feat: python serverless api with a self-hosted serverless gateway (#31)

Example of Python Serverless API deployment using Serverless API Framework and a self-hosted Serverless Gateway

Author: redanrd

README.md

@@ -46,7 +46,8 @@ Table of Contents:
 | **[Rust MNIST](functions/rust-mnist/README.md)** <br/> A Rust function to recognize hand-written digits with a simple neural network.              | rust165   | [Serverless Framework] |
 | **[PostgreSQL Python](functions/postgre-sql-python/README.md)** <br/> A Python function to perform a query on a PostgreSQL managed database.       | python310 | [Serverless Framework] |
 | **[Terraform Python](functions/terraform-python-example/README.md)** <br/> A Python function deployed with Terraform.                              | python310 | [Terraform]            |
-| **[Typescript with Node runtime](functions/typescript-with-node/README.md)** <br/> A Typescript function using Node runtime.                       | node18    | [Serverless Framework] |
+| **[Typescript with Node runtime](functions/typescript-with-node/README.md)** <br/> A Typescript function using Node runtime.                       | node18    | [Serverless Framework]            |
+| **[Serverless Gateway Python Example](functions/serverless-gateway-python/README.md)** <br/> A Python serverless API using Serverless Gateway.     | python310    | [Python API Framework]            |
 
 ### 📦 Containers
 
@@ -61,6 +62,7 @@ Table of Contents:
 | Example                                                                                                                                   | Services    | Language | Deployment             |
 |-------------------------------------------------------------------------------------------------------------------------------------------|-------------|----------|------------------------|
 | **[Kong API Gateway](projects/kong-api-gateway/README.md)** <br/> Deploying a Kong Gateway on containers to provide routing to functions. | CaaS & FaaS | Python   | [Serverless Framework] |
+| **[Serverless Gateway](https://github.com/scaleway/serverless-gateway)** <br/> Our serverless gateway for functions and containers.       | API Gateway | Python   | [Python API Framework] |
 | **[Monitoring Glaciers](projects/blogpost-glacier/README.md)** <br/> A project to monitor glaciers and the impact of global warming.      | S3 & RDB    | Golang   | [Serverless Framework] |
 
 [Serverless Framework]: https://github.com/scaleway/serverless-scaleway-functions

functions/serverless-gateway-python/README.md

@@ -0,0 +1,48 @@
+# Using Serverless Gateway and Serverless APIs
+
+This example shows how to serve a Serverless API composed of many functions through our serverless gateway.
+
+## Requirements
+
+This example uses:
+* [Python API Framework](https://github.com/scaleway/serverless-api-project) to deploy the functions.
+* [Serverless Gateway](https://github.com/scaleway/serverless-gateway) to deploy a serverless gateway container.
+
+## Gateway set-up
+
+Deploy the serverless gateway as a container following the Serverless Gateway project instructions.
+
+Make sure to export your gateway base URL (`GATEWAY_HOST`) and an authentication token (`TOKEN`)
+
+## Running 
+
+### Deploy your serverless API
+
+Deploy your functions and add them automatically as endpoints to your serverless gateway using:
+
+```
+pip install -r requirements.txt
+scw-serverless deploy app.py --gateway-url https://${GATEWAY_HOST} --gateway-api-key ${TOKEN}
+```
+
+### Check your endpoint has been added
+
+You can use:
+```
+./list_gateway_endpoints.sh
+```
+
+### Call your function via its route
+
+You can use:
+```
+curl https://${GATEWAY_HOST}/<chosen_relative_path>
+```
+
+### Delete your endpoint
+
+You can use:
+```
+./scripts/delete_function_to_gateway.sh https://<function_domain_name> /<chosen_relative_path>
+```
+

functions/serverless-gateway-python/app.py

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+from  scw_serverless import Serverless
+
+app = Serverless("serverless-api")
+
+@app.get(url="/func-a")
+def func_a(_event, _context):
+    return "Hello from function A"
+
+@app.get(url="/func-b")
+def func_b(_event, _context):
+    return "Hello from function B"
+
+@app.get(url="/func-c")
+def func_c(_event, _context):
+    return "Hello from function C"

functions/serverless-gateway-python/requirements.txt

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+scw-serverless==1.0.1

functions/serverless-gateway-python/scripts/add_function_to_gateway.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+set -e
+
+curl -X POST https://${GATEWAY_URL}/scw \
+             -H 'X-Auth-Token: ${GATEWAY_TOKEN}' \
+             -H 'Content-Type: application/json' \
+             -d '{"target":"$1","relative_url":"$2"}'

functions/serverless-gateway-python/scripts/delete_function_from_gateway.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+set -e
+
+curl -X POST https://${GATEWAY_URL}/scw \
+             -H 'X-Auth-Token: ${GATEWAY_TOKEN}' \
+             -H 'Content-Type: application/json' \
+             -d '{"target":"$1","relative_url":"$2"}'

functions/serverless-gateway-python/scripts/list_gateway_endpoints.sh

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+#!/bin/bash
+set -e
+
+curl https://${GATEWAY_URL}/scw -H 'X-Auth-Token: ${GATEWAY_TOKEN}'