Skip to content

cloudevents/sdk-python

Repository files navigation

Python SDK for CloudEvents

PyPI version

Status

This SDK is still considered a work in progress, therefore things might (and will) break with every update.

This SDK current supports the following versions of CloudEvents:

  • v1.0
  • v0.3

Python SDK

Package cloudevents provides primitives to work with CloudEvents specification: https://github.com/cloudevents/spec.

Installing

The CloudEvents SDK can be installed with pip:

pip install cloudevents 

Sending CloudEvents

Below we will provide samples on how to send cloudevents using the popular requests library.

Binary HTTP CloudEvent

fromcloudevents.httpimportCloudEventfromcloudevents.conversionimportto_binaryimportrequests# Create a CloudEvent# - The CloudEvent "id" is generated if omitted. "specversion" defaults to "1.0".attributes={"type": "com.example.sampletype1", "source": "https://example.com/event-producer", } data={"message": "Hello World!"} event=CloudEvent(attributes, data) # Creates the HTTP request representation of the CloudEvent in binary content modeheaders, body=to_binary(event) # POSTrequests.post("<some-url>", data=body, headers=headers)

Structured HTTP CloudEvent

fromcloudevents.conversionimportto_structuredfromcloudevents.httpimportCloudEventimportrequests# Create a CloudEvent# - The CloudEvent "id" is generated if omitted. "specversion" defaults to "1.0".attributes={"type": "com.example.sampletype2", "source": "https://example.com/event-producer", } data={"message": "Hello World!"} event=CloudEvent(attributes, data) # Creates the HTTP request representation of the CloudEvent in structured content modeheaders, body=to_structured(event) # POSTrequests.post("<some-url>", data=body, headers=headers)

You can find a complete example of turning a CloudEvent into a HTTP request in the samples' directory.

Receiving CloudEvents

The code below shows how to consume a cloudevent using the popular python web framework flask:

fromflaskimportFlask, requestfromcloudevents.httpimportfrom_httpapp=Flask(__name__) # create an endpoint at http://localhost:/3000/@app.route("/", methods=["POST"])defhome(): # create a CloudEventevent=from_http(request.headers, request.get_data()) # you can access cloudevent fields as seen belowprint( f"Found {event['id']} from {event['source']} with type "f"{event['type']} and specversion {event['specversion']}" ) return"", 204if__name__=="__main__": app.run(port=3000)

You can find a complete example of turning a CloudEvent into a HTTP request in the samples' directory.

SDK versioning

The goal of this package is to provide support for all released versions of CloudEvents, ideally while maintaining the same API. It will use semantic versioning with following rules:

  • MAJOR version increments when backwards incompatible changes is introduced.
  • MINOR version increments when backwards compatible feature is introduced INCLUDING support for new CloudEvents version.
  • PATCH version increments when a backwards compatible bug fix is introduced.

Community

Each SDK may have its own unique processes, tooling and guidelines, common governance related material can be found in the CloudEvents docs directory. In particular, in there you will find information concerning how SDK projects are managed, guidelines for how PR reviews and approval, and our Code of Conduct information.

If there is a security concern with one of the CloudEvents specifications, or with one of the project's SDKs, please send an email to [email protected].

Additional SDK Resources

Maintenance

We use black and isort for autoformatting. We set up a tox environment to reformat the codebase.

e.g.

pip install tox tox -e reformat

For information on releasing version bumps see RELEASING.md