Asyncio

kr8s is built using async/await under the hood when interacting with the Kubernetes API. However, it exposes a standard synchronous API by default.

import kr8s

pods = kr8s.get("pods")

The standard API works by creating a background thread with it’s own event loop running. Then internally the kr8s sync API submits all coroutine calls to this external event loop for execution and then returns the result.

Note

Running a separate event loop allows you to use the sync API even when already inside an async context without blocking up the existing event loop. The most common situation this happens is when using IPython or Jupyter which places your REPL inside a running event loop, but this doesn’t mean everyone wants to do async programming in those environments.

kr8s.asyncio submodule

For users that want to use kr8s with asyncio or trio you can find the async API is directly available via kr8s.asyncio.

import kr8s.asyncio

pods = [pod async for pod in kr8s.asyncio.get("pods")]

Submodules including kr8s.objects and kr8s.portforward also have asyncio equivalents at kr8s.asyncio.objects and kr8s.asyncio.portforward.

Documentation examples

Throughout the kr8s documentation we strive to provide code examples using both the sync and async APIs, you will see tab selectors like this which allows you to easily compare the two APIs and choose the one you wish to use.

Sync

from kr8s.objects import Pod

pod = Pod({
        "apiVersion": "v1",
        "kind": "Pod",
        "metadata": {
            "name": "my-pod",
        },
        "spec": {
            "containers": [{"name": "pause", "image": "gcr.io/google_containers/pause",}]
        },
    })

pod.create()

Async

from kr8s.asyncio.objects import Pod

pod = await Pod({
        "apiVersion": "v1",
        "kind": "Pod",
        "metadata": {
            "name": "my-pod",
        },
        "spec": {
            "containers": [{"name": "pause", "image": "gcr.io/google_containers/pause",}]
        },
    })

await pod.create()