=========== AWS Chalice
.. image:: https://img.shields.io/pypi/v/chalice.svg?style=flat :target: https://pypi.python.org/pypi/chalice/ :alt: Package Version
.. image:: https://img.shields.io/pypi/pyversions/chalice.svg?style=flat :target: https://pypi.python.org/pypi/chalice/ :alt: Python Versions
.. image:: https://readthedocs.org/projects/chalice/badge/?version=latest :target: https://aws.github.io/chalice/?badge=latest :alt: Documentation Status
.. image:: https://img.shields.io/pypi/l/chalice.svg?style=flat :target: https://github.com/aws/chalice/blob/master/LICENSE :alt: License
.. image:: https://aws.github.io/chalice/_static/img/chalice-logo-whitespace.png :target: https://aws.github.io/chalice/ :alt: Chalice Logo
Chalice is a framework for writing serverless apps in Python. It allows you to quickly create and deploy applications that use AWS Lambda. It provides:
- A command line tool for creating, deploying, and managing your app
- A decorator based API for integrating with Amazon API Gateway, Amazon S3, Amazon SNS, Amazon SQS, and other AWS services.
- Automatic IAM policy generation
You can create Rest APIs:
.. code-block:: python
from chalice import Chalice
app = Chalice(app_name="helloworld")
@app.route("/")
def index():
return {"hello": "world"}
Tasks that run on a periodic basis:
.. code-block:: python
from chalice import Chalice, Rate
app = Chalice(app_name="helloworld")
# Automatically runs every 5 minutes
@app.schedule(Rate(5, unit=Rate.MINUTES))
def periodic_task(event):
return {"hello": "world"}
You can connect a lambda function to an S3 event:
.. code-block:: python
from chalice import Chalice
app = Chalice(app_name="helloworld")
# Whenever an object is uploaded to "mybucket"
# this lambda function will be invoked.
@app.on_s3_event(bucket="mybucket")
def handler(event):
print(
f"Object uploaded for bucket: {event.bucket}, key: {event.key}"
)
As well as an SQS queue:
.. code-block:: python
from chalice import Chalice
app = Chalice(app_name="helloworld")
# Invoke this lambda function whenever a message
# is sent to the ``my-queue-name`` SQS queue.
@app.on_sqs_message(queue="my-queue-name")
def handler(event):
for record in event:
print(f"Message body: {record.body}")
And several other AWS resources.
Once you've written your code, you just run chalice deploy
and Chalice takes care of deploying your app.
::
$ chalice deploy
...
https://endpoint/api
$ curl https://endpoint/api
{"hello": "world"}
Up and running in less than 30 seconds. Give this project a try and share your feedback with us here on GitHub.
The documentation is available
here __.
Quickstart
.. quick-start-begin
In this tutorial, you'll use the chalice command line utility
to create and deploy a basic REST API. This quickstart uses Python 3.10,
but AWS Chalice supports all versions of Python supported by AWS Lambda,
which includes Python 3.10 through Python 3.14.
To install Chalice, we'll first create and activate a virtual environment in python3.10::
$ python3 --version
Python 3.10.20
$ python3 -m venv .venv
$ . .venv/bin/activate
Next we'll install Chalice using pip::
$ python3 -m pip install chalice
You can verify you have chalice installed by running::
$ chalice --help
Usage: chalice [OPTIONS] COMMAND [ARGS]...
...
Credentials
Before you can deploy an application, be sure you have credentials configured. If you have previously configured your machine to run boto3 (the AWS SDK for Python) or the AWS CLI then you can skip this section.
If this is your first time configuring credentials for AWS you can follow these steps to quickly get started::
$ mkdir ~/.aws
$ cat >> ~/.aws/config
[default]
aws_access_key_id=YOUR_ACCESS_KEY_HERE
aws_secret_access_key=YOUR_SECRET_ACCESS_KEY
region=YOUR_REGION (such as us-west-2, us-west-1, etc)
If you want more information on all the supported methods for
configuring credentials, see the
boto3 docs __.
Creating Your Project
The next thing we'll do is use the chalice command to create a new
project::
$ chalice new-project helloworld
This will create a helloworld directory. Cd into this
directory. You'll see several files have been created for you::
$ cd helloworld
$ ls -la
drwxr-xr-x .chalice
-rw-r--r-- app.py
-rw-r--r-- requirements.txt
You can ignore the .chalice directory for now, the two main files
we'll focus on is app.py and requirements.txt.
Let's take a look at the app.py file:
.. code-block:: python
from chalice import Chalice
app = Chalice(app_name='helloworld')
@app.route('/')
def index():
return {'hello': 'world'}
The new-project command created a sample app that defines a
single view, /, that when called will return the JSON body
{"hello": "world"}.
Deploying
Let's deploy this app. Make sure you're in the helloworld
directory and run chalice deploy::
$ chalice deploy
Creating deployment package.
Creating IAM role: helloworld-dev
Creating lambda function: helloworld-dev
Creating Rest API
Resources deployed:
- Lambda ARN: arn:aws:lambda:us-west-2:123456789012:function:helloworld-dev
- Rest API URL: https://abcd.execute-api.us-west-2.amazonaws.com/api/
You now have an API up and running using API Gateway and Lambda::
$ curl https://abcd.execute-api.us-west-2.amazonaws.com/api/
{"hello": "world"}
Try making a change to the returned dictionary from the index()
function. You can then redeploy your changes by running chalice deploy.
.. quick-start-end
Next Steps
You've now created your first app using chalice. You can make
modifications to your app.py file and rerun chalice deploy to
redeploy your changes.
At this point, there are several next steps you can take.
Tutorials__- Choose from among several guided tutorials that will give you step-by-step examples of various features of Chalice.
Topics__ - Deep dive into documentation on specific areas of Chalice. This contains more detailed documentation than the tutorials.API Reference__ - Low level reference documentation on all the classes and methods that are part of the public API of Chalice.
If you're done experimenting with Chalice and you'd like to cleanup, you can
use the chalice delete command, and Chalice will delete all the resources
it created when running the chalice deploy command.
::
$ chalice delete
Deleting Rest API: abcd4kwyl4
Deleting function arn:aws:lambda:region:123456789012:function:helloworld-dev
Deleting IAM Role helloworld-dev
Feedback
We'd also love to hear from you. Please create any GitHub issues for additional features you'd like to see over at https://github.com/aws/chalice/issues.