awslambda
=========
*A tool for deploying Python projects to AWS Lambda.*
Getting started
---------------
Authentication is left to *boto3* so you can set it up just like the `regular
AWS CLI <http://docs.aws.amazon.com/lambda/latest/dg/setup.html>`_. You need an
`S3 bucket
<http://docs.aws.amazon.com/AmazonS3/latest/gsg/CreatingABucket.html>`_ for
temporary storage. For a quick tutorial on execution roles, see the `official
docs
<http://docs.aws.amazon.com/lambda/latest/dg/with-s3-example-create-iam-role.html>`_
(of course you need one that can execute lambdas).
In a new folder, create *mymodule.py*.
.. code:: python
def hello(*args):
return "Hello, world!"
Then deploy the function (fill in your execution role resource name from the
AWS console).
::
awslambda . mybucket --create hello mymodule.hello arn:aws:iam::xxxxxxxxxxxx:role/myrole
When *awslambda* is done, you can test your new function in the Lambda
management console.
>From now on, if you make changes to the function, just run:
::
awslambda . mybucket --update hello
You can use as many options as you like (some shown here with short names).
::
awslambda . mybucket -u hello -u myotherlambda --delete myoldlambda
Or specify your functions in a YAML file (let's call it *sync.yaml*).
.. code:: yaml
hello:
handler: mymodule.hello
role: arn:aws:iam::xxxxxxxxxxxx:role/myrole
# myotherlambda:
# handler: myothermodule.myotherhandler
# role: arn:aws:iam::xxxxxxxxxxxx:role/myrole
When syncing from a file, *awslambda* will update existing functions and create
the others automatically.
::
awslambda . mybucket --sync sync.yaml
To add dependencies, use your `pip requirements file
<https://pip.readthedocs.io/en/stable/user_guide/#requirements-files>`_.
::
awslambda . mybucket -s sync.yaml --requirements requirements.txt
*Note that compiled dependencies* awslambda *downloads on your local machine
might not work on the AWS servers. Pure Python libraries should always work.
For others, it could be helpful to run* awslambda *itself in a Lambda function.
A process knows as* awslambdaception.
A template greeting page
........................
Let's use the features introduced above to create a greeting page. We will use
the `Jinja2 <http://jinja.pocoo.org>`_ templating engine.
Edit *mymodule.py*,
.. code:: python
from jinja2 import Template
template = Template('''
<html>
<body>
<h1>Hello, {{ parameters.name }}!</h1>
<p>{{ parameters.message }}</p>
</body>
</html>
''')
def hello(event, context):
return {
'statusCode': 200,
'headers': {'Content-Type': 'text/HTML'},
'body': template.render(parameters=event['queryStringParameters'])}
and create a simple *requirements.txt*.
::
Jinja2
Deploy,
::
awslambda . mybucket -s sync.yaml -r requirements.txt
then open the function in your AWS console. Go to *Triggers* and add an
*API Gateway* trigger. Set security to *Open* for now. Open the URL of the
created trigger in your browser. You should see "Hello, !". To customize the
page append e.g.
::
?name=Commander Shepard&message=You've received a new message at your private terminal.
to the URL and enjoy your serverless, templated webpage!
Usage
-----
::
Usage: awslambda [OPTIONS] SOURCE_DIR S3_BUCKET
Deploy Python code to AWS lambda.
Zips the contents of the source directory together with optional pip
requirements. The archive is temporarily uploaded to an S3 bucket and used
to create or update lambda functions.
Reference handlers from your source directory like you would in any Python
module-tree (e.g. mymodule.myhandler, mymodule.mysubmodule.myhandler,
etc.).
Roles are ARNs like "arn:aws:iam::xxxxxxxxxxxx:role/myrole"
YAML file entries for the sync option map function names to handlers and
roles:
myLambda:
handler: mymodule.myhandler
role: arn:aws:iam::xxxxxxxxxxxx:role/myrole
Options:
-r, --requirements PATH pip compatible requirements file. Will be
included in the archive.
-c, --create NAME HANDLER ROLE Create a new lambda function. Example:
--create myLambda mymodule.myhandler myrole
-u, --update NAME Update a lambda function.
-d, --delete NAME Delete a lambda function.
-s, --sync FILENAME Keep lambdas defined in YAML file in sync
with deployed lambdas.
--help Show this message and exit.