
+
+```console
+scw-serverless dev app.py
+```
+
+This runs a local Flask server with your Serverless handlers. If no `relative_url` is defined for a function, it will be served on `/name` with `name` being the name of your Python function.
+
+By default, this runs Flask in debug mode which includes hot-reloading. You can disable this behavior by passing the `--no-debug` flag.
+
+### Deploying
+
 When you are ready, you can deploy your function with the `scw-serverless` CLI tool:
 
 ```console

docs/source/deploying.rst

@@ -1,7 +1,30 @@
 Deploying
 =========
 
-After writing your functions, the included CLI tool `scw-serverless` helps deploy your application on Scaleway.
+After writing your functions, the included CLI tool `scw-serverless` helps test and deploy your application on Scaleway.
+
+Running locally
+---------------
+
+You can test your functions locally before deploying with the `dev` command:
+
+.. code-block:: console
+
+    scw-serverless dev app.py
+
+This will start a local Flask server with your functions that will behave similarly to Scaleway Functions.
+
+By default, functions are served by `/name` on port 8080 with the name being the name of the Python function.
+
+You can then use your favorite tools to query the functions:
+
+.. code-block:: console
+
+    # For a function named def handle()...
+    curl http://localhost:8080/handle
+
+This command allows you to test your code, but as this test environment is not quite the same as Scaleway Functions,
+there might be slight differences when deploying.
 
 Deploy
 ------

examples/hello_world/handler.py

@@ -13,4 +13,4 @@ def handle(_event: dict[str, Any], _content: dict[str, Any]) -> dict[str, Any]:
         context (dict): function call metadata
     """
 
-    return {"message": "Hello from Scaleway functions using Serverless API Framework"}
+    return {"body": "Hello from Scaleway functions using Serverless API Framework"}

poetry.lock

@@ -33,9 +33,10 @@ include = ["CHANGELOG.md"]
 scw-serverless = "scw_serverless.cli:cli"
 
 [tool.poetry.dependencies]
-python = "^3.9"
+python = ">=3.9,<3.12"
 click = "^8.1.3"
 scaleway = ">=0.7,<0.13"
+scaleway-functions-python = "^0.2.0"
 requests = "^2.28.2"
 typing-extensions = { version = "^4.4.0", python = "<3.11" }
 

pyproject.toml

@@ -5,7 +5,8 @@
 import click
 from scaleway import ScalewayException
 
-from scw_serverless import deployment, loader, logger
+import scw_serverless
+from scw_serverless import app, deployment, loader, local_app, logger
 from scw_serverless.dependencies_manager import DependenciesManager
 from scw_serverless.gateway.gateway_manager import GatewayManager
 
@@ -145,3 +146,30 @@ def deploy(
             sdk_client=client,
         )
         manager.update_routes()
+
+
+@cli.command()
+@CLICK_ARG_FILE
+@click.option(
+    "--port",
+    "-p",
+    "port",
+    default=8080,
+    show_default=True,
+    help="Set port to listen on.",
+)
+@click.option(
+    "--debug/--no-debug",
+    "debug",
+    default=True,
+    show_default=True,
+    help="Run Flask in debug mode.",
+)
+def dev(file: Path, port: int, debug: bool) -> None:
+    """Run functions locally with Serverless Local Testing."""
+    app.Serverless = local_app.ServerlessLocal
+    scw_serverless.Serverless = local_app.ServerlessLocal
+    app_instance = cast(
+        local_app.ServerlessLocal, loader.load_app_instance(file.resolve())
+    )
+    app_instance.local_server.serve(port=port, debug=debug)

scw_serverless/cli.py

@@ -57,7 +57,7 @@ class Function:
     """Representation of a Scaleway function."""
 
     name: str
-    handler: str  # Path to the handler
+    handler_path: str
     environment_variables: Optional[dict[str, str]] = None
     min_scale: Optional[int] = None
     max_scale: Optional[int] = None
@@ -85,7 +85,7 @@ def from_handler(
             gateway_route = GatewayRoute(url, http_methods=args.get("http_methods"))
         return Function(
             name=to_valid_function_name(handler.__name__),
-            handler=module_to_path(handler.__module__) + "." + handler.__name__,
+            handler_path=module_to_path(handler.__module__) + "." + handler.__name__,
             environment_variables=args.get("env"),
             min_scale=args.get("min_scale"),
             max_scale=args.get("max_scale"),

scw_serverless/config/function.py

@@ -89,7 +89,7 @@ def create_function(
             max_scale=function.max_scale,
             memory_limit=function.memory_limit,
             timeout=function.timeout,
-            handler=function.handler,
+            handler=function.handler_path,
             description=function.description,
             secret_environment_variables=self._get_secrets_from_dict(
                 function.secret_environment_variables
@@ -110,7 +110,7 @@ def update_function(
             max_scale=function.max_scale,
             memory_limit=function.memory_limit,
             timeout=function.timeout,
-            handler=function.handler,
+            handler=function.handler_path,
             description=function.description,
             secret_environment_variables=self._get_secrets_from_dict(
                 function.secret_environment_variables